Signatures of the excitonic memory effects in four-wave mixing processes in cavity polaritons

We report the signatures of the exciton correlation effects with finite memory time in frequency domain degenerate four-wave mixing (DFWM) in semiconductor microcavity. By utilizing the polarization selection rules, we discriminate instantaneous, mean field interactions between excitons with the same spins, long-living correlation due to the formation of biexciton state by excitons with opposite spins, and short-memory correlation effects in the continuum of unbound two-exciton states. The DFWM spectra give us the relative contributions of these effects and the upper limit for the time of the exciton-exciton correlation in the unbound two-exciton continuum. The obtained results reveal the basis of the cavity polariton scattering model for the DFWM processes in high-Q GaAs microcavity.Comment: 11 pages, 1 figur

Propagation of partially polarized light

We present a general formalism describing the evolution of partially polarized light propagating in a medium with cubic nonlinearity. Within the ergodic approximation we found that totally polarized coherent single-mode light remains totally polarized, irrespective of the type of optical medium. Partially polarized light consisting of a mixture of a coherent component with a random one preserves its degree of polarization in a dissipation-free medium with isotropic nonlinearity, while only linear or nonlinear dissipation may lead to alteration of the degree of polarization. We also found that in some crystal symmetry point groups, a time-nonreversible optical response may be the only reason for an alteration of the degree of polarization

Coherent and incoherent pump-probe specular inverse Faraday-effect in media with instantaneous nonlinearity

A wave theory of the specular inverse Faraday effect (SIFE) that reveals the existence of coherent and incoherent terms of the phenomenon is presented. Recovery of various cubic nonlinear tensor components from the SIFE observation in transparent and opaque materials is examined

Experimental observation of specular optical activity

We report the first positive experimental observation of the optical activity effect on normal reflection. The experiment was performed along the optic axis in a gyrotropic semiconductor crystal of α-HgS, cinnabar, in a spectral region of strong absorption. Reflected light polarization azimuth rotation resulting from the reflection is in the order of 10-4 rad and has pronounced dependence on hω-Eg

Broken symmetry of the kinetic coefficients and specular optical activity

The optical consequences of the violation of thermodynamic equilibrium in a crystal are investigated. If this violation occurs it may lead to breaking of time reversibility. As a result of this the internal symmetry of the optical susceptibility tensors changes and new "forbidden" tensor components arise. This gives way to some forbidden specular polarization phenomena in optics, observation of which may be used for diagnostics of the crystal equilibrium. The wave theory of normal reflection from a crystal interface including consideration of the role of the forbidden components is developed. Two mechanisms for forbidden specular polarization effects are identified, one due to the appearance of a contribution to the dielectric tensor which is antisymmetric under interchange of tensor indices, and another associated with the symmetric contribution to the nonlocal optical response. Crystal point group analysis shows that, depending on crystal class, forbidden specular polarization effects may be seen with or without a background of "conventional" optical activity. The physical conditions for their observation are discussed and recent polarization-sensitive experiments in optically excited GaAs crystals are explained in terms of the developed theory. It is also shown how this approach may be used for the description of time-reversal-symmetry-breaking specular optical activity in the superconducting phase of high-Tc cuprate materials

On equivalency of the Casimir and the Landau-Lifshits approach to optical electrodynamics

The controversial discussion on the existence of the specular optical activity phenomenon is reexamined. We prove here that the effect is predicted by approaches based both on the Casimir and the Landau-Lifshitz material equations and that these equations are in fact equivalent if crucial terms containing the derivatives of the nonlocal susceptibilities are taken into account in the derivation. Polarization azimuth rotation in the reflected wave of the scale 2×10-6 to 2×10-4 rad may be expected in absorbing optically active crystals. We also show that specular optical activity is intrinsically linked with the transmission effect

Observation of time-nonreversible optical interaction with zincblende semiconductors

Light-induced specular rotation resulting from a time-nonreversible nonreciprocal interaction of light with semiconductors of zinc-blende structure is reported. The rotation increases with pump intensity at the rate of 1.1×10-11 rad W-1 cm-2 in GaAs and 4.3×10-11 rad W-1 cm-2 in InSb and does not disappear immediately after the end of the excitation, but partially decays on a subnanosecond time scale

Giant polarization rotation by a nonmagnetic cubic crystal in linear reflection

We believe we report the first observation of gyrotropic linear dichroism near-excitonic resonance. The magnitude of the effect is sensitive to the linear term of the exciton dispersion as well as to the crystal orientation