Quantum Lifetime in Ultra-High Quality GaAs Quantum Wells: Relationship to $\Delta_{5/2}$ and Impact of Density Fluctuations
Phys. Rev. B 96, 035309 (2017) We consider quantum lifetime derived from low-field Shubnikov-de Haas oscillations as a metric of quality of the two-dimensional electron gas in GaAs quantum wells that expresses large excitation gaps in the fractional quantum Hall states of the N=1 Landau level. Analy...
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Main Authors | , , , , , , , , |
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Format | Journal Article |
Language | English |
Published |
20.04.2017
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Subjects | |
Online Access | Get full text |
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Summary: | Phys. Rev. B 96, 035309 (2017) We consider quantum lifetime derived from low-field Shubnikov-de Haas
oscillations as a metric of quality of the two-dimensional electron gas in GaAs
quantum wells that expresses large excitation gaps in the fractional quantum
Hall states of the N=1 Landau level. Analysis indicates two salient features:
1) small density inhomogeneities dramatically impact the amplitude of
Shubnikov-de Haas oscillations such that the canonical method (cf. Coleridge,
Phys. Rev. B \textbf{44}, 3793) for determination of quantum lifetime
substantially underestimates $\tau_q$ unless density inhomogeneity is
explicitly considered; 2) $\tau_q$ does not correlate well with quality as
measured by $\Delta_{5/2}$, the excitation gap of the fractional quantum Hall
state at 5/2 filling. |
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DOI: | 10.48550/arxiv.1704.06213 |