Ultrafast Coulomb-induced dynamics of 2D magnetoexcitons

Abstract

We study theoretically the ultrafast nonlinear optical response of quantum well excitons in a perpendicular magnetic field. We show that for magnetoexcitons confined to the lowest Landau levels, the third-order four-wave-mixing (FWM) polarization is dominated by the exciton-exciton interaction effects. For repulsive interactions, we identify two regimes in the time-evolution of the optical polarization characterized by exponential and {\em power law} decay of the FWM signal. We describe these regimes by deriving an analytical solution for the memory kernel of the two-exciton wave-function in strong magnetic field. For strong exciton-exciton interactions, the decay of the FWM signal is governed by an antibound resonance with an interaction-dependent decay rate. For weak interactions, the continuum of exciton-exciton scattering states leads to a long tail of the time-integrated FWM signal for negative time delays, which is described by the product of a power law and a logarithmic factor. By combining this analytic solution with numerical calculations, we study the crossover between the exponential and non-exponential regimes as a function of magnetic field. For attractive exciton-exciton interaction, we show that the time-evolution of the FWM signal is dominated by the biexcitonic effects.

41 pages with 11 figs

References in corpus (4)

• Electronic Dephasing in the Quantum Hall Regime
• Coherent Ultrafast Optical Dynamics of the Fermi Edge Singularity
• Collective oscillations driven by correlation in the nonlinear optical regime
• Femtosecond Coherent Dynamics of the Fermi Edge Singularity and Exciton Hybrid

Cited by in corpus (8)

• Ultrafast Nonlinear Optical Response of Strongly Correlated Systems: Dynamics in the Quantum Hall Effect Regime
• Lightwave Terahertz Quantum Manipulation of Non-equilibrium Superconductor Phases and their Collective Modes
• Theory of ultrafast exciton dynamics in the Quantum Hall system
• Observation of inter-Landau-level quantum coherence in semiconductor quantum wells
• Large optical gain from four-wave mixing instabilities in semiconductor quantum wells
• Unlocking Quantum Control and Multi-Order Correlations via Terahertz Two-Dimensional Coherent Spectroscopy
• Nonlinear Optical studies of the Transient Coherence in the Quantum Hall System
• Two-dimensional magnetoexcitons in the presence of spin-orbit coupling