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Spin effect on the low-temperature resistivity maximum in a strongly interacting 2D electron system. Sci Rep 2022; 12:5080. [PMID: 35332223 PMCID: PMC8948273 DOI: 10.1038/s41598-022-09034-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 03/16/2022] [Indexed: 11/08/2022] Open
Abstract
The increase in the resistivity with decreasing temperature followed by a drop by more than one order of magnitude is observed on the metallic side near the zero-magnetic-field metal-insulator transition in a strongly interacting two-dimensional electron system in ultra-clean SiGe/Si/SiGe quantum wells. We find that the temperature [Formula: see text], at which the resistivity exhibits a maximum, is close to the renormalized Fermi temperature. However, rather than increasing along with the Fermi temperature, the value [Formula: see text] decreases appreciably for spinless electrons in spin-polarizing (parallel) magnetic fields. The observed behaviour of [Formula: see text] cannot be described by existing theories. The results indicate the spin-related origin of the effect.
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2
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Asakawa Y, Masubuchi S, Inoue N, Morikawa S, Watanabe K, Taniguchi T, Machida T. Intersubband Landau Level Couplings Induced by In-Plane Magnetic Fields in Trilayer Graphene. PHYSICAL REVIEW LETTERS 2017; 119:186802. [PMID: 29219586 DOI: 10.1103/physrevlett.119.186802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Indexed: 06/07/2023]
Abstract
We observed broken-symmetry quantum Hall effects and level crossings between spin- and valley- resolved Landau levels (LLs) in Bernal stacked trilayer graphene. When the magnetic field was tilted with respect to the sample normal from 0° to 66°, the LL crossings formed at intersections of zeroth and second LLs from monolayer-graphene-like and bilayer-graphene-like subbands, respectively, exhibited a sequence of transitions. The results indicate the LLs from different subbands are coupled by in-plane magnetic fields (B_{∥}), which was explained by developing the tight-binding model Hamiltonian of trilayer graphene under B_{∥}.
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Affiliation(s)
- Yuta Asakawa
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Satoru Masubuchi
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Naoko Inoue
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Sei Morikawa
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Kenji Watanabe
- Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- Advanced Materials Laboratory, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Tomoki Machida
- Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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3
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Wen J, Zhang X, Gao H. Intrinsic non-ohmic electronic transport properties of the transparent In-Zn-O compound nanobelts under ohmic contact and out of the space charge limited transport region. NANOTECHNOLOGY 2016; 27:075703. [PMID: 26763412 DOI: 10.1088/0957-4484/27/7/075703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
It is generally accepted that the nonlinear I-V characteristics for semiconductor nanostructures are mainly induced by the Schottky contacts or by the space charge limited transport mechanism. We perform I-V measurements on undoped and doped In-Zn-O compound nanobelts and confirm that their intrinsic non-ohmic transport behaviors are not caused by these mechanisms. A model based on the hopping assisted trap state electrons transport process is introduced to explain the nonlinear I-V characteristics and to extract their electrical parameters. An understanding of this trap-state influenced carrier transport can advance the progress of nanomaterials applications and enable us to distinguish their intrinsic transport behaviors from contact effects. The results also indicate that the material has good electrical properties and can be used as a potential substitute for In2O3.
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Affiliation(s)
- Jing Wen
- Department of Physics, Harbin Institute of Technology, Harbin 150001, People's Republic of China
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4
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Zhou X, Schmidt B, Proust C, Gervais G, Pfeiffer LN, West KW, Sarma SD. Quantum-classical crossover and apparent metal-insulator transition in a weakly interacting 2D Fermi liquid. PHYSICAL REVIEW LETTERS 2011; 107:086804. [PMID: 21929191 DOI: 10.1103/physrevlett.107.086804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2011] [Indexed: 05/31/2023]
Abstract
We report the observation of an apparent parallel magnetic-field-induced metal-insulator transition in a high-mobility two-dimensional electron gas for which spin and localization physics most likely play no major role. The high-mobility metallic phase at low field is consistent with the established Fermi liquid transport theory including phonon scattering, whereas the phase at higher field shows a large insulatinglike negative temperature dependence at resistances much smaller than the quantum of resistance h/e(2). We argue that this observation is a direct manifestation of a quantum-classical crossover arising predominantly from the magneto-orbital coupling between the finite width of the two-dimensional electron gas and the in-plane magnetic field.
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Affiliation(s)
- Xiaoqing Zhou
- Department of Physics, McGill University, Montreal, H3A 2T8, Canada
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5
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Zhou X, Piot BA, Bonin M, Engel LW, Das Sarma S, Gervais G, Pfeiffer LN, West KW. Colossal magnetoresistance in an ultraclean weakly interacting 2D Fermi liquid. PHYSICAL REVIEW LETTERS 2010; 104:216801. [PMID: 20867126 DOI: 10.1103/physrevlett.104.216801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Indexed: 05/29/2023]
Abstract
We report the observation of a new phenomenon of colossal magnetoresistance in a 40 nm wide GaAs quantum well in the presence of an external magnetic field applied parallel to the high-mobility 2D electron layer. In a strong magnetic field, the magnetoresistance is observed to increase by a factor of ∼300 from 0 to 45 T without the system undergoing any metal-insulator transition. We discuss how this colossal magnetoresistance effect cannot be attributed to the spin degree of freedom or localization physics, but most likely emanates from strong magneto-orbital coupling between the two-dimensional electron gas and the magnetic field. Our observation is consistent with a field-induced 2D-to-3D transition in the confined electronic system.
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Affiliation(s)
- Xiaoqing Zhou
- Department of Physics, McGill University, Montreal, H3A 2T8, Canada
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6
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Pillarisetty R, Noh H, Tutuc E, Poortere EPD, Tsui DC, Shayegan M. Spin polarization dependence of the coulomb drag at large r(s). PHYSICAL REVIEW LETTERS 2005; 94:016807. [PMID: 15698117 DOI: 10.1103/physrevlett.94.016807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2004] [Indexed: 05/24/2023]
Abstract
We find that the temperature dependence of the drag resistivity between two dilute two-dimensional hole systems exhibits an unusual dependence upon spin polarization. Our main observation is that near the apparent metal-insulator transition, the temperature dependence of the drag, given by Talpha, weakens significantly with the application of a parallel magnetic field (B(||)), with alpha saturating at half its zero field value for B(||)>B(*), where B(*) is the polarization field.
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Affiliation(s)
- R Pillarisetty
- Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA
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7
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Hilke M. Noninteracting electrons and the metal-insulator transition in two dimensions with correlated impurities. PHYSICAL REVIEW LETTERS 2003; 91:226403. [PMID: 14683259 DOI: 10.1103/physrevlett.91.226403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2003] [Indexed: 05/24/2023]
Abstract
While standard scaling arguments show that a system of noninteracting electrons in two dimensions and in the presence of uncorrelated disorder is insulating, in this paper we discuss the case where interimpurity correlations are included. We find that for pointlike impurities and an infinite interimpurity correlation length, a mobility edge exists in 2D even if the individual impurity potentials are random. In the uncorrelated system we recover the scaling results, while in the intermediate regime for length scales comparable to the correlation length, the system behaves like a metal but with increasing fluctuations, before strong localization eventually takes over for length scales much larger than the correlation length. In the intermediate regime, the relevant length scale is given by the interimpurity correlation length, with important consequences for high mobility systems.
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Affiliation(s)
- M Hilke
- Department of Physics, McGill University, Montréal, Quebec, Canada H3A 2T8.
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8
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Denteneer PJH, Scalettar RT. Interacting electrons in a two-dimensional disordered environment: effect of a zeeman magnetic field. PHYSICAL REVIEW LETTERS 2003; 90:246401. [PMID: 12857206 DOI: 10.1103/physrevlett.90.246401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2003] [Indexed: 05/24/2023]
Abstract
The effect of a Zeeman magnetic field coupled to the spin of the electrons on the conducting properties of the disordered Hubbard model is studied. Using the determinant quantum Monte Carlo method, the temperature- and magnetic-field-dependent conductivity is calculated, as well as the degree of spin polarization. We find that the Zeeman magnetic field suppresses the metallic behavior present for certain values of interaction and disorder strength and is able to induce a metal-insulator transition at a critical field strength. It is argued that the qualitative features of magnetoconductance in this microscopic model containing both repulsive interactions and disorder are in agreement with experimental findings in two-dimensional electron and hole gases in semiconductor structures.
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Affiliation(s)
- P J H Denteneer
- Lorentz Institute, Leiden University, PO Box 9506, 2300 RA Leiden, The Netherlands
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9
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Pillarisetty R, Noh H, Tutuc E, De Poortere EP, Tsui DC, Shayegan M. In-plane magnetodrag between dilute two-dimensional systems. PHYSICAL REVIEW LETTERS 2003; 90:226801. [PMID: 12857330 DOI: 10.1103/physrevlett.90.226801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2003] [Indexed: 05/24/2023]
Abstract
We performed in-plane magnetodrag measurements on dilute double layer two-dimensional hole systems, at in-plane magnetic fields that suppress the apparent metallic behavior, and to fields well above those required to fully spin polarize the system. When compared to the single layer magnetoresistance, the magnetodrag exhibits exactly the same qualitative behavior. In addition, we have found that the enhancement to the drag from the in-plane field exhibits a strong maximum when both layer densities are matched.
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Affiliation(s)
- R Pillarisetty
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
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10
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Proskuryakov YY, Savchenko AK, Safonov SS, Pepper M, Simmons MY, Ritchie DA. Hole-hole interaction effect in the conductance of the two-dimensional hole gas in the ballistic regime. PHYSICAL REVIEW LETTERS 2002; 89:076406. [PMID: 12190541 DOI: 10.1103/physrevlett.89.076406] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2001] [Indexed: 05/23/2023]
Abstract
On a high-mobility two-dimensional hole gas (2DHG) in a GaAs/GaAlAs heterostructure we study the interaction correction to the Drude conductivity in the ballistic regime, k(B)Ttau/ variant Planck's over 2pi >1. It is shown that the "metallic" behavior of the resistivity (drho/dT>0) of the low-density 2DHG is caused by the hole-hole interaction effect in this regime. We find that the temperature dependence of the conductivity and the parallel-field magnetoresistance are in agreement with this description, and determine the Fermi-liquid interaction constant Fsigma0 which controls the sign of drho/dT.
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Affiliation(s)
- Y Y Proskuryakov
- School of Physics, University of Exeter, Stocker Road, United Kingdom
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11
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Gao XPA, Mills AP, Ramirez AP, Pfeiffer LN, West KW. Weak-localization-like temperature-dependent conductivity of a dilute two-dimensional hole gas in a parallel magnetic field. PHYSICAL REVIEW LETTERS 2002; 89:016801. [PMID: 12097059 DOI: 10.1103/physrevlett.89.016801] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2001] [Indexed: 05/23/2023]
Abstract
We have studied the magnetotransport properties of a high mobility two-dimensional hole gas (2DHG) in a 10 nm GaAs quantum well with densities in the range of (0.7-1.6) x 10(10) cm(-2) on the metallic side of the zero-field "metal-insulator transition." In a parallel field well above B(c) that suppresses the metallic conductivity, the 2DHG exhibits a conductivity Delta(g)(T) approximately (1/pi) (e(2)/h)lnT reminiscent of weak localization for Fermi liquids. The experiments are consistent with the coexistence of two phases in our system: a metallic phase and a weakly insulating Fermi liquid phase.
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Affiliation(s)
- Xuan P A Gao
- Department of Applied Physics & Applied Math, Columbia University, New York City, New York 10027, USA
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12
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Gao XPA, Mills AP, Ramirez AP, Pfeiffer LN, West KW. Two-dimensional metal in a parallel magnetic field. PHYSICAL REVIEW LETTERS 2002; 88:166803. [PMID: 11955247 DOI: 10.1103/physrevlett.88.166803] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2001] [Indexed: 05/23/2023]
Abstract
We have investigated the effect of an in-plane parallel magnetic field (B(axially) on two high mobility metallic-like dilute two-dimensional hole gas systems in GaAs quantum wells. The experiments reveal that, while suppressing the magnitude of the low temperature resistance drop, B(axially) does not affect E(a), the characteristic energy scale of the metallic resistance drop. The field B(c) at which the metallic-like resistance drop vanishes is dependent on both the width of the quantum well and the orientation of B(axially). It is unexpected that E(a) is unaffected by B(axially) up to B(c) despite the fact that the Zeeman energy at B(c) is roughly equal to E(a).
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Affiliation(s)
- Xuan P A Gao
- Bell Laboratories, Lucent Technologies, Murray Hill, New Jersey 07974, USA
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13
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Eng K, Feng XG, Popović D, Washburn S. Effects of a parallel magnetic field on the metal-insulator transition in a dilute two-dimensional electron system. PHYSICAL REVIEW LETTERS 2002; 88:136402. [PMID: 11955112 DOI: 10.1103/physrevlett.88.136402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2001] [Indexed: 05/23/2023]
Abstract
The temperature dependence of conductivity sigma(T) of a two-dimensional electron system in silicon has been studied in parallel magnetic fields B. At B = 0, the system displays a metal-insulator transition at a critical electron density n(c)(0), and dsigma/dT>0 in the metallic phase. At low fields ( B < or approximately equal to 2 T), n(c) increases as n(c)(B)-n(c)(0) proportional, variant Bbeta ( beta approximately 1), and the zero-temperature conductivity scales as sigma(n(s),B,T = 0)/sigma(n(s),0,0) = f(B(beta)/delta(n)), where delta(n) = [n(s)-n(c)(0)]/n(c)(0) and n(s) is electron density, as expected for a quantum phase transition. The metallic phase persists in fields of up to 18 T, consistent with the saturation of n(c) at high fields.
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Affiliation(s)
- Kevin Eng
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
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14
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Pudalov VM, Brunthaler G, Prinz A, Bauer G. Weak anisotropy and disorder dependence of the in-plane magnetoresistance in high-mobility (100) Si-inversion layers. PHYSICAL REVIEW LETTERS 2002; 88:076401. [PMID: 11863922 DOI: 10.1103/physrevlett.88.076401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2000] [Revised: 07/06/2001] [Indexed: 05/23/2023]
Abstract
We report studies of the magnetoresistance (MR) in a two-dimensional electron system in (100) Si-inversion layers, for perpendicular and parallel orientations of the current with respect to the magnetic field in the 2D plane. The magnetoresistance is almost isotropic; this result does not support the suggestion of its orbital origin. In the hopping regime, however, the MR contains a weak anisotropic component that is nonmonotonic in the magnetic field. We found that the field, at which the MR saturates, varies for different samples by a factor of 2 at a given carrier density. Therefore, the saturation of the MR cannot be identified with the complete spin polarization of free carriers.
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Affiliation(s)
- V M Pudalov
- P. N. Lebedev Physics Institute, 119991 Moscow, Russia
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15
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Tutuc E, Melinte S, Shayegan M. Spin polarization and g factor of a dilute GaAs two-dimensional electron system. PHYSICAL REVIEW LETTERS 2002; 88:036805. [PMID: 11801080 DOI: 10.1103/physrevlett.88.036805] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2001] [Indexed: 05/23/2023]
Abstract
The effective g factor (g(*)) of a dilute interacting two-dimensional electron system is expected to increase with respect to its bare value as the density is lowered, and to eventually diverge as the system makes a transition to a ferromagnetic state. We report here measurements of g(*) in dilute (density 0.8 to 6.5x10(10) cm(-2)), high-mobility GaAs two-dimensional electrons from their spin polarization in a parallel magnetic field. The data reveal a surprising trend. While g(*) is indeed significantly enhanced with respect to the band g factor of GaAs, the enhancement factor decreases from about 6 to 3 as the density is reduced.
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Affiliation(s)
- E Tutuc
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
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16
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Tutuc E, De Poortere EP, Papadakis SJ, Shayegan M. In-plane magnetic field-induced spin polarization and transition to insulating behavior in two-dimensional hole systems. PHYSICAL REVIEW LETTERS 2001; 86:2858-2861. [PMID: 11290057 DOI: 10.1103/physrevlett.86.2858] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2000] [Indexed: 05/23/2023]
Abstract
Using a novel technique, we make quantitative measurements of the spin polarization of dilute [ (3.4-6.8)x10(10) cm(-2)] GaAs (311)A two-dimensional holes as a function of an in-plane magnetic field. As the field is increased the system gradually becomes spin polarized, with the degree of spin polarization depending on the orientation of the field relative to the crystal axes. Moreover, the behavior of the system turns from metallic to insulating before it is fully spin polarized. The minority-spin population at the transition is approximately 8x10(9) cm(-2), close to the density below which the system makes a transition to an insulating state in the absence of a magnetic field.
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Affiliation(s)
- E Tutuc
- Department of Electrical Engineering, Princeton University, Princeton, NJ 08544, USA
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17
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Chamon C, Mucciolo ER. Nonperturbative saddle point for the effective action of disordered and interacting electrons in 2D. PHYSICAL REVIEW LETTERS 2000; 85:5607-5610. [PMID: 11136058 DOI: 10.1103/physrevlett.85.5607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2000] [Indexed: 05/23/2023]
Abstract
We find a nonperturbative saddle-point solution for the nonlinear sigma model proposed by Finkelstein for interacting and disordered electronic systems. Spin rotation symmetry, present in the original saddle-point solution, is spontaneously broken at one loop, as in the Coleman-Weinberg mechanism. The new solution is singular in both the disorder and triplet interaction strengths, and it also explicitly demonstrates that a nontrivial ferromagnetic state appears in a theory where the disorder average is carried out from the outset.
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Affiliation(s)
- C Chamon
- Department of Physics, Boston University, Boston, Massachusetts, USA
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18
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Papadakis SJ, Shayegan M, Winkler R. Anisotropic magnetoresistance of two-dimensional holes in GaAs. PHYSICAL REVIEW LETTERS 2000; 84:5592-5595. [PMID: 10991002 DOI: 10.1103/physrevlett.84.5592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/1999] [Indexed: 05/23/2023]
Abstract
Experiments on high-quality GaAs (311)A two-dimensional holes at low temperatures reveal a remarkable dependence of the magnetoresistance, measured with an in-plane magnetic field ( B), on the direction of B relative to both the crystal axes and the current direction. The magnetoresistance features, and in particular the value of B above which the resistivity exhibits an insulating behavior, depend on the orientation of B. To explain the data, the anisotropic band structure of the holes and a repopulation of the spin subbands in the presence of B, as well as the coupling of the orbital motion to B, need to be taken into account.
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Affiliation(s)
- SJ Papadakis
- Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544, USA
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