Superradiance of polaritons: Crossover from two-dimensional to three-dimensional crystals

Abstract

Enhancement of spontaneous emission rate and reduction in amplified spontaneous emission threshold in electrodeposited three-dimensional ZnO photonic crystal

Superradiance of low-density Frenkel excitons in a crystal slab of three-level atoms: The quantum interference effect

“…The enhanced factor (λ/a) D in the radiative width of exciton is now regarded commonly as one of evidences of "superradiance" 10 , which has been demonstrated in experiments for Frenkel excitons 13 and Wannier excitons 14 . Since the enhanced radiant effect can also appear in the usual superradiance of an ensemble of atoms 15,16 , how can we distinguish the different features between the fluorescence of the excitons and that of the atomic ensemble?…”

“…It is well known that the fluorescence of an exciton exhibits super-radiant character due to the appearance of macroscopic transition dipole moment of the exciton [1][2][3][4][5][6][7][8][9][10][11][12] . However this collective feature of exciton radiance depends upon dimensionality of crystal.…”

Generation of entangled-photon pairs from biexcitons in CuCl thin films: Nano-to-bulk crossover regime

“…37 The spectral shape can be interpreted by the exciton-photon coupled modes 17,18,21,32,33,35 in the thin film, which have been discussed in relation with the radiative decay of excitons in nano-to-bulk crossover regime. [22][23][24][25] Due to the breaking of translational symmetry in z direction, the lower and upper polaritons in bulk material are no longer good eigen states, but instead we obtain the excitonphoton coupled modes with discrete energy levels and radiative decay rates in the case of thin films. A created biexciton spontaneously decays into these coupled modes with emitting a photon conserving the energy and in-plane wavevector.…”

“…19,20 When the crystal size is comparable or a few times larger than the wavelength (nano-to-bulk crossover regime), the system is characterized by exciton-photon coupled modes with peculiar resonance energy and radiative life time, and the coupled modes are gradually reduced to bulk polaritons with increasing the crystal size. 18,[21][22][23][24][25] In this crossover regime, the system shows a variety of optical responses compared to bulk materials and also to quantum dots due to the center-of-mass confinement of excitons and the spatially resonant coupling with electromagnetic fields. Actually, owing to the recent development of nanoscale fabrication, anomalous nonlinear optical processes have been reported in semiconductor nano-structures and in the nano-to-bulk crossover regime.…”

Decay rate and renormalized frequency shift of a quantum wire Wannier exciton in a planar microcavity

“…In V. M. Agranovich et al's work [16], a detailed microscopic study of Frenkel exciton-polariton in crystal slabs of arbitrary thickness was performed.…”