Dependence of persistent gaps at Landau level crossings on relative spin

Abstract

We report measurements of the quantum Hall state energy gap at avoided crossings between Landau levels originating from different conduction band valleys in AlAs quantum wells. These gaps exhibit an approximately linear dependence on magnetic field over a wide range of fields and filling factors. More remarkably, we observe an unexpected dependence of the gap size on the relative spin orientation of the crossing levels, with parallel-spin crossings exhibiting larger gaps than antiparallel-spin crossings.

arXiv comment4 pages, 3 figures, submitted for publication

References in corpus (8)

• Valley splitting of AlAs two-dimensional electrons in a perpendicular magnetic field
• Pseudospin Anisotropy Classification of Quantum Hall Ferromagnets
• Low-temperature, in situ tunable, uniaxial stress measurements in semiconductors using a piezoelectric actuator
• Observation of Quantum Hall Valley Skyrmions
• Strong enhancement of the valley splitting in a 2D electron system in silicon
• Spin Transition in Strongly Correlated Bilayer Two Dimensional Electron Systems
• Dependence of spin susceptibility of a two-dimensional electron system on the valley degree of freedom
• Observation of Inter-Valley Gap Anomaly of Two Dimensional electrons in Silicon

Cited by in corpus (5)

• Spin susceptibility and effective mass of two-dimensional electrons in MgxZn1-xO/ZnO heterostructures
• When are the $q/3$ fractional quantum Hall states stable?
• Robust Quantum Hall Ferromagnetism near a Gate-Tuned ν = 1 Landau Level Crossing
• Probing Quantum Hall Pseudospin Ferromagnet by Resistively Detected NMR
• Observation of an in-plane magnetic-field-driven phase transition in a quantum Hall system with SU(4) symmetry