Quantum interference of spontaneous-emission channels near the surface of Bi2Se3

We show that the quantum interference between two spontaneous emission channels can be significantly enhanced when a three-level V-type atom is placed near the surface of the topological insulator [Formula: see text]. The enhancement of quantum interference is a result of the strong dependence of the spontaneous emission rate on the orientation of an atomic dipole relative to surface of the [Formula: see text] at the frequencies of polaritonic-type excitations.

Hyperradiance by a stream of phase-correlated atomic dipole pairs traversing a high-Q cavity

Hyperradiance in which radiation rate exceeds that of superradiance has been theoretically investigated in various coherently-coupled emitter-field systems. In most cases, either proposed setups were experimentally challenging or the mean photon number in a cavity was limited. In this paper, with numerical simulations and analytic calculations, we demonstrate that significant hyperradiance with a large mean photon number can occur in a microlaser system, where pairs of two-level atoms prepared in quantum superposition states traverse a high-Q cavity in the presence of a pump field intersecting the cavity mode. Hyperradiance is induced when the intracavity-pump Rabi frequency is out of phase with respect to the atom-cavity coupling so that the reduction of atomic polarization by the atom-cavity coupling is compensated by the pump Rabi frequency in the steady state to maximize atomic photoemission.

Особенности затухания свободной поляризации в ультратонких газовых ячейках

Optical effect of the free polarization decay is studied theoretically in the ultrathin gas cell whose inner thickness is less or order of the wavelength of exciting monochromatic laser pulse transmitted orthogonally to plane-parallel walls of the cell. New mechanism of the investigated effect is established which is caused by specifics of phase mismatch of light induced atomic dipole moments because of transit-time relaxation in such a cell. As a result, dynamics of the free polarization decay in the considered situation radically different from the known case in a usual (macroscopic) gas cell. Nontrivial oscillatory dependences of signals of the free polarization decay on the ratio of thickness of such a cell to the radiation wavelength of the exciting pulse have been discovered and analyzed.