Polariton and spin dynamics in semiconductor microcavities under non-resonant excitation

Wang

J. Phys.: Condens. Matter

2019

We study the topological phase transition with the TE-TM splitting in the p-orbital excitonpolariton honeycomb lattice. We find that some Dirac points survive at the high-symmetry points with space-inversion symmetry breaking, which reflects the characteristic of p orbitals. A phase diagram is obtained by the gap Chern number, from which the topological phase transition takes place in the intermediate gap. There is no topological phase transition in the bottom or top gap, and its edge state has the potential application for transporting signals in optoelectronic devices. When taking into account the non-degenerate p orbitals, we find that the bottom gap arises owing to the competition between the Zeeman energy and rotating angular velocity, and topological phase transition also appears in the complete gaps. These results can facilitate the experimental investigations of the topological properties of p-orbital exciton-polariton lattice structure.

Section: Introductionmentioning

confidence: 99%

Topological phase transition with p orbitals in the exciton-polariton honeycomb lattice

Wang

J. Phys.: Condens. Matter

2019

Physica Status Solidi (b)

“…Similar oscillations at the high excitation density with a period of about 30 ps independent of the excitation density and spot position on the sample were reported in Refs. and attributed to the quantum beats between bright exciton–polaritons and dark excitons. We attribute the observed oscillations to the beatings between different lasing modes (originated from the axial modes of the external resonator) in the multimode generation regime.…”

Section: Resultsmentioning

confidence: 99%

Effect of an external resonator on the stimulated emission of a semiconductor microcavity with embedded quantum wells

Belykh

Mylnikov

2015

The effect of an external resonator on the emission of a GaAs microcavity with embedded quantum wells is investigated experimentally and theoretically. It was shown that the external resonator controls the process of the stimulated emission of the microcavity leading to the threshold-like appearance of closely separated modes in a spectrum and to oscillations in the temporal dynamics of the emission. Investigation of the spatial coherence with a temporal resolution shows a complex phase dynamics related to the interplay between the lasing modes and reveals a strong spatial inhomogeneity of a phase within each mode. [7] and the relation between polariton and photon BEC and a conventional laser is actively discussed [8][9][10][11][12]. It should be noted, however, that true BEC in a pure two-dimensional system, such as an ideal planar MC, is impossible according to the HohenbergMermin-Wagner theorem [13]. Therefore, polariton condensation observed in the experiments results from the finite size of the system, which is limited either by the excitation spot or by a lateral confining potential for polaritons. This potential is formed by an MC lateral disorder [5,14,15], applied stress [16], or artificially by producing MC micropillars [17,18]. It provides a favorable condition for the polariton condensation [16] and leads to a significant modification of

Semicond. Sci. Technol.

“…For instance, the steady state of the system is given by the interplay between pumping, relaxation and decay, and not by a thermodynamic equilibrium. Additionally, very rich spin physics are found in these systems, which can be directly accessed via the polarization control of the excitation and detected fields (Martín et al 2007b, Shelykh et al 2010. Several terms like condensate, polariton laser and Bose-Einstein condensate, are used in the literature to refer to related but subtly different phenomena with respect to the coherent phases of polaritons in semiconductor microcavities.…”

Section: Polariton Condensatesmentioning

confidence: 99%

Collective dynamics of excitons and polaritons in semiconductor nanostructures

Amo

Sanvitto²,

Viña³

2010

Self Cite

Time resolved photoluminescence is a powerful technique to study the collective dynamics of excitons and polaritons in semiconductor nanostructures. We present a two excitation pulses technique to induce the ultrafast and controlled quenching of the exciton emission in a quantum well. The depth of the dip is given by the magnitude of the warming of the carriers induced by the arrival of a laser pulse when an exciton population is already present in the sample. We use this technique to study the relaxation mechanisms of polaritons in semiconductor microcavities, which are of great importance to enhance the conditions for their condensation under non-resonant excitation. We also explore the dynamics of polariton fluids resonantly created in the lower polariton branch in a triggered optical parametric oscillator configuration, showing evidence of polariton superfluidity, and opening up the way to the real-time study of quantum fluids. ‡ Present address: