Density dependence of valley polarization energy for composite fermions

被引：33
作者：
Padmanabhan, Medini [1 ]
Gokmen, T. [1 ]
Shayegan, M. [1 ]
机构：
[1] Princeton Univ, Dept Elect Engn, Princeton, NJ 08544 USA
来源：
PHYSICAL REVIEW B | 2009年 / 80卷 / 03期
关键词：
ELECTRON-SPIN POLARIZATION; PHASE-DIAGRAM; TRANSITION; NU=1/2; SYSTEM; NU=2/3;
D O I：
10.1103/PhysRevB.80.035423
中图分类号：
T [工业技术];
学科分类号：
08 ;
摘要：
In two-dimensional electron systems confined to wide AlAs quantum wells, composite fermions around the filling factor nu = 3/2 are fully spin polarized but possess a valley degree of freedom. Here we measure the energy needed to completely valley polarize these composite fermions as a function of electron density. Comparing our results to the existing theory, we find overall good quantitative agreement but there is an unexpected trend: the measured composite fermion valley polarization energy, normalized to the Coulomb energy, decreases with decreasing density.
引用
收藏
页数：5
相关论文
共 25 条
  • [1] Valley polarization and susceptibility of composite fermions around a filling factor v = 3/2
    Bishop, N. C.
    Padmanabhan, M.
    Vakili, K.
    Shkolnikov, Y. P.
    De Poortere, E. P.
    Shayegan, M.
    [J]. PHYSICAL REVIEW LETTERS, 2007, 98 (26)
  • [2] Measurements of composite fermion masses from the spin polarization of two-dimensional electrons in the region 1<ν<2 -: art. no. 161305
    Chughtai, R
    Zhitomirsky, V
    Nicholas, RJ
    Henini, M
    [J]. PHYSICAL REVIEW B, 2002, 65 (16): : 1 - 4
  • [3] Optically pumped NMR studies of electron spin polarization and dynamics:: New constraints on the composite fermion description of ν=1/2
    Dementyev, AE
    Kuzma, NN
    Khandelwal, P
    Barrett, SE
    Pfeiffer, LN
    West, KW
    [J]. PHYSICAL REVIEW LETTERS, 1999, 83 (24) : 5074 - 5077
  • [4] FRACTIONAL QUANTUM HALL-EFFECT AROUND NU=3/2 - COMPOSITE FERMIONS WITH A SPIN
    DU, RR
    YEH, AS
    STORMER, HL
    TSUI, DC
    PFEIFFER, LN
    WEST, KW
    [J]. PHYSICAL REVIEW LETTERS, 1995, 75 (21) : 3926 - 3929
  • [5] g factor of composite fermions around nu=2/3 from angular-dependent activation-energy measurements
    Du, RR
    Yeh, AS
    Stormer, HL
    Tsui, DC
    Pfeiffer, LN
    West, KW
    [J]. PHYSICAL REVIEW B, 1997, 55 (12) : R7351 - R7354
  • [6] EVIDENCE FOR A SPIN TRANSITION IN THE V=2/3 FRACTIONAL QUANTUM HALL-EFFECT
    EISENSTEIN, JP
    STORMER, HL
    PFEIFFER, LN
    WEST, KW
    [J]. PHYSICAL REVIEW B, 1990, 41 (11): : 7910 - 7913
  • [7] EVIDENCE FOR A PHASE-TRANSITION IN THE FRACTIONAL QUANTUM HALL-EFFECT
    EISENSTEIN, JP
    STORMER, HL
    PFEIFFER, L
    WEST, KW
    [J]. PHYSICAL REVIEW LETTERS, 1989, 62 (13) : 1540 - 1543
  • [8] FRACTIONAL QUANTUM HALL-EFFECT AT NU=2/3 AND NU=3/5 IN TILTED MAGNETIC-FIELDS
    ENGEL, LW
    HWANG, SW
    SAJOTO, T
    TSUI, DC
    SHAYEGAN, M
    [J]. PHYSICAL REVIEW B, 1992, 45 (07): : 3418 - 3425
  • [9] NMR investigation of how free composite fermions are at ν=1/2 -: art. no. 246804
    Freytag, N
    Horvatic, M
    Berthier, C
    Shayegan, M
    Lévy, LP
    [J]. PHYSICAL REVIEW LETTERS, 2002, 89 (24)
  • [10] Spin-valley phase diagram of the two-dimensional metal-insulator transition
    Gunawan, O.
    Gokmen, T.
    Vakili, K.
    Padmanabhan, M.
    De Poortere, E. P.
    Shayegan, M.
    [J]. NATURE PHYSICS, 2007, 3 (06) : 388 - 391
123