1
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Costa A, Baumgartner C, Reinhardt S, Berger J, Gronin S, Gardner GC, Lindemann T, Manfra MJ, Fabian J, Kochan D, Paradiso N, Strunk C. Sign reversal of the Josephson inductance magnetochiral anisotropy and 0-π-like transitions in supercurrent diodes. Nat Nanotechnol 2023; 18:1266-1272. [PMID: 37430040 DOI: 10.1038/s41565-023-01451-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Accepted: 06/09/2023] [Indexed: 07/12/2023]
Abstract
The recent discovery of the intrinsic supercurrent diode effect, and its prompt observation in a rich variety of systems, has shown that non-reciprocal supercurrents naturally emerge when both space-inversion and time-inversion symmetries are broken. In Josephson junctions, non-reciprocal supercurrent can be conveniently described in terms of spin-split Andreev states. Here we demonstrate a sign reversal of the Josephson inductance magnetochiral anisotropy, a manifestation of the supercurrent diode effect. The asymmetry of the Josephson inductance as a function of the supercurrent allows us to probe the current-phase relation near equilibrium, and to probe jumps in the junction ground state. Using a minimal theoretical model, we can then link the sign reversal of the inductance magnetochiral anisotropy to the so-called 0-π-like transition, a predicted but still elusive feature of multichannel junctions. Our results demonstrate the potential of inductance measurements as sensitive probes of the fundamental properties of unconventional Josephson junctions.
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Affiliation(s)
- A Costa
- Institut für Theoretische Physik, University of Regensburg, Regensburg, Germany
| | - C Baumgartner
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, Regensburg, Germany
| | - S Reinhardt
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, Regensburg, Germany
| | - J Berger
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, Regensburg, Germany
| | - S Gronin
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
| | - T Lindemann
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA
| | - M J Manfra
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA
- School of Materials Engineering, Purdue University, West Lafayette, IN, USA
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA
| | - J Fabian
- Institut für Theoretische Physik, University of Regensburg, Regensburg, Germany
| | - D Kochan
- Institut für Theoretische Physik, University of Regensburg, Regensburg, Germany
- Institute of Physics, Slovak Academy of Sciences, Bratislava, Slovakia
| | - N Paradiso
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, Regensburg, Germany.
| | - C Strunk
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, Regensburg, Germany
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2
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Banerjee A, Lesser O, Rahman MA, Thomas C, Wang T, Manfra MJ, Berg E, Oreg Y, Stern A, Marcus CM. Local and Nonlocal Transport Spectroscopy in Planar Josephson Junctions. Phys Rev Lett 2023; 130:096202. [PMID: 36930915 DOI: 10.1103/physrevlett.130.096202] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 01/11/2023] [Indexed: 06/18/2023]
Abstract
We report simultaneously acquired local and nonlocal transport spectroscopy in a phase-biased planar Josephson junction based on an epitaxial InAs-Al hybrid two-dimensional heterostructure. Quantum point contacts at the junction ends allow measurement of the 2×2 matrix of local and nonlocal tunneling conductances as a function of magnetic field along the junction, phase difference across the junction, and carrier density. A closing and reopening of a gap was observed in both the local and nonlocal tunneling spectra as a function of magnetic field. For particular tunings of junction density, gap reopenings were accompanied by zero-bias conductance peaks (ZBCPs) in local conductances. End-to-end correlation of gap reopening was strong, while correlation of local ZBCPs was weak. A model of the device, with disorder treated phenomenologically, shows comparable conductance matrix behavior associated with a topological phase transition. Phase dependence helps distinguish possible origins of the ZBCPs.
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Affiliation(s)
- A Banerjee
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - O Lesser
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel 76100
| | - M A Rahman
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - C Thomas
- Department of Physics and Astronomy, and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 USA
| | - T Wang
- Department of Physics and Astronomy, and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 USA
| | - M J Manfra
- Department of Physics and Astronomy, and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 USA
- School of Materials Engineering, and School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 USA
| | - E Berg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel 76100
| | - Y Oreg
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel 76100
| | - Ady Stern
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot, Israel 76100
| | - C M Marcus
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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3
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Nakamura J, Liang S, Gardner GC, Manfra MJ. Half-Integer Conductance Plateau at the ν=2/3 Fractional Quantum Hall State in a Quantum Point Contact. Phys Rev Lett 2023; 130:076205. [PMID: 36867801 DOI: 10.1103/physrevlett.130.076205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
The ν=2/3 fractional quantum Hall state is the hole-conjugate state to the primary Laughlin ν=1/3 state. We investigate transmission of edge states through quantum point contacts fabricated on a GaAs/AlGaAs heterostructure designed to have a sharp confining potential. When a small but finite bias is applied, we observe an intermediate conductance plateau with G=0.5(e^{2}/h). This plateau is observed in multiple QPCs, and persists over a significant range of magnetic field, gate voltage, and source-drain bias, making it a robust feature. Using a simple model that considers scattering and equilibration between counterflowing charged edge modes, we find this half-integer quantized plateau to be consistent with full reflection of an inner counterpropagating -1/3 edge mode while the outer integer mode is fully transmitted. In a QPC fabricated on a different heterostructure which has a softer confining potential, we instead observe an intermediate conductance plateau at G=(1/3)(e^{2}/h). These results provide support for a model at ν=2/3 in which the edge transitions from a structure having an inner upstream -1/3 charge mode and outer downstream integer mode to a structure with two downstream 1/3 charge modes when the confining potential is tuned from sharp to soft and disorder prevails.
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Affiliation(s)
- J Nakamura
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - S Liang
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Lab West Lafayette, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Lab West Lafayette, West Lafayette, Indiana 47907, USA
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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4
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Baumgartner C, Fuchs L, Costa A, Picó-Cortés J, Reinhardt S, Gronin S, Gardner GC, Lindemann T, Manfra MJ, Faria Junior PE, Kochan D, Fabian J, Paradiso N, Strunk C. Effect of Rashba and Dresselhaus spin-orbit coupling on supercurrent rectification and magnetochiral anisotropy of ballistic Josephson junctions. J Phys Condens Matter 2022; 34:154005. [PMID: 35051919 DOI: 10.1088/1361-648x/ac4d5e] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Simultaneous breaking of inversion- and time-reversal symmetry in Josephson junction (JJ) leads to a possible violation of theI(φ) = -I(-φ) equality for the current-phase relation. This is known as anomalous Josephson effect and it produces a phase shiftφ0in sinusoidal current-phase relations. In ballistic JJs with non-sinusoidal current phase relation the observed phenomenology is much richer, including the supercurrent diode effect and the magnetochiral anisotropy (MCA) of Josephson inductance. In this work, we present measurements of both effects on arrays of JJs defined on epitaxial Al/InAs heterostructures. We show that the orientation of the current with respect to the lattice affects the MCA, possibly as the result of a finite Dresselhaus component. In addition, we show that the two-fold symmetry of the Josephson inductance reflects in the activation energy for phase slips.
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Affiliation(s)
- C Baumgartner
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - L Fuchs
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - A Costa
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - Jordi Picó-Cortés
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - S Reinhardt
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - S Gronin
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 United States of America
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 United States of America
| | - G C Gardner
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 United States of America
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 United States of America
| | - T Lindemann
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 United States of America
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907 United States of America
| | - M J Manfra
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 United States of America
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 United States of America
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907 United States of America
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907 United States of America
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 United States of America
| | - P E Faria Junior
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - D Kochan
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - J Fabian
- Institut für Theoretische Physik, University of Regensburg, 93040 Regensburg, Germany
| | - N Paradiso
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
| | - C Strunk
- Institut für Experimentelle und Angewandte Physik, University of Regensburg, 93040 Regensburg, Germany
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5
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Nakamura J, Liang S, Gardner GC, Manfra MJ. Impact of bulk-edge coupling on observation of anyonic braiding statistics in quantum Hall interferometers. Nat Commun 2022; 13:344. [PMID: 35039497 PMCID: PMC8763912 DOI: 10.1038/s41467-022-27958-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 12/20/2021] [Indexed: 11/29/2022] Open
Abstract
Quantum Hall interferometers have been used to probe fractional charge and statistics of quasiparticles. We present measurements of a small Fabry-Perot interferometer in which the electrostatic coupling constants which affect interferometer behavior can be determined experimentally. Near the center of the ν = 1/3 state this device exhibits Aharonov-Bohm interference interrupted by a few discrete phase jumps, and Φ0 oscillations at higher and lower magnetic fields, consistent with theoretical predictions for detection of anyonic statistics. We estimate the electrostatic parameters KI and KIL by two methods: using the ratio of oscillation periods in compressible versus incompressible regions, and from finite-bias conductance measurements. We find that the extracted KI and KIL can account for the deviation of the phase jumps from the theoretical anyonic phase θa = 2π/3. At integer states, we find that KI and KIL can account for the Aharonov-Bohm and Coulomb-dominated behavior of different edge states.
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Affiliation(s)
- J Nakamura
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
| | - S Liang
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA
- Microsoft Quantum Lab West Lafayette, West Lafayette, IN, USA
| | - M J Manfra
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, USA.
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, USA.
- Microsoft Quantum Lab West Lafayette, West Lafayette, IN, USA.
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, USA.
- School of Materials Engineering, Purdue University, West Lafayette, IN, USA.
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6
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Gupta A, Heremans JJ, Kataria G, Chandra M, Fallahi S, Gardner GC, Manfra MJ. Hydrodynamic and Ballistic Transport over Large Length Scales in GaAs/AlGaAs. Phys Rev Lett 2021; 126:076803. [PMID: 33666460 DOI: 10.1103/physrevlett.126.076803] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 11/09/2020] [Accepted: 01/21/2021] [Indexed: 05/07/2023]
Abstract
We study hydrodynamic and ballistic transport regimes through nonlocal resistance measurements and high-resolution kinetic simulations in a mesoscopic structure on a high-mobility two-dimensional electron system in a GaAs/AlGaAs heterostructure. We evince the existence of collective transport phenomena in both regimes and demonstrate that negative nonlocal resistances and current vortices are not exclusive to only the hydrodynamic regime. The combined experiments and simulations highlight the importance of device design, measurement schemes, and one-to-one modeling of experimental devices to demarcate various transport regimes.
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Affiliation(s)
- Adbhut Gupta
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - J J Heremans
- Department of Physics, Virginia Tech, Blacksburg, Virginia 24061, USA
| | - Gitansh Kataria
- Research Division, Quazar Technologies, Sarvapriya Vihar, New Delhi 110016, India
| | - Mani Chandra
- Research Division, Quazar Technologies, Sarvapriya Vihar, New Delhi 110016, India
| | - S Fallahi
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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7
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Fu X, Huang Y, Shi Q, Shklovskii BI, Zudov MA, Gardner GC, Manfra MJ. Hidden Quantum Hall Stripes in Al_{x}Ga_{1-x}As/Al_{0.24}Ga_{0.76}As Quantum Wells. Phys Rev Lett 2020; 125:236803. [PMID: 33337202 DOI: 10.1103/physrevlett.125.236803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Accepted: 10/30/2020] [Indexed: 06/12/2023]
Abstract
We report on transport signatures of hidden quantum Hall stripe (hQHS) phases in high (N>2) half-filled Landau levels of Al_{x}Ga_{1-x}As/Al_{0.24}Ga_{0.76}As quantum wells with varying Al mole fraction x<10^{-3}. Residing between the conventional stripe phases (lower N) and the isotropic liquid phases (higher N), where resistivity decreases as 1/N, these hQHS phases exhibit isotropic and N-independent resistivity. Using the experimental phase diagram, we establish that the stripe phases are more robust than theoretically predicted, calling for improved theoretical treatment. We also show that, unlike conventional stripe phases, the hQHS phases do not occur in ultrahigh mobility GaAs quantum wells but are likely to be found in other systems.
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Affiliation(s)
- X Fu
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Yi Huang
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Q Shi
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - B I Shklovskii
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M A Zudov
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - G C Gardner
- Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering and School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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8
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Whiticar AM, Fornieri A, O'Farrell ECT, Drachmann ACC, Wang T, Thomas C, Gronin S, Kallaher R, Gardner GC, Manfra MJ, Marcus CM, Nichele F. Coherent transport through a Majorana island in an Aharonov-Bohm interferometer. Nat Commun 2020; 11:3212. [PMID: 32587242 PMCID: PMC7316771 DOI: 10.1038/s41467-020-16988-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Accepted: 05/17/2020] [Indexed: 11/29/2022] Open
Abstract
Majorana zero modes are leading candidates for topological quantum computation due to non-local qubit encoding and non-abelian exchange statistics. Spatially separated Majorana modes are expected to allow phase-coherent single-electron transport through a topological superconducting island via a mechanism referred to as teleportation. Here we experimentally investigate such a system by patterning an elongated epitaxial InAs-Al island embedded in an Aharonov-Bohm interferometer. With increasing parallel magnetic field, a discrete sub-gap state in the island is lowered to zero energy yielding persistent 1e-periodic Coulomb blockade conductance peaks (e is the elementary charge). In this condition, conductance through the interferometer is observed to oscillate in a perpendicular magnetic field with a flux period of h/e (h is Planck’s constant), indicating coherent transport of single electrons through the islands, a signature of electron teleportation via Majorana modes. Theories predict teleportation of phase-coherent single electrons through a topological superconducting island. Here, the authors report persistent Coulomb blockade conductance peaks due to coherent transport of single electrons through patterned InAs-Al islands embedded in an Aharonov-Bohm interferometer.
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Affiliation(s)
- A M Whiticar
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen and Microsoft Quantum Lab Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark
| | - A Fornieri
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen and Microsoft Quantum Lab Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark
| | - E C T O'Farrell
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen and Microsoft Quantum Lab Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark
| | - A C C Drachmann
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen and Microsoft Quantum Lab Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark
| | - T Wang
- Department of Physics and Astronomy and Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, IN, 47907, USA.,Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
| | - C Thomas
- Department of Physics and Astronomy and Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, IN, 47907, USA.,Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
| | - S Gronin
- Department of Physics and Astronomy and Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, IN, 47907, USA.,Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
| | - R Kallaher
- Department of Physics and Astronomy and Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, IN, 47907, USA.,Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
| | - G C Gardner
- Department of Physics and Astronomy and Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, IN, 47907, USA.,Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy and Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, IN, 47907, USA.,Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA.,School of Materials Engineering, Purdue University, West Lafayette, IN, 47907, USA.,School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - C M Marcus
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen and Microsoft Quantum Lab Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark.
| | - F Nichele
- Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen and Microsoft Quantum Lab Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark. .,IBM Research - Zurich, Sumerstrasse 4, 8803, Rschlikon, Switzerland.
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9
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Nichele F, Portolés E, Fornieri A, Whiticar AM, Drachmann ACC, Gronin S, Wang T, Gardner GC, Thomas C, Hatke AT, Manfra MJ, Marcus CM. Relating Andreev Bound States and Supercurrents in Hybrid Josephson Junctions. Phys Rev Lett 2020; 124:226801. [PMID: 32567899 DOI: 10.1103/physrevlett.124.226801] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 03/03/2020] [Accepted: 04/27/2020] [Indexed: 06/11/2023]
Abstract
We demonstrate concomitant measurement of phase-dependent critical current and Andreev bound state spectrum in a highly transmissive InAs Josephson junction embedded in a dc superconducting quantum interference device (SQUID). Tunneling spectroscopy reveals Andreev bound states with near unity transmission probability. A nonsinusoidal current-phase relation is derived from the Andreev spectrum, showing excellent agreement with the one extracted from the SQUID critical current. Both measurements are reconciled within a short junction model where multiple Andreev bound states, with various transmission probabilities, contribute to the entire supercurrent flowing in the junction.
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Affiliation(s)
- F Nichele
- Center for Quantum Devices and Microsoft Quantum Lab-Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
- IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland
| | - E Portolés
- Center for Quantum Devices and Microsoft Quantum Lab-Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - A Fornieri
- Center for Quantum Devices and Microsoft Quantum Lab-Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - A M Whiticar
- Center for Quantum Devices and Microsoft Quantum Lab-Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - A C C Drachmann
- Center for Quantum Devices and Microsoft Quantum Lab-Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - S Gronin
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA
| | - T Wang
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA
| | - C Thomas
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - A T Hatke
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA
| | - C M Marcus
- Center for Quantum Devices and Microsoft Quantum Lab-Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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10
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Fu X, Shi Q, Zudov MA, Gardner GC, Watson JD, Manfra MJ, Baldwin KW, Pfeiffer LN, West KW. Anomalous Nematic States in High Half-Filled Landau Levels. Phys Rev Lett 2020; 124:067601. [PMID: 32109097 DOI: 10.1103/physrevlett.124.067601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2019] [Accepted: 01/22/2020] [Indexed: 06/10/2023]
Abstract
It is well established that the ground states of a two-dimensional electron gas with half-filled high (N≥2) Landau levels are compressible charge-ordered states, known as quantum Hall stripe (QHS) phases. The generic features of QHSs are a maximum (minimum) in a longitudinal resistance R_{xx} (R_{yy}) and a nonquantized Hall resistance R_{H}. Here, we report on emergent minima (maxima) in R_{xx} (R_{yy}) and plateaulike features in R_{H} in half-filled N≥3 Landau levels. Remarkably, these unexpected features develop at temperatures considerably lower than the onset temperature of QHSs, suggestive of a new ground state.
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Affiliation(s)
- X Fu
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Q Shi
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - M A Zudov
- School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - G C Gardner
- Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - J D Watson
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Microsoft Quantum Lab Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- Department of Physics and Astronomy, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering and School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - K W Baldwin
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - L N Pfeiffer
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - K W West
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
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11
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O'Farrell ECT, Drachmann ACC, Hell M, Fornieri A, Whiticar AM, Hansen EB, Gronin S, Gardner GC, Thomas C, Manfra MJ, Flensberg K, Marcus CM, Nichele F. Hybridization of Subgap States in One-Dimensional Superconductor-Semiconductor Coulomb Islands. Phys Rev Lett 2018; 121:256803. [PMID: 30608825 DOI: 10.1103/physrevlett.121.256803] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Indexed: 06/09/2023]
Abstract
We present measurements of one-dimensional superconductor-semiconductor Coulomb islands, fabricated by gate confinement of a two-dimensional InAs heterostructure with an epitaxial Al layer. When tuned via electrostatic side gates to regimes without subgap states, Coulomb blockade reveals Cooper-pair mediated transport. When subgap states are present, Coulomb peak positions and heights oscillate in a correlated way with magnetic field and gate voltage, as predicted theoretically, with (anti)crossings in (parallel) transverse magnetic field indicating Rashba-type spin-orbit coupling. Overall results are consistent with a picture of overlapping Majorana zero modes in finite wires.
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Affiliation(s)
- E C T O'Farrell
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - A C C Drachmann
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - M Hell
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
- Division of Solid State Physics and NanoLund, Lund University, Box 118, S-22100 Lund, Sweden
| | - A Fornieri
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - A M Whiticar
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - E B Hansen
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - S Gronin
- Department of Physics and Astronomy and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- Department of Physics and Astronomy and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - C Thomas
- Department of Physics and Astronomy and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - K Flensberg
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - C M Marcus
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - F Nichele
- Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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12
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Schreiber KA, Samkharadze N, Gardner GC, Lyanda-Geller Y, Manfra MJ, Pfeiffer LN, West KW, Csáthy GA. Electron-electron interactions and the paired-to-nematic quantum phase transition in the second Landau level. Nat Commun 2018; 9:2400. [PMID: 29921969 PMCID: PMC6008478 DOI: 10.1038/s41467-018-04879-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 05/23/2018] [Indexed: 11/12/2022] Open
Abstract
In spite of its ubiquity in strongly correlated systems, the competition of paired and nematic ground states remains poorly understood. Recently such a competition was reported in the two-dimensional electron gas at filling factor ν = 5/2. At this filling factor a pressure-induced quantum phase transition was observed from the paired fractional quantum Hall state to the quantum Hall nematic. Here we show that the pressure-induced paired-to-nematic transition also develops at ν = 7/2, demonstrating therefore this transition in both spin branches of the second orbital Landau level. However, we find that pressure is not the only parameter controlling this transition. Indeed, ground states consistent with those observed under pressure also develop in a sample measured at ambient pressure, but in which the electron-electron interaction was tuned close to its value at the quantum critical point. Our experiments suggest that electron-electron interactions play a critical role in driving the paired-to-nematic transition.
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Affiliation(s)
- K A Schreiber
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - N Samkharadze
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
- QuTech and Kavli Institute of NanoScience, Delft University of Technology, Lorentzweg 1, 2628 CJ, Delft, Netherlands
| | - G C Gardner
- School of Materials Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
| | - Y Lyanda-Geller
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, IN, 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN, 47907, USA
| | - L N Pfeiffer
- Department of Electrical Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - K W West
- Department of Electrical Engineering, Princeton University, Princeton, NJ, 08544, USA
| | - G A Csáthy
- Department of Physics and Astronomy, Purdue University, West Lafayette, IN, 47907, USA.
- Birck Nanotechnology Center, Purdue University, West Lafayette, IN, 47907, USA.
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13
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Rossokhaty AV, Baum Y, Folk JA, Watson JD, Gardner GC, Manfra MJ. Electron-Hole Asymmetric Chiral Breakdown of Reentrant Quantum Hall States. Phys Rev Lett 2016; 117:166805. [PMID: 27792394 DOI: 10.1103/physrevlett.117.166805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Indexed: 06/06/2023]
Abstract
Reentrant integer quantum Hall (RIQH) states are believed to be correlated electron solid phases, although their microscopic description remains unclear. As bias current increases, longitudinal and Hall resistivities measured for these states exhibit multiple sharp breakdown transitions, a signature unique to RIQH states. A comparison of RIQH breakdown characteristics at multiple voltage probes indicates that these signatures can be ascribed to a phase boundary between broken-down and unbroken regions, spreading chirally from source and drain contacts as a function of bias current and passing voltage probes one by one. The chiral sense of the spreading is not set by the chirality of the edge state itself, instead depending on electron- or holelike character of the RIQH state.
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Affiliation(s)
- A V Rossokhaty
- Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T1Z4, Canada
- Department of Radio Engineering and Cybernetics, Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia
| | - Y Baum
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - J A Folk
- Stewart Blusson Quantum Matter Institute, University of British Columbia, Vancouver, British Columbia V6T1Z4, Canada
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia V6T1Z4, Canada
| | - J D Watson
- Department of Physics and Astronomy, and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Department of Physics and Astronomy, and Station Q Purdue, Purdue University, West Lafayette, Indiana 47907, USA
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
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14
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Levy AL, Wurstbauer U, Kuznetsova YY, Pinczuk A, Pfeiffer LN, West KW, Manfra MJ, Gardner GC, Watson JD. Optical Emission Spectroscopy Study of Competing Phases of Electrons in the Second Landau Level. Phys Rev Lett 2016; 116:016801. [PMID: 26799037 DOI: 10.1103/physrevlett.116.016801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Indexed: 06/05/2023]
Abstract
Quantum phases of electrons in the filling factor range 2≤ν≤3 are probed by the weak optical emission from the partially populated second Landau level and spin wave measurements. Observations of optical emission include a multiplet of sharp peaks that exhibit a strong filling factor dependence. Spin wave measurements by resonant inelastic light scattering probe breaking of spin rotational invariance and are used to link this optical emission with collective phases of electrons. A remarkably rapid interplay between emission peak intensities manifests phase competition in the second Landau level.
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Affiliation(s)
- A L Levy
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - U Wurstbauer
- Walter Schottky Institut and Physik-Department, Technische Universität München, Am Coulombwall 4a, 85748 Garching, Germany
- Nanosystems Initiative Munich (NIM), Munich, Germany
| | - Y Y Kuznetsova
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - A Pinczuk
- Department of Physics, Columbia University, New York, New York 10027, USA
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, USA
| | - L N Pfeiffer
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - K W West
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - M J Manfra
- Department of Physics and Astronomy, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- School of Materials Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
- School of Electrical and Computer Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- School of Materials Engineering, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - J D Watson
- Department of Physics and Astronomy, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
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15
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Deng N, Gardner GC, Mondal S, Kleinbaum E, Manfra MJ, Csáthy GA. ν=5/2 fractional quantum Hall state in the presence of alloy disorder. Phys Rev Lett 2014; 112:116804. [PMID: 24702403 DOI: 10.1103/physrevlett.112.116804] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Indexed: 06/03/2023]
Abstract
We report quantitative measurements of the impact of alloy disorder on the ν = 5/2 fractional quantum Hall state. Alloy disorder is controlled by the aluminum content x in the Al(x)Ga(1-x)As channel of a quantum well. We find that the ν = 5/2 state is suppressed with alloy scattering. To our surprise, in samples with alloy disorder the ν = 5/2 state appears at significantly reduced mobilities when compared to samples in which alloy disorder is not the dominant scattering mechanism. Our results highlight the distinct roles of the different types of disorder present in these samples, such as the short-range alloy and the long-range Coulomb disorder.
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Affiliation(s)
- Nianpei Deng
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
| | - G C Gardner
- Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA and School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - S Mondal
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
| | - E Kleinbaum
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
| | - M J Manfra
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA and School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, USA and School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907, USA
| | - G A Csáthy
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA and Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA
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16
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Makowski MS, Kim S, Gaillard M, Janes D, Manfra MJ, Bryan I, Sitar Z, Arellano C, Xie J, Collazo R, Ivanisevic A. Physisorption of functionalized gold nanoparticles on AlGaN/GaN high electron mobility transistors for sensing applications. Appl Phys Lett 2013; 102:74102. [PMID: 23509411 PMCID: PMC3592857 DOI: 10.1063/1.4791788] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2012] [Accepted: 01/29/2013] [Indexed: 06/01/2023]
Abstract
AlGaN/GaN high electron mobility transistors (HEMTs) were used to measure electrical characteristics of physisorbed gold nanoparticles (Au NPs) functionalized with alkanethiols with a terminal methyl, amine, or carboxyl functional group. Additional alkanethiol was physisorbed onto the NP treated devices to distinguish between the effects of the Au NPs and alkanethiols on HEMT operation. Scanning Kelvin probe microscopy and electrical measurements were used to characterize the treatment effects. The HEMTs were operated near threshold voltage due to the greatest sensitivity in this region. The Au NP/HEMT system electrically detected functional group differences on adsorbed NPs which is pertinent to biosensor applications.
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Affiliation(s)
- M S Makowski
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, USA ; Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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17
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Deng N, Kumar A, Manfra MJ, Pfeiffer LN, West KW, Csáthy GA. Collective nature of the reentrant integer quantum Hall states in the second Landau level. Phys Rev Lett 2012; 108:086803. [PMID: 22463555 DOI: 10.1103/physrevlett.108.086803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Indexed: 05/31/2023]
Abstract
We report an unexpected sharp peak in the temperature dependence of the magnetoresistance of the reentrant integer quantum Hall states in the second Landau level. This peak defines the onset temperature of these states. We find that in different spin branches the onset temperatures of the reentrant states scale with the Coulomb energy. This scaling provides direct evidence that Coulomb interactions play an important role in the formation of these reentrant states evincing their collective nature.
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Affiliation(s)
- N Deng
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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18
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Samkharadze N, Kumar A, Manfra MJ, Pfeiffer LN, West KW, Csáthy GA. Integrated electronic transport and thermometry at milliKelvin temperatures and in strong magnetic fields. Rev Sci Instrum 2011; 82:053902. [PMID: 21639513 DOI: 10.1063/1.3586766] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We fabricated a He-3 immersion cell for transport measurements of semiconductor nanostructures at ultra low temperatures and in strong magnetic fields. We have a new scheme of field-independent thermometry based on quartz tuning fork Helium-3 viscometry which monitors the local temperature of the sample's environment in real time. The operation and measurement circuitry of the quartz viscometer is described in detail. We provide evidence that the temperature of two-dimensional electron gas confined to a GaAs quantum well follows the temperature of the quartz viscometer down to 4 mK.
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Affiliation(s)
- N Samkharadze
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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19
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Diagne MA, Greszik M, Duerr EK, Zayhowski JJ, Manfra MJ, Bailey RJ, Donnelly JP, Turner GW. Integrated array of 2-μm antimonide-based single-photon counting devices. Opt Express 2011; 19:4210-4216. [PMID: 21369250 DOI: 10.1364/oe.19.004210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A 32x32 Sb-based Geiger-mode (GM) avalanche photodiode array, operating at 2 μm with three-dimensional imaging capability, is presented. The array is interfaced with a ROIC (readout integrated circuit) in which each pixel can detect a photon and record the arrival time. The hybridized unit for the 1000-element focal plane array, when operated at 77K with 1 V overbias range, shows an average dark count rate of 1.5 kHz. Three-dimensional range images of objects were acquired.
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Affiliation(s)
- M A Diagne
- Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, Massachusetts 02420-9108, USA.
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20
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Kumar A, Csáthy GA, Manfra MJ, Pfeiffer LN, West KW. Nonconventional odd-denominator fractional quantum Hall states in the second Landau level. Phys Rev Lett 2010; 105:246808. [PMID: 21231551 DOI: 10.1103/physrevlett.105.246808] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Indexed: 05/30/2023]
Abstract
We report the observation of a new fractional quantum Hall state in the second Landau level of a two-dimensional electron gas at the Landau level filling factor ν=2+6/13. We find that the model of noninteracting composite fermions can explain the magnitude of gaps of the prominent 2+1/3 and 2+2/3 states. The same model fails, however, to account for the gaps of the 2+2/5 and the newly observed 2+6/13 states suggesting that these two states are of exotic origin.
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Affiliation(s)
- A Kumar
- Department of Physics, Purdue University, West Lafayette, Indiana 47907, USA
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21
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Manfra MJ, Hwang EH, Das Sarma S, Pfeiffer LN, West KW, Sergent AM. Transport and percolation in a low-density high-mobility two-dimensional hole system. Phys Rev Lett 2007; 99:236402. [PMID: 18233387 DOI: 10.1103/physrevlett.99.236402] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2007] [Indexed: 05/25/2023]
Abstract
We present a study of the temperature and density dependence of the resistivity of an extremely high quality two-dimensional hole system grown on the (100) surface of GaAs. For high densities in the metallic regime (p > or approximately4x10;{9} cm;{-2}), the nonmonotonic temperature dependence ( approximately 50-300 mK) of the resistivity is consistent with temperature dependent screening of residual impurities. At a fixed temperature of T=50 mK, the conductivity versus density data indicate an inhomogeneity driven percolation-type transition to an insulating state at a critical density of 3.8x10;{9} cm;{-2}.
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Affiliation(s)
- M J Manfra
- Bell Laboratories, Alcatel-Lucent, Murray Hill, New Jersey 07974, USA
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22
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Manfra MJ, de Picciotto R, Jiang Z, Simon SH, Pfeiffer LN, West KW, Sergent AM. Impact of spin-orbit coupling on quantum Hall nematic phases. Phys Rev Lett 2007; 98:206804. [PMID: 17677728 DOI: 10.1103/physrevlett.98.206804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Indexed: 05/16/2023]
Abstract
Anisotropic charge transport is observed in a two-dimensional (2D) hole system in a perpendicular magnetic field at filling factors nu=7/2, nu=11/2, and nu=13/2 at low temperature. In stark contrast, the transport at nu=9/2 is isotropic for all temperatures. Isotropic hole transport at nu=7/2 is restored for sufficiently low 2D densities or an asymmetric confining potential. The density and symmetry dependences of the observed anisotropies suggest that strong spin-orbit coupling in the hole system contributes to the unusual transport behavior.
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Affiliation(s)
- M J Manfra
- Bell Laboratories, Alcatel-Lucent, Murray Hill, New Jersey 07974, USA
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23
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Manfra MJ, Weimann NG, Mitrofanov O, Waechtler T, Tennant DM. High power GaN/AlGaN/GaN HEMTs operating at 2 to 25 GHz grown by plasma-assisted MBE. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/pssa.200303277] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Manfra MJ, Aifer EH, Goldberg BB, Broido DA, Pfeiffer L, West K. Temperature dependence of the spin polarization of a quantum Hall ferromagnet. Phys Rev B Condens Matter 1996; 54:R17327-R17330. [PMID: 9985949 DOI: 10.1103/physrevb.54.r17327] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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