Role of Strain on the Coherent Properties of GaAs Excitons and Biexcitons

Abstract

Polarization-dependent two-dimensional Fourier-transform spectroscopy (2DFTS) is performed on excitons in strained bulk GaAs layers probing the coherent response for differing amounts of strain. Biaxial tensile strain lifts the degeneracy of heavy-hole (HH) and light-hole (LH) valence states, leading to an observed splitting of the associated excitons at low temperature. Increasing the strain increases the magnitude of the HH/LH exciton peak splitting, induces an asymmetry in the off-diagonal coherences, increases the difference in the HH and LH exciton homogenous linewidths, and increases the inhomogeneous broadening of both exciton species. All results arise from strain-induced variations in the local electronic environment, which is not uniform along the growth direction of the thin layers. For cross-linear polarized excitation, wherein excitonic signals give way to biexcitonic signals, the high-strain sample shows evidence of bound LH, HH, and mixed biexcitons.

10 pages, 4 figures, 2 tables, journal article

References in corpus (4)

• Two-dimensional correlation spectroscopy of two-exciton resonances in semiconductor quantum wells
• Coherent Excitonic Coupling in an Asymmetric Double InGaAs Quantum Well Arises from Many-Body Effects
• Multidimensional Coherent Spectroscopy of a Semiconductor Microcavity
• Mechanical control of spin-orbit splitting in GaAs and InGaAs epilayers

Cited by in corpus (5)

• Reconstruction of Bloch wavefunctions of holes in a semiconductor
• Temperature-dependent photoluminescence in Ge: experiment and theory
• Signatures of four-particle correlations associated with exciton-carrier interactions in coherent spectroscopy on bulk GaAs
• Diagonal Slice Four-Wave Mixing: Natural Separation of Coherent Broadening Mechanisms
• High-speed hyperspectral four-wave-mixing microscopy with frequency combs