Creating of exciton drops in the exciton–phonon field

V M Nandakumaran, K. P. Sinha

Ka‐Di Zhu, Xiao-Zhong Yuan, Jingxin Dong +1 more

Yang Zhao, Paolo Zanardi A, Guanhua Chen

We revisit from a quantum-information perspective a classic problem of polaron theory in one dimension. In the context of the Holstein model we show that a simple analysis of quantum entanglement between excitonic and phononic degrees of freedom allows one to effectively characterize both the small and large polaron regimes as well as the crossover in between. The small (large) polaron regime corresponds to a high (low) degree of bipartite quantum entanglement between the exciton and the phonon cloud that clothes the exciton. Moreover, the self-trapping transition is clearly displayed by a sharp drop of exciton-phonon entanglement.

Vitaly V. Osipov

Bohdan M. Nitsovich, Claudia Yu. Zenkova, S. G. Kharinovich

This paper proposes for consideration an additional mechanism for influencing the exciton absorption spectra and observing temperature redistribution peculiarities of the crystal absorptive power. They are caused by nonlinear phonon-exciton interactions, which are due to anharmonic effects in the exciton-phonon system. The arising of the borderline frequency, which possesses the smallest region of optical bistability realization, is caused by a break in the direction of the absorption curve. At low temperatures the basic role is played by the exciton-exciton interaction, and at high temperatures nonlinear exciton-exciton-phonon processes play the most important role the value of the borderline frequency is defined by the size and sign of the nonlinear exciton-exciton-phonon function as well as by the crystal temperature and the exciton density, which is created by the external powerful laser wave.