Absorption in the fractional quantum Hall regime: trion dichroism and spin polarization

Abstract

We present measurements of optical interband absorption in the fractional quantum Hall regime in a GaAs quantum well in the range 0 < nu < 1. We investigate the mechanism of singlet trion absorption, and show that its circular dichroism can be used as a probe of the spin polarization of the ground state of the two-dimensional electron system (2DES). We find that at nu = 1/3 the 2DES is fully spin-polarized. Increasing the filling factor results in a gradual depolarization, with a sharp minimum in the dichroism near nu = 2/3. We find that in the range 0.5 < nu < 0.85 the 2DES remains partially polarized for the broad range of magnetic fields from 2.75 to 11 Tesla. This is consistent with the presence of a mixture of polarized and depolarized regions.

arXiv comment4 pages, 4 figures (Fig 4 is in color)

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• Spin-pairing instabilities at the coincidence of two Landau levels
• Measurements of the Composite Fermion masses from the spin polarization of 2-D electrons in the region $1<\nu <2$

Cited by in corpus (16)

• Optical manipulation of the exciton charge state in single layer tungsten disulfide
• Quantum Hall Effect of Two-Component Bosons at Fractional and Integral Fillings
• Spinful Composite Fermions in a Negative Effective Field
• Polaron-Polaritons in the Integer and Fractional Quantum Hall Regimes
• Nonlinear optics in the fractional quantum Hall regime
• Enigmatic 4/11 State: A Prototype for Unconventional Fractional Quantum Hall Effect
• Luttinger liquid of trimers in Fermi gases with unequal masses
• Optical absorption to probe the quantum Hall ferromagnet at filling factor $\nu =1$
• Spin-Polarization of Composite Fermions and Particle-Hole Symmetry Breaking
• Extra Spin-Wave mode in Quantum Hall systems. Beyond the Skyrmion Limit
• Spin-texture and magneto-roton excitations at nu=1/3
• Possible realization of a chiral p-wave paired state in a two component system
• Phase diagram of the Two-Component Fractional Quantum Hall Effect
• Optical excitations in compressible and incompressible two-dimensional electron liquids
• Spin transition in the fractional quantum Hall regime: Effect of extent of the wave function
• Fermionic trimers in spin-dependent optical lattices