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Statistical Reproducibility of Selective Area Grown InAs Nanowire Devices
Authors:
Dāgs Olšteins,
Gunjan Nagda,
Damon J. Carrad,
Daria V. Beznasyuk,
Christian E. N. Petersen,
Sara Martí-Sánchez,
Jordi Arbiol,
Thomas Sand Jespersen
Abstract:
New approaches such as selective area growth, where crystal growth is lithographically controlled, allow the integration of bottom-up grown semiconductor nanomaterials in large-scale classical and quantum nanoelectronics. This calls for assessment and optimization of the reproducibility between individual components. We quantify the structural and electronic statistical reproducibility within larg…
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New approaches such as selective area growth, where crystal growth is lithographically controlled, allow the integration of bottom-up grown semiconductor nanomaterials in large-scale classical and quantum nanoelectronics. This calls for assessment and optimization of the reproducibility between individual components. We quantify the structural and electronic statistical reproducibility within large arrays of nominally identical selective area growth InAs nanowires. The distribution of structural parameters is acquired through comprehensive atomic force microscopy studies and transmission electron microscopy. These are compared to the statistical distributions of the cryogenic electrical properties of 256 individual SAG nanowire field effect transistors addressed using cryogenic multiplexer circuits. Correlating measurements between successive thermal cycles allows distinguishing between the contributions of surface impurity scattering and fixed structural properties to device reproducibility. The results confirm the potential of SAG nanomaterials, and the methodologies for quantifying statistical metrics are essential for further optimization of reproducibility.
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Submitted 22 May, 2024; v1 submitted 10 January, 2024;
originally announced January 2024.
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Cryogenic Multiplexing with Bottom-Up Nanowires
Authors:
Dāgs Olšteins,
Gunjan Nagda,
Damon J. Carrad,
Daria V. Beznasiuk,
Christian E. N. Petersen,
Sara Martí-Sánchez,
Jordi Arbiol,
Thomas Sand Jespersen
Abstract:
Bottom-up grown nanomaterials play an integral role in the development of quantum technologies. Among these, semiconductor nanowires (NWs) are widely used in proof-of-principle experiments, however, difficulties in parallel processing of conventionally-grown NWs makes scalability unfeasible. Here, we harness selective area growth (SAG) to remove this road-block. We demonstrate large scale integrat…
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Bottom-up grown nanomaterials play an integral role in the development of quantum technologies. Among these, semiconductor nanowires (NWs) are widely used in proof-of-principle experiments, however, difficulties in parallel processing of conventionally-grown NWs makes scalability unfeasible. Here, we harness selective area growth (SAG) to remove this road-block. We demonstrate large scale integrated SAG NW circuits consisting of 512 channel multiplexer/demultiplexer pairs, incorporating thousands of interconnected SAG NWs operating under deep cryogenic conditions. Multiplexers enable a range of new strategies in quantum device research and scaling by increase the device count while limiting the number of connections between room-temperature control electronics and the cryogenic samples. As an example of this potential we perform a statistical characterization of large arrays of identical SAG quantum dots thus establishing the feasibility of applying cross-bar gating strategies for efficient scaling of future SAG quantum circuits.
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Submitted 25 April, 2023;
originally announced April 2023.
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Spectroscopy of the 1001 nm transition in atomic dysprosium
Authors:
Niels Petersen,
Marcel Trümper,
Patrick Windpassinger
Abstract:
We report on spectroscopy of cold dysprosium atoms on the $1001\,\mathrm{nm}$ transition and present measurements of the excited state lifetime which is at least $87.2(6.7)\,\mathrm{ms}$ long. Due to the long excited state lifetime we are able to measure the ratio of the excited state polarizability to the ground state polarizability at $1064\,\mathrm{nm}$ to be $0.828(0.129)$ by parametric heatin…
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We report on spectroscopy of cold dysprosium atoms on the $1001\,\mathrm{nm}$ transition and present measurements of the excited state lifetime which is at least $87.2(6.7)\,\mathrm{ms}$ long. Due to the long excited state lifetime we are able to measure the ratio of the excited state polarizability to the ground state polarizability at $1064\,\mathrm{nm}$ to be $0.828(0.129)$ by parametric heating in an optical dipole trap. In addition we measure the isotope shifts of the three most abundant bosonic isotopes of dysprosium on the $1001\,\mathrm{nm}$ transition with an accuracy better than $30\,\mathrm{kHz}$.
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Submitted 10 September, 2019; v1 submitted 12 July, 2019;
originally announced July 2019.
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Sawtooth wave adiabatic passage slowing of dysprosium
Authors:
Niels Petersen,
Florian Mühlbauer,
Lykourgos Bougas,
Arijit Sharma,
Dmitry Budker,
Patrick Windpassinger
Abstract:
We report on sawtooth wave adiabatic passage (SWAP) slowing of bosonic and fermionic dysprosium isotopes by using a 136 kHz wide transition at 626 nm. A beam of precooled atoms is further decelerated in one dimension by the SWAP force and the amount of atoms at near zero velocity is measured. We demonstrate that the SWAP slowing can be twice as fast as in a conventional optical molasses operated o…
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We report on sawtooth wave adiabatic passage (SWAP) slowing of bosonic and fermionic dysprosium isotopes by using a 136 kHz wide transition at 626 nm. A beam of precooled atoms is further decelerated in one dimension by the SWAP force and the amount of atoms at near zero velocity is measured. We demonstrate that the SWAP slowing can be twice as fast as in a conventional optical molasses operated on the same transition. In addition, we investigate the parameter range for which the SWAP force is efficiently usable in our set-up, and relate the results to the adiabaticity condition. Furthermore, we add losses to the hyperfine ground-state population of fermionic dysprosium during deceleration and observe more robust slowing with SWAP compared to slowing with the radiation pressure force.
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Submitted 17 September, 2018;
originally announced September 2018.
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Systematic optimization of laser cooling of dysprosium
Authors:
Florian Mühlbauer,
Niels Petersen,
Carina Baumgärtner,
Lena Maske,
Patrick Windpassinger
Abstract:
We report on an apparatus for cooling and trapping of neutral dysprosium. We characterize and optimize the performance of our Zeeman slower and 2D molasses cooling of the atomic beam by means of Doppler spectroscopy on a 136 kHz broad transition at 626 nm. Furthermore, we demonstrate the characterization and optimization procedure for the loading phase of a magneto-optical trap (MOT) by increasing…
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We report on an apparatus for cooling and trapping of neutral dysprosium. We characterize and optimize the performance of our Zeeman slower and 2D molasses cooling of the atomic beam by means of Doppler spectroscopy on a 136 kHz broad transition at 626 nm. Furthermore, we demonstrate the characterization and optimization procedure for the loading phase of a magneto-optical trap (MOT) by increasing the effective laser linewidth by sideband modulation. After optimization of the MOT compression phase, we cool and trap up to $10^9$ atoms within 3 seconds in the MOT at temperatures of 9 μK and phase space densities of $1.7 \cdot 10^{-5}$, which constitutes an ideal starting point for loading the atoms into an optical dipole trap and for subsequent forced evaporative cooling.
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Submitted 5 April, 2018;
originally announced April 2018.