-
Control of Photon Dynamics in Non-Euclidean Polygonal Microcavities by Joint Geometric Curvatures
Authors:
Yechun Ding,
Yongsheng Wang,
Peng Li,
Yaxin Guo,
Yanpeng Zhang,
Feng Yun,
Feng Li
Abstract:
Non-Euclidean geometry has recently emerged as a powerful tool, offering new insights and applications in optical microcavities supporting Whispering Gallery Modes (WGMs). In this study, we extend the concept of polygonal microcavities to non-Euclidean spaces by developing a unified model that incorporates a joint geometric parameter of curvatures. This system uncovers a range of unexplored phenom…
▽ More
Non-Euclidean geometry has recently emerged as a powerful tool, offering new insights and applications in optical microcavities supporting Whispering Gallery Modes (WGMs). In this study, we extend the concept of polygonal microcavities to non-Euclidean spaces by developing a unified model that incorporates a joint geometric parameter of curvatures. This system uncovers a range of unexplored phenomena, mechanisms, and concepts that are unique to curved spaces. Notably, we observe dissipative states characterized by hyperbolic fixed points (HFPs) that appear exclusively in non-Euclidean scenarios, leading to the formation of phase diagrams within the parametric space of curvatures. Our results reveal phase transitions across geometric boundaries, marked by abrupt changes in the cavity quality factor. These transitions are strongly influenced by the wavelike nature of photon trajectories, offering intriguing insights into quantum chaos within curved spaces. Additionally, we discover that cavities with geodesic side lines exhibit a remarkable symmetry-driven avoidance of such phase transitions, highlighting the profound connection between physical dynamics and spatial geometry. Our findings establish a promising platform for optical simulations of non-Euclidean quantum chaos and open up potential applications in on-chip photonic devices.
△ Less
Submitted 1 May, 2025;
originally announced May 2025.
-
Vectorial Symmetry Decoding with Single-Particle Precision via Room-Temperature Lanthanide Luminescence Polarimetry
Authors:
Peng Li,
Yaxin Guo,
Yaoxu Yan,
Bingzhu Zheng,
Wenchao Zhang,
Jingai Mu,
Fu Liu,
Yanpeng Zhang,
Feng Yun,
Rongqian Wu,
Yi Lyu,
Renren Deng,
Feng Li
Abstract:
Determining the local symmetry of luminescent centers in crystals is critical for understanding and controlling their optical transitions, yet current methods are limited by stringent experimental requirements and ambiguous symmetry assignments. Here, we develop a robust computational electromagnetics framework that directly connect the local symmetry and chirality of rare-earth-doped single cryst…
▽ More
Determining the local symmetry of luminescent centers in crystals is critical for understanding and controlling their optical transitions, yet current methods are limited by stringent experimental requirements and ambiguous symmetry assignments. Here, we develop a robust computational electromagnetics framework that directly connect the local symmetry and chirality of rare-earth-doped single crystals to the polarization states of their emitted light. This framework is experimentally validated through the precise determination of point and space group symmetries using high-resolution, polarization-resolved micro-photoluminescence (μ-PL) spectra. Unlike conventional approaches that usually rely on analyzing multiple transitions at cryogenic temperatures, our technique operates at room temperature, requires only a single optical transition, and enables accurate orientation of symmetry axes. This enables deterministic polarization control of nano-emitters by tailoring symmetry groups and selecting appropriate transition dipoles, eliminating the need for bulky or complex photonic structures. Additionally, we demonstrate the function of bio-sensing, via determining single particle orientations in complex cellular environments using minimal polarization measurements. These results pave the way for advances in energy transfer systems, ultra-bright rare-earth nanocrystals, nanophotonic materials, and real-time single-particle tracking in biological contexts.
△ Less
Submitted 31 July, 2025; v1 submitted 13 January, 2025;
originally announced January 2025.
-
Dual orthogonally-polarized lasing assisted by imaginary Fermi arcs in organic microcavities
Authors:
Teng Long,
Jiahuan Ren,
Peng Li,
Feng Yun,
Guillaume Malpuech,
Dmitry Solnyshkov,
Hongbing Fu,
Feng Li,
Qing Liao
Abstract:
The polarization control of micro/nano lasers is an important topic in nanophotonics. Up to now, the simultaneous generation of two distinguishable orthogonally-polarized lasing modes from a single organic microlaser remains a critical challenge. Here, we demonstrate simultaneously orthogonally-polarized dual lasing from a microcavity filled with an organic single crystal exhibiting selective stro…
▽ More
The polarization control of micro/nano lasers is an important topic in nanophotonics. Up to now, the simultaneous generation of two distinguishable orthogonally-polarized lasing modes from a single organic microlaser remains a critical challenge. Here, we demonstrate simultaneously orthogonally-polarized dual lasing from a microcavity filled with an organic single crystal exhibiting selective strong coupling. We show that the non-Hermiticity due to polarization-dependent losses leads to the formation of real and imaginary Fermi arcs with exceptional points. Simultaneous orthogonally-polarized lasing becomes possible thanks to the eigenstate mixing by the photonic spin-orbit coupling at the imaginary Fermi arcs. Our work provides a novel way to develop linearly-polarized lasers and paves the way for the future fundamental research in topological photonics, non-Hermitian optics, and other fields.
△ Less
Submitted 12 March, 2024;
originally announced March 2024.
-
Tailoring chaotic motion of microcavity photons in ray and wave dynamics by tuning the curvature of space
Authors:
Wei Lin,
Yechun Ding,
Yongsheng Wang,
Yanpeng Zhang,
Feng Yun,
Feng Li
Abstract:
Microcavity photon dynamics in curved space is an emerging interesting area at the crossing point of nanophotonics, chaotic science and non-Euclidean geometry. We report the sharp difference between the regular and chaotic motions of cavity photons subjected to the varying space curvature. While the island modes of regular motion rise in the phase diagram in the curved space, the chaotic modes sho…
▽ More
Microcavity photon dynamics in curved space is an emerging interesting area at the crossing point of nanophotonics, chaotic science and non-Euclidean geometry. We report the sharp difference between the regular and chaotic motions of cavity photons subjected to the varying space curvature. While the island modes of regular motion rise in the phase diagram in the curved space, the chaotic modes show special mechanisms to adapt to the space curvature, including the fast diffusion of ray dynamics, and the localization and hybridization of the Husimi wavepackets among different periodic orbits. These obser-vations are unique effects enabled by the combination of the chaotic trajectory, the wave nature of light and the non-Euclidean orbital motion, and therefore make the system a versatile optical simulator for chaotic science under quan-tum mechanics in curved space-time.
△ Less
Submitted 17 January, 2024;
originally announced January 2024.
-
Effective potential engineering by emergent anisotropy in a tunable open-access microcavity
Authors:
Yiming Li,
Xiaoxuan Luo,
Yaxin Guo,
Jiahuan Ren,
Teng Long,
Bohao Wang,
Yin Cai,
Chaowei Guo,
Yuanbin Qin,
Hongbing Fu,
Yanpeng Zhang,
Feng Yun,
Qing Liao,
Feng Li
Abstract:
Photonic spin-orbit (SO) coupling is an important physical mechanism leading to numerous interesting phenomena in the systems of microcavity photons and exciton-polaritons. We report the effect of SO coupling in a tunable open-access microcavity embedded with anisotropic active media. The SO coupling associated with the TE-TM splitting results in an emergent anisotropy, which further leads to fine…
▽ More
Photonic spin-orbit (SO) coupling is an important physical mechanism leading to numerous interesting phenomena in the systems of microcavity photons and exciton-polaritons. We report the effect of SO coupling in a tunable open-access microcavity embedded with anisotropic active media. The SO coupling associated with the TE-TM splitting results in an emergent anisotropy, which further leads to fine energy splittings allowing clear observation of the full set of eigenstates, in sharp contrast with the isotropic situation which leads to the isotropic eigenstates of spin vortices. We show that the photonic potential can be engineered by playing with the relation between the emergent anisotropy and the cavity ellipticity. All the experimental results are well reproduced by the degenerate perturbation theory. Our results constitute a significant extension to the research field of microcavity spinoptronics, with potential applications in polarization control and optical property measurement of photonic devices and materials.
△ Less
Submitted 11 October, 2023;
originally announced October 2023.
-
Magneto-transport and electronic structures in MoSi$_2$ bulks and thin films with different orientations
Authors:
W. Afzal,
F. Yun,
Z. Li,
Z. Yue,
W. Zhao,
L. Sang,
G. Yang,
Y. He,
G. Peleckis,
M. Fuhrer,
X. Wang
Abstract:
We report a comprehensive study of magneto-transport properties in MoSi$_2$ bulk and thin films. Textured MoSi$_2$ thin films of around 70 nm were deposited on silicon substrates with different orientations. Giant magnetoresistance of 1000% was observed in sintered bulk samples while MoSi$_2$ single crystals exhibit a magnetoresistance (MR) value of 800% at low temperatures. At the low temperature…
▽ More
We report a comprehensive study of magneto-transport properties in MoSi$_2$ bulk and thin films. Textured MoSi$_2$ thin films of around 70 nm were deposited on silicon substrates with different orientations. Giant magnetoresistance of 1000% was observed in sintered bulk samples while MoSi$_2$ single crystals exhibit a magnetoresistance (MR) value of 800% at low temperatures. At the low temperatures, the MR of the textured thin films show weak anti-localization behaviour owing to the spin orbit coupling effects. Our first principle calculation show the presence of surface states in this material. The resistivity of all the MoSi$_2$ thin films is significantly low and nearly independent of the temperature, which is important for electronic devices.
△ Less
Submitted 19 July, 2023;
originally announced July 2023.
-
Discovery of voltage induced superfluid-like penetration effect in liquid metals at room temperature
Authors:
Frank F. Yun,
Zhenwei Yu,
Yahua He,
Lei Jiang,
Haoshuang Gu,
Zhao Wang,
Xiaolin Wang
Abstract:
We have discovered that room temperature liquid metal is capable of penetrating through macro- and microporous materials by applying a voltage. In this work, we demonstrate the liquid metal penetration effect in various porous materials such as tissue paper, thick and fine sponges, fabrics, and meshes. The penetration effect mimics one of the three well-known superfluid properties of liquid helium…
▽ More
We have discovered that room temperature liquid metal is capable of penetrating through macro- and microporous materials by applying a voltage. In this work, we demonstrate the liquid metal penetration effect in various porous materials such as tissue paper, thick and fine sponges, fabrics, and meshes. The penetration effect mimics one of the three well-known superfluid properties of liquid helium superfluid that only occur at near-zero Kelvin. The underlying mechanism is that the high surface tension of liquid metal can be significantly reduced to near-zero due to the voltage induced oxidation of the liquid metal surface in a solution. It is the extremely low surface tension and gravity that cause the liquid metal to superwet the solid surface, leading to the penetration phenomena. Our findings offer new opportunities for novel microfluidic applications and could promote further discovery of more exotic fluid states of liquid metals.
△ Less
Submitted 31 March, 2019;
originally announced July 2019.