Mechanisms for producing lattice absorption: one or two? (A)

J. Ďurček

Dong-Ik Lee, Theodore G. Goodson III

Entanglement is one of the most fundamental and significant features in quantum mechanics. The spatial parameters of the correlated photon pairs were investigated in order to improve the entanglement property within the correlated photon flux. The focus of the work is to utilize the properties of entanglement and novel materials to produce new sensitive detection schemes. Through this focus, we demonstrated one of the most important applications of quantum effects, namely entangled two-photon absorption spectroscopy.

Jacob P. Covey

J.P. Heritage, A. Von Lehmen, Jane E. Zucker +1 more

We have investigated the optical properties of GaAs quantum wells in the spectral region below the band edge using a two-wavelength picosecond optical pulse technique. Optical pumping in the transparent region produces modulation of the excitonic absorption which is probed with an optical pulse tuned to the excitonic absorption. We identify two distinct physical mechanisms that lead to the absorption modulation. First, a real population of carriers is produced by phonon-assisted absorption. These carriers bleach the excitonic transition by the action of the exclusion principle. The second mechanism involves virtual populations induced by the off-resonant optical excitation.

T. K. Lim, George F. Caudle, Jerald R. Izatt

Tao Hong, Michael W. Jack, Makoto Yamashita

We propose a method for producing on-demand single-photon states based on collision-induced exchanges of photons and unbalanced linear absorption between two single-mode light fields. These two effects result in an effective nonlinear absorption of photons in one of the modes, which can lead to single-photon states. A quantum nonlinear attenuator based on such a mechanism can absorb photons in a normal input light pulse and terminate the absorption at a single-photon state. Because the output light pulses containing single photons preserve the properties of the input pulses, we expect this method to be a means for building a highly controllable single-photon source.