Picosecond Time of Flight Measurements of Excitonic Polariton in CuCl

Photon Localization Revisited

“…With a slight improvement through the wavenumber dependence of the exciton energy, the theoretical result of polariton group velocity ∂ω/∂k < c based on the above dispersion relation can explain satisfactorily the experimental data of the passing time of light in materials (for example, [12]). This strongly supports the validity of the polariton picture.…”

“…In general, this dispersion relation implies branching, analogous to the Higgs mechanism. The signal pulse corresponding to each branch can also be detected in many experiments, for example in [12] cited below. In the simple case, the permittivity is given by the transverse frequency ω T of the exciton (lattice vibration) as follows:…”

Optical Dephasing of Excitonic Polaritons in CuCl Studied by Time-Resolved, Nondegenerate Four-Wave Mixing

“…2, the experimentally confirmed dispersion relation and the group velocity of excitonic polaritons in CuCl are illustrated together with the calculated transit time of the excitonic polariton pulse through the sample of 14.15 /im thickness. 4 The transit time of the co 2 pulse through the sample is 1.4-1.5 ps, while that of the oo 1 pulse varies from 3.88 ps to several hundred picoseconds. The correlation traces 1 to 6 show asymmetry tailed toward t 2 -t 1 >0.…”

Slowing Down of Light in Photorefractive Crystals with Beam Intensity Coupling Reduced to Zero

“…Just the strong dispersion mentioned above ensures a dramatic decrease of the light group velocity [1] in a similar way as for other narrow resonances like those related, e.g., to excitons in semiconductors [6], to EIT in gases [2], to a narrow quantum coherence ''hole'' in the homogeneously broadened absorption line of ruby [7,8].…”