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Biorthogonal-only Floquet Dynamical Quantum Phase Transitions
Authors:
Jiangrong Wen,
Qidong Yuan,
Zi-Xiang Hu,
Jian-Jun Dong
Abstract:
Non-Hermitian dynamical quantum phase transitions (DQPTs) are intrinsically sensitive to the choice of inner product under nonunitary time evolution. Although the biorthogonal formulation based on associated states provides a normalized Loschmidt echo with a probabilistic interpretation, previous studies have found biorthogonal and self-normal DQPTs to occur in the same parameter regimes, suggesti…
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Non-Hermitian dynamical quantum phase transitions (DQPTs) are intrinsically sensitive to the choice of inner product under nonunitary time evolution. Although the biorthogonal formulation based on associated states provides a normalized Loschmidt echo with a probabilistic interpretation, previous studies have found biorthogonal and self-normal DQPTs to occur in the same parameter regimes, suggesting that the two forms of dynamical criticality are concomitant. Here we demonstrate that this is not the case. In an exactly solvable periodically driven non-Hermitian Su-Schrieffer-Heeger chain, we uncover a finite biorthogonal-only Floquet DQPT regime, where the biorthogonal Loschmidt rate becomes nonanalytic while the self-normal Loschmidt rate remains smooth. The critical conditions are obtained analytically, showing that the onset of biorthogonal Floquet DQPTs is locked to the exceptional lines of the effective Floquet Hamiltonian, whereas self-normal criticality has no corresponding spectral boundary. Moreover, for each critical momentum, the biorthogonal DQPT exhibits a pair of critical times within every driving period, whereas the self-normal DQPT exhibits only one. Our results establish a fundamental distinction between biorthogonal and self-normal DQPTs, thereby opening a route toward new nonequilibrium quantum phenomena in non-Hermitian systems.
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Submitted 7 August, 2026;
originally announced August 2026.
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Spectrum-Generating Algebra in Higher Dimensional Gauge Theories
Authors:
Thea Budde,
Jiangjing Dong,
Marina Krstić Marinković,
Joao C. Pinto Barros
Abstract:
Non-equilibrium properties of strongly interacting gauge theories are often intractable with classical simulation methods. Due to recent developments of quantum simulations, studies of their properties in two spatial dimensions are becoming accessible. By demonstrating the existence of an approximate spectrum-generating algebra for a pure gauge plaquette ladder, we predict and verify the existence…
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Non-equilibrium properties of strongly interacting gauge theories are often intractable with classical simulation methods. Due to recent developments of quantum simulations, studies of their properties in two spatial dimensions are becoming accessible. By demonstrating the existence of an approximate spectrum-generating algebra for a pure gauge plaquette ladder, we predict and verify the existence of Quantum Many-Body Scars in spin-1 Quantum Link Models. The analysis of the model is facilitated by a dualization process that maps the original gauge theory to a constrained spin chain. Was it not for the constraint, the system would have an exact spectrum-generating algebra. We propose a set of observables for diagnosing an approximate spectrum-generating algebra, which is expected to guide quantum simulators toward interesting physical regimes.
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Submitted 7 April, 2026;
originally announced April 2026.
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Arbitrarily Configurable Wavefunctions via Imaginary Gauge Phase Imprint in Non-Hermitian Lattices
Authors:
Ji-Long Dong,
Shi-Liang Zhu,
Dan-Wei Zhang
Abstract:
We propose a general framework, termed the imaginary gauge phase imprint (IGPI), which enables engineering arbitrarily configurable wavefunctions with exact solutions and self-organization dynamics in any-dimensional non-Hermitian lattices under imaginary gauge fields. Using this method, we uncover a novel phase with exact critical wavefunctions, dubbed the skin critical phase (SCP), which is mark…
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We propose a general framework, termed the imaginary gauge phase imprint (IGPI), which enables engineering arbitrarily configurable wavefunctions with exact solutions and self-organization dynamics in any-dimensional non-Hermitian lattices under imaginary gauge fields. Using this method, we uncover a novel phase with exact critical wavefunctions, dubbed the skin critical phase (SCP), which is marked by unconventional localization, topological-skin, and dynamical characteristics. Furthermore, we validate the IGPI by imprinting and visualizing complex fractal states with Sierpinski-carpet and Koch-snowflake profiles, as well as exotic super-moire and 3D-moire states in regular lattices. Our work not only offers fresh insights into non-Hermitian critical and fractal physics, but also provides a rigorous paradigm for controlling and visualizing wavefunction patterns using the IGPI in engineered non-Hermitian systems.
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Submitted 15 June, 2026; v1 submitted 30 March, 2026;
originally announced March 2026.
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Quantum Biology, Quantum Simulation and Quantum Coherent Devices
Authors:
Rong-Hang Chen,
Jing Dong,
Wen Yang,
Qing Ai,
Gui-Lu Long
Abstract:
Many living organisms can exploit quantum mechanical effects to gain distinct biological advantages. In plants, photosynthesis uses quantum coherence to achieve near 100% efficiency in energy transfer. With advances in experimental techniques, two-dimensional electronic spectroscopy can reveal dynamic processes such as coherence and coupling within a system, and it plays an important role in study…
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Many living organisms can exploit quantum mechanical effects to gain distinct biological advantages. In plants, photosynthesis uses quantum coherence to achieve near 100% efficiency in energy transfer. With advances in experimental techniques, two-dimensional electronic spectroscopy can reveal dynamic processes such as coherence and coupling within a system, and it plays an important role in studying energy transfer in photosynthesis. On the theory side, methods such as the generalized Bloch-Redfield theory and the hierarchical equations of motion are used to model photosynthetic systems. Quantum simulation, as a high-efficiency and low-complexity approach, has also made progress across various platforms in the study of photosynthesis. In recent years, a series of studies has introduced quantum coherence into artificial systems to enhance energy transfer efficiency, laying the groundwork for the design of coherent devices with efficient energy transport. Birds can use the weak geomagnetic field and spin-dependent chemical reactions to detect direction. Theoretical frameworks for animal navigation include magnetite-based mechanisms, magnetoreceptor genes, and the radical-pair mechanism. Quantum simulations of navigation have also advanced on multiple platforms. Inspired by animal navigation, diverse quantum effects have been applied to improve sensing and to support navigation tasks. This paper presents a comprehensive review of progress on quantum coherence in photosynthesis and avian navigation, along with related theoretical methods, quantum simulation approaches, and research on quantum coherent devices.
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Submitted 18 November, 2025;
originally announced November 2025.
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MiqroForge: An Intelligent Workflow Platform for Quantum-Enhanced Computational Chemistry
Authors:
Jianan Wang,
Wenbo Guo,
Xin Yue,
Minjie Xu,
Yueqiang Zheng,
Jingxiang Dong,
Jiarui Hu,
Jian Xia,
Chuixiong Wu
Abstract:
The connect-fill-run workflow paradigm, widely adopted in mature software engineering, accelerates collaborative development. However, computational chemistry, computational materials science, and computational biology face persistent demands for multi-scale simulations constrained by simplistic platform designs. We present MiqroForge, an intelligent cross-scale platform integrating quantum comput…
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The connect-fill-run workflow paradigm, widely adopted in mature software engineering, accelerates collaborative development. However, computational chemistry, computational materials science, and computational biology face persistent demands for multi-scale simulations constrained by simplistic platform designs. We present MiqroForge, an intelligent cross-scale platform integrating quantum computing capabilities. By combining AI-driven dynamic resource scheduling with an intuitive visual interface, MiqroForge significantly lowers entry barriers while optimizing computational efficiency. The platform fosters a collaborative ecosystem through shared node libraries and data repositories, thereby bridging practitioners across classical and quantum computational domains.
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Submitted 10 August, 2025;
originally announced August 2025.
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Higher-order exceptional lines in a non-Hermitian JaynesCummings triangle
Authors:
Hao Chen,
Xiao Qin,
Jian-Jun Dong,
Yu-Yu Zhang,
Zi-Xiang Hu
Abstract:
Higher-order exceptional points (EPs) in non-Hermitian systems showcase diverse physical phenomena but require more parameter space freedom or symmetries. It leads to a challenge for the exploration of high-order EP geometries in low-dimensional systems. Here we observe both a third-order exceptional surface and line in a Jaynes-Cummings triangle consisting of three cavities arranged in a ring. A…
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Higher-order exceptional points (EPs) in non-Hermitian systems showcase diverse physical phenomena but require more parameter space freedom or symmetries. It leads to a challenge for the exploration of high-order EP geometries in low-dimensional systems. Here we observe both a third-order exceptional surface and line in a Jaynes-Cummings triangle consisting of three cavities arranged in a ring. A fine-tuning artificial magnetic field dramatically enriches the emergence of the third-order exceptional lines ($3$ELs), which require only three tuning parameters in the presence of chiral symmetry and parity-time (PT) symmetry. Third-order EPs amplify the effect of perturbations through a cube-root response mechanism, displaying a greater sensitivity than second-order EPs. We develop novel fidelity and Loschmidt echo using the associated-state biorthogonal approach, which successfully characterizes EPs and quench dynamics even in PT breaking regime. Our work advances the use of higher-order EPs in quantum technology applications.
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Submitted 12 May, 2025;
originally announced May 2025.
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Non-magnetic Fractional Conductance in High Mobility InAs Quantum Point Contacts
Authors:
I. Villar Rodriguez,
Y. Gul,
C. P. Dempsey,
J. T. Dong,
S. N. Holmes,
C. J. Palmstrom,
M. Pepper
Abstract:
In this letter, we report the magneto-electronic properties of high mobility InAs quantum point contacts grown on InP substrates. The 1D conductance reaches a maximum value of 17 plateaus, quantized in units of 2e^2/h, where e is the fundamental unit of charge and h is Planck's constant. The in-plane effective g-factor was estimated to be -10.9 +/- 1.5 for subband N = 1 and -10.8 +/- 1.6 for subba…
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In this letter, we report the magneto-electronic properties of high mobility InAs quantum point contacts grown on InP substrates. The 1D conductance reaches a maximum value of 17 plateaus, quantized in units of 2e^2/h, where e is the fundamental unit of charge and h is Planck's constant. The in-plane effective g-factor was estimated to be -10.9 +/- 1.5 for subband N = 1 and -10.8 +/- 1.6 for subband N = 2. Furthermore, a study of the non-magnetic fractional conductance states at 0.2 (e^2/h) and 0.1(e2/h is provided. While their origin remains under discussion, evidence suggests that they arise from strong electron-electron interactions and momentum-conserving backscattering between electrons in two distinct channels within the 1D region. This phenomenon may also be interpreted as an entanglement between the two channel directions facilitated by momentum-conserving backscattering.
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Submitted 11 March, 2025;
originally announced March 2025.
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Searching Axion-like Dark Matter by Amplifying Weak Magnetic Field with Quantum Zeno effect
Authors:
J. Dong,
W. T. He,
S. D. Zou,
D. L. Zhou,
Q. Ai
Abstract:
The enhancement of weak signals and the detection of hypothetical particles, facilitated by quantum amplification, are crucial for advancing fundamental physics and its practical applications. Recently, it was experimentally observed that magnetic field can be amplified by using nuclear spins under Markovian noise, [H. Su, et al., Phys. Rev. Lett. 133, 191801 (2024)]. Here, we theoretically propos…
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The enhancement of weak signals and the detection of hypothetical particles, facilitated by quantum amplification, are crucial for advancing fundamental physics and its practical applications. Recently, it was experimentally observed that magnetic field can be amplified by using nuclear spins under Markovian noise, [H. Su, et al., Phys. Rev. Lett. 133, 191801 (2024)]. Here, we theoretically propose amplifying the magnetic-field signal by using nuclear spins by the quantum Zeno effect (QZE). Under identical conditions, we demonstrate that compared to the Markovian case the amplification of the weak magnetic field can be enhanced by a factor about $e^{1/2}$ under a Gaussian noise. Moreover, through numerical simulations we determine the optimal experimental parameters for amplification conditions. This work shows that the combination of the QZE and spin amplification effectively enhances the amplification of the weak magnetic field. Our findings may provide valuable guidance for the design of experiments on establishing new constraints of dark matter and exotic interactions in the near future.
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Submitted 18 February, 2025;
originally announced February 2025.
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Critical properties in the non-Hermitian Aubry-Andre-Stark model
Authors:
Ji-Long Dong,
En-Wen Liang,
Shi-Yang Liu,
Guo-Qing Zhang,
Ling-Zhi Tang,
Dan-Wei Zhang
Abstract:
We explore the critical properties of the localization transition in the non-Hermitian Aubry-Andre-Stark (AAS) model with quasiperiodic and Stark potentials, where the non-Hermiticity comes from the nonreciprocal hopping. The localization length, the inverse participation ratio and the energy gap are adopted as the characteristic quantities. We perform the scaling analysis to derive the scaling fu…
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We explore the critical properties of the localization transition in the non-Hermitian Aubry-Andre-Stark (AAS) model with quasiperiodic and Stark potentials, where the non-Hermiticity comes from the nonreciprocal hopping. The localization length, the inverse participation ratio and the energy gap are adopted as the characteristic quantities. We perform the scaling analysis to derive the scaling functions of the three quantities with critical exponents in several critical regions, with respect to the quasiperiodic and Stark potentials and the nonreciprocal strength. We numerically verify the finite-size scaling forms and extract the critical exponents in different situations. Two groups of new critical exponents for the non-Hermitian AAS model and its pure Stark limit are obtained, which are distinct to those for the non-Hermitian Aubry-Andre model and their Hermitian counterparts. Our results indicate that the Hermitian and non-Hermitian AAS, Aubry-Andre, and Stark models belong to different universality classes. We demonstrate that these critical exponents are independent of the nonreciprocal strength, and remain the same in different critical regions and boundary conditions. Furthermore, we establish a hybrid scaling function with a hybrid exponent in the overlap region between the critical regions for the non-Hermitian AAS and Stark models.
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Submitted 13 May, 2025; v1 submitted 7 January, 2025;
originally announced January 2025.
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Post-selection shifts the transition frequency of helium in an atomic beam
Authors:
Jin-Lu Wen,
Jia-Dong Tang,
Ya-Nan Lv,
Yu R. Sun,
Chang-Ling Zou,
Jun-Feng Dong,
Shui-Ming Hu
Abstract:
Post-selecting output states in measurements can effectively amplify weak signals and improve precision. However, post-selection effects may also introduce unintended biases in precision measurements. Here, we investigate the influence of post-selection in the precision spectroscopy of the $2^3S - 2^3P$ transition of helium ($^4$He) using an atomic beam. We directly observe that post-selection bas…
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Post-selecting output states in measurements can effectively amplify weak signals and improve precision. However, post-selection effects may also introduce unintended biases in precision measurements. Here, we investigate the influence of post-selection in the precision spectroscopy of the $2^3S - 2^3P$ transition of helium ($^4$He) using an atomic beam. We directly observe that post-selection based on atomic positions causes a shift in the measured transition frequency, amounting to approximately -55 kHz. After accounting for this post-selection shift, we obtain a corrected frequency of $276,764,094,712.45 \pm 0.86$ kHz for the $2^3S_1 - 2^3P_0$ transition. Combining this result with existing data for $^3$He, we derive a new value for the difference in squared nuclear charge radii, $δr^2 [r_{h}^{2} - r_α^{2}] = 1.0733 \pm 0.0021$ fm$^2$. This value shows a $2.8σ$ deviation from measurements of muonic helium ions, potentially pointing to new physics that challenges lepton universality in quantum electrodynamics.
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Submitted 15 November, 2024;
originally announced November 2024.
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Quantum Mpemba effect of localization in the dissipative mosaic model
Authors:
J. W. Dong,
H. F. Mu,
M. Qin,
H. T. Cui
Abstract:
The quantum Mpemba effect in open quantum systems has been extensively studied, but a comprehensive understanding of this phenomenon remains elusive. In this paper, we conduct an analytical investigation of the dissipative dynamics of single excitations in the The mosaic model. Surprisingly, we discover that the presence of an asymptotic mobility edge, denoted as $E_c^{\infty}$, can lead to unique…
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The quantum Mpemba effect in open quantum systems has been extensively studied, but a comprehensive understanding of this phenomenon remains elusive. In this paper, we conduct an analytical investigation of the dissipative dynamics of single excitations in the The mosaic model. Surprisingly, we discover that the presence of an asymptotic mobility edge, denoted as $E_c^{\infty}$, can lead to unique dissipation behavior, serving as a hallmark of the quantum Mpemba effect. Especially, it is found that the energy level $E_c^{\infty}$ exhibits a global periodicity in the real configuration, which acts to inhibit dissipation in the system. Conversely, when the system deviates from $E_c^{\infty}$, the quasidisorder sets in, leading to increased dissipative effects due to the broken of periodicity. Furthermore, we find that the rate of dissipation is closely linked to the localization of the initial state. As a result, the quantum Mpemba effect can be observed clearly by a measure of localization.
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Submitted 18 February, 2025; v1 submitted 6 November, 2024;
originally announced November 2024.
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Amplification of light pulses with orbital angular momentum (OAM) in nitrogen ions lasing
Authors:
Haicheng Mei,
Jingsong Gao,
Kailu Wang,
Jiahao Dong,
Qihuang Gong,
Chengyin Wu,
Yunquan Liu,
Hongbing Jiang,
Yi Liu
Abstract:
Nitrogen ions pumped by intense femtosecond laser pulses give rise to optical amplification in the ultraviolet range. Here, we demonstrated that a seed light pulse carrying orbital angular momentum (OAM) can be significantly amplified in nitrogen plasma excited by a Gaussian femtosecond laser pulse. With the topological charge of +1 and -1, we observed an energy amplification of the seed light pul…
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Nitrogen ions pumped by intense femtosecond laser pulses give rise to optical amplification in the ultraviolet range. Here, we demonstrated that a seed light pulse carrying orbital angular momentum (OAM) can be significantly amplified in nitrogen plasma excited by a Gaussian femtosecond laser pulse. With the topological charge of +1 and -1, we observed an energy amplification of the seed light pulse by two orders of magnitude, while the amplified pulse carries the same OAM as the incident seed pulse. Moreover, we show that a spatial misalignment of the plasma amplifier with the OAM seed beam leads to an amplified emission of Gaussian mode without OAM, due to the special spatial profile of the OAM seed pulse that presents a donut-shaped intensity distribution. Utilizing this misalignment, we can implement an optical switch that toggles the output signal between Gaussian mode and OAM mode. This work not only certifies the phase transfer from the seed light to the amplified signal, but also highlights the important role of spatial overlap of the donut-shaped seed beam with the gain region of the nitrogen plasma for the achievement of OAM beam amplification.
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Submitted 10 July, 2023; v1 submitted 9 July, 2023;
originally announced July 2023.
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Biorthogonal Dynamical Quantum Phase Transitions in Non-Hermitian Systems
Authors:
Yecheng Jing,
Jian-Jun Dong,
Yu-Yu Zhang,
Zi-Xiang Hu
Abstract:
By utilizing biorthogonal bases, we develop a comprehensive framework for studying biorthogonal dynamical quantum phase transitions in non-Hermitian systems. With the help of the previously overlooked associated state, we define the automatically normalized biorthogonal Loschmidt echo. This approach is capable of handling arbitrary non-Hermitian systems with complex eigenvalues and naturally elimi…
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By utilizing biorthogonal bases, we develop a comprehensive framework for studying biorthogonal dynamical quantum phase transitions in non-Hermitian systems. With the help of the previously overlooked associated state, we define the automatically normalized biorthogonal Loschmidt echo. This approach is capable of handling arbitrary non-Hermitian systems with complex eigenvalues and naturally eliminates the negative value of Loschmidt rate obtained without the biorthogonal bases. Taking the non-Hermitian Su-Schrieffer-Heeger model as a concrete example, a $1/2$ change of dynamical topological order parameter in biorthogonal bases is observed which is not shown in self-normal bases. Furthermore, we discover that the periodicity of biorthogonal dynamical quantum phase transitions depends on whether the two-level subsystem at the critical momentum oscillates or reaches a steady state.
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Submitted 31 May, 2024; v1 submitted 6 July, 2023;
originally announced July 2023.
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Methane sensing in the mid-IR using short wave IR photon counting detectors via non-linear interferometry
Authors:
Arthur C. Cardoso,
Jinghan Dong,
Haichen Zhou,
Siddarth K. Joshi,
John G. Rarity
Abstract:
We demonstrate a novel MIR methane sensor shifting measurement wavelength to SWIR (1.55$μ$m) by using non-linear interferometry. The technique exploits the interference effects seen in three-wave mixing when pump, signal, and idler modes make a double pass through a nonlinear crystal. The method allows sensing at wavelengths where detectors are poor ($>$3$μ$m) and detection at wavelengths where ph…
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We demonstrate a novel MIR methane sensor shifting measurement wavelength to SWIR (1.55$μ$m) by using non-linear interferometry. The technique exploits the interference effects seen in three-wave mixing when pump, signal, and idler modes make a double pass through a nonlinear crystal. The method allows sensing at wavelengths where detectors are poor ($>$3$μ$m) and detection at wavelengths where photon counting sensitivity can be achieved. In a first experimental demonstration, we measured a small methane concentration inside a gas cell with high precision. This interferometer can be built in a compact design for field operations and potentially enable the detection of low concentrations of methane at up to 100m range. Signal-to-noise ratio calculations show that the method can outperform existing short wavelength ($\sim$1.65$μ$m) integrated path differential absorption direct sensing at high ($>$$10^{-4}$) non-linear gain.
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Submitted 21 May, 2024; v1 submitted 30 September, 2022;
originally announced September 2022.
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Towards merged-element transmons using silicon fins: the FinMET
Authors:
Aranya Goswami,
Anthony P. McFadden,
Tongyu Zhao,
Hadass S. Inbar,
Jason T. Dong,
Ruichen Zhao,
Corey Rae McRae,
Raymond W. Simmonds,
Christopher J. Palmstrøm,
David P. Pappas
Abstract:
A merged-element transmon (MET) device, based on silicon (Si) fins, is proposed and the first steps to form such a "FinMET" are demonstrated. This new application of fin technology capitalizes on the anisotropic etch of Si(111) relative to Si(110) to define atomically flat, high aspect ratio Si tunnel barriers with epitaxial superconductor contacts on the parallel side-wall surfaces. This process…
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A merged-element transmon (MET) device, based on silicon (Si) fins, is proposed and the first steps to form such a "FinMET" are demonstrated. This new application of fin technology capitalizes on the anisotropic etch of Si(111) relative to Si(110) to define atomically flat, high aspect ratio Si tunnel barriers with epitaxial superconductor contacts on the parallel side-wall surfaces. This process circumvents the challenges associated with the growth of low-loss insulating barriers on lattice matched superconductors. By implementing low-loss, intrinsic float-zone Si as the barrier material rather than commonly used, potentially lossy AlOx, the FinMET is expected to overcome problems with standard transmons by (1) reducing dielectric losses, (2) minimizing the formation of two-level system spectral features, (3) exhibiting greater control over barrier thickness and qubit frequency spread, especially when combined with commercial fin fabrication and atomic-layer digital etching; (4) potentially reducing the footprint by several orders of magnitude; and (5) allowing scalable fabrication. Here, as a first step to making such a device, the fabrication of Si fin capacitors on Si(110) substrates with shadow-deposited Al electrodes is demonstrated. These fin capacitors are then fabricated into lumped element resonator circuits and probed using low-temperature microwave measurements. Further thinning of silicon junctions towards the tunneling regime will enable the scalable fabrication of FinMET devices based on existing silicon technology, while simultaneously avoiding lossy amorphous dielectrics for the tunnel barriers.
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Submitted 1 July, 2022; v1 submitted 25 August, 2021;
originally announced August 2021.
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Topologically protected valley-dependent quantum photonic circuits
Authors:
Yang Chen,
Xin-Tao He,
Yu-Jie Cheng,
Hao-Yang Qiu,
Lan-Tian Feng,
Ming Zhang,
Dao-Xin Dai,
Guang-Can Guo,
Jian-Wen Dong,
Xi-Feng Ren
Abstract:
Topological photonics has been introduced as a powerful platform for integrated optics, since it can deal with robust light transport, and be further extended to the quantum world. Strikingly, valley-contrasting physics in topological photonic structures contributes to valley-related edge states, their unidirectional coupling, and even valley-dependent wave-division in topological junctions. Here,…
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Topological photonics has been introduced as a powerful platform for integrated optics, since it can deal with robust light transport, and be further extended to the quantum world. Strikingly, valley-contrasting physics in topological photonic structures contributes to valley-related edge states, their unidirectional coupling, and even valley-dependent wave-division in topological junctions. Here, we design and fabricate nanophotonic topological harpoon-shaped beam splitters (HSBSs) based on $120$-deg-bending interfaces and demonstrate the first on-chip valley-dependent quantum information process. Two-photon quantum interference, namely, HongOu-Mandel (HOM) interference with a high visibility of $0.956 \pm 0.006$, is realized with our 50/50 HSBS, which is constructed by two topologically distinct domain walls. Cascading this kind of HSBS together, we also demonstrate a simple quantum photonic circuit and generation of a path-entangled state. Our work shows that the photonic valley state can be used in quantum information processing, and it is possible to realize more complex quantum circuits with valley-dependent photonic topological insulators, which provides a novel method for on-chip quantum information processing.
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Submitted 11 March, 2021;
originally announced March 2021.
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Casimir Thrust Force on a Rotating Chiral Particle
Authors:
Jianhui Yu,
Wenjin Long,
Yu Zhang,
Yongliang Li,
Songqing Yang,
Wenguo Zhu,
Huadan Zheng,
Yi Xiao,
Jieyuan Tang,
Heyuan Guan,
Jiangli Dong,
Huihui Lu,
Wentao Qiu,
Jun Zhang,
Frank K Tittel,
Zhe Chen
Abstract:
In the work, the thermal and vacuum fluctuation is predicted capable of generating a Casimir thrust force on a rotating chiral particle, which will push or pull the particle along the rotation axis. The Casimir thrust force comes from two origins: i) the rotation-induced symmetry-breaking in the vacuum and thermal fluctuation and ii) the chiral cross-coupling between electric and magnetic fields a…
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In the work, the thermal and vacuum fluctuation is predicted capable of generating a Casimir thrust force on a rotating chiral particle, which will push or pull the particle along the rotation axis. The Casimir thrust force comes from two origins: i) the rotation-induced symmetry-breaking in the vacuum and thermal fluctuation and ii) the chiral cross-coupling between electric and magnetic fields and dipoles, which can convert the vacuum spin angular momentum (SAM) to the vacuum force. Using the fluctuation dissipation theorem (FDT), we derive the analytical expressions for the vacuum thrust force in dipolar approximation and the dependences of the force on rotation frequency, temperature and material optical properties are investigated. The work reveals a new mechanism to generate a vacuum force, which opens a new way to exploit zero-point energy of vacuum.
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Submitted 31 October, 2018; v1 submitted 19 October, 2018;
originally announced October 2018.
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Echo-Ramsey Interferometry with Motional Quantum States
Authors:
D. Hu,
L. X. Niu,
S. J. Jin,
X. Z. Chen,
G. J. Dong,
J. Schmiedmayer,
X. J. Zhou
Abstract:
Ramsey interferometers (RIs) using internal electronic or nuclear states find wide applications in science and engineering. We develop a matter wave Ramsey interferometer for motional quantum states exploiting the S- and D-bands of an optical lattice and identify the different de-phasing and de-coherence mechanisms. We implement a band echo technique, employing repeated $π$-pulses. This suppresses…
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Ramsey interferometers (RIs) using internal electronic or nuclear states find wide applications in science and engineering. We develop a matter wave Ramsey interferometer for motional quantum states exploiting the S- and D-bands of an optical lattice and identify the different de-phasing and de-coherence mechanisms. We implement a band echo technique, employing repeated $π$-pulses. This suppresses the de-phasing evolution and significantly increase the coherence time of the motional state interferometer by one order of magnitude. We identify thermal fluctuations as the main mechanism for the remaining decay contrast. Our demonstration of an echo-Ramsey interferometer with motional quantum states in an optical lattice has potential application in the study of quantum many body lattice dynamics, and motional qubits manipulation.
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Submitted 20 December, 2017;
originally announced December 2017.
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Greenberger-Horne-Zeilinger test for multi-dimension and arbitrary time nodes entangled histories
Authors:
Junkai Dong,
YiMing Chen,
Da Xu,
Zhang-qi Yin
Abstract:
Based on the framework of consistent history theory, the quantum entangled history was proposed in 2015 and experimentally verified through temporal Greenberger-Horne-Zeilinger (GHZ) test with $3$ time nodes in 2016. In this paper, we extend the temporal GHZ test to arbitrary time nodes and even system dimensions. Then, we define a witness to distinguish between the quantum entangled histories and…
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Based on the framework of consistent history theory, the quantum entangled history was proposed in 2015 and experimentally verified through temporal Greenberger-Horne-Zeilinger (GHZ) test with $3$ time nodes in 2016. In this paper, we extend the temporal GHZ test to arbitrary time nodes and even system dimensions. Then, we define a witness to distinguish between the quantum entangled histories and the classical histories. The minimums of the witness for the classical histories are calculated for arbitrary number of time nodes and the system dimensions $2$ and $\infty$. It is found that the minimums of the witness for the classical histories is always larger than the quantum entangled histories minimum $-1$. Only when both the number of time nodes and system dimensions approach to infinity, the minimum of the witness for classical and quantum entangled histories are identical.
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Submitted 13 August, 2017; v1 submitted 13 October, 2016;
originally announced October 2016.
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Control and Manipulation of Cold Atoms in Optical Tweezers
Authors:
Cecilia Muldoon,
Lukas Brandt,
Jian Dong,
Dustin Stuart,
Edouard Brainis,
Matthew Himsworth,
Axel Kuhn
Abstract:
Neutral atoms trapped by laser light are amongst the most promising candidates for storing and processing information in a quantum computer or simulator. The application certainly calls for a scalable and flexible scheme for addressing and manipulating the atoms. We have now made this a reality by implementing a fast and versatile method to dynamically control the position of neutral atoms trapped…
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Neutral atoms trapped by laser light are amongst the most promising candidates for storing and processing information in a quantum computer or simulator. The application certainly calls for a scalable and flexible scheme for addressing and manipulating the atoms. We have now made this a reality by implementing a fast and versatile method to dynamically control the position of neutral atoms trapped in optical tweezers. The tweezers result from a spatial light modulator (SLM) controlling and shaping a large number of optical dipole-force traps. Trapped atoms adapt to any change in the potential landscape, such that one can re-arrange and randomly access individual sites within atom-trap arrays.
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Submitted 21 March, 2012; v1 submitted 3 September, 2011;
originally announced September 2011.
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Applications of density matrix in the fractional quantum mechanics
Authors:
Jianping Dong
Abstract:
The many-body space fractional quantum system is studied using the density matrix method. We give the new results of the Thomas-Fermi model, and obtain the quantum pressure of the free electron gas. We also show the validity of the Hohenberg-Kohn theory in the space fractional quantum mechanics and generalize the density functional theory to the fractional quantum mechanics.
The many-body space fractional quantum system is studied using the density matrix method. We give the new results of the Thomas-Fermi model, and obtain the quantum pressure of the free electron gas. We also show the validity of the Hohenberg-Kohn theory in the space fractional quantum mechanics and generalize the density functional theory to the fractional quantum mechanics.
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Submitted 22 December, 2010;
originally announced December 2010.
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Spatial Light Modulators for the Manipulation of Individual Atoms
Authors:
Lukas Brandt,
Cecilia Muldoon,
Tobias Thiele,
Jian Dong,
Edouard Brainis,
Axel Kuhn
Abstract:
We propose a novel dipole trapping scheme using spatial light modulators (SLM) for the manipulation of individual atoms. The scheme uses a high numerical aperture microscope to map the intensity distribution of a SLM onto a cloud of cold atoms. The regions of high intensity act as optical dipole force traps. With a SLM fast enough to modify the trapping potential in real time, this technique is we…
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We propose a novel dipole trapping scheme using spatial light modulators (SLM) for the manipulation of individual atoms. The scheme uses a high numerical aperture microscope to map the intensity distribution of a SLM onto a cloud of cold atoms. The regions of high intensity act as optical dipole force traps. With a SLM fast enough to modify the trapping potential in real time, this technique is well suited for the controlled addressing and manipulation of arbitrarily selected atoms.
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Submitted 5 August, 2010;
originally announced August 2010.
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The readout of the fullerene-based quantum computing by a scanning tunneling microscope
Authors:
M. Feng,
G. J. Dong,
B. Hu
Abstract:
We consider to detect the electron spin of a doped atom, i.e., a nitrogen or a phosphorus, caged in a fullerene by currently available technique of the scanning tunneling microscope (STM), which actually corresponds to the readout of a qubit in the fullerene-based quantum computing. Under the conditions of polarized STM current and Coulomb blockade, we investigate the tunneling matrix elements i…
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We consider to detect the electron spin of a doped atom, i.e., a nitrogen or a phosphorus, caged in a fullerene by currently available technique of the scanning tunneling microscope (STM), which actually corresponds to the readout of a qubit in the fullerene-based quantum computing. Under the conditions of polarized STM current and Coulomb blockade, we investigate the tunneling matrix elements involving the exchange coupling between the tunneling polarized electrons and the encapsulated polarized electron, and calculate the variation of the tunneling current with respect to different orientations of the encapsulated electron spin. The experimental feasibility of our scheme is discussed under the consideration of some imperfect factors.
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Submitted 10 October, 2006;
originally announced October 2006.