Generation of pair and bi-pair coherent states

Fabio Bagarello

Fabio Bagarello

Yong-Nan Sun, Yang Zou, Geng Chen +8 more

The inhomogeneous broadening of the bi-exciton state in quantum dots, i.e., the inhomogeneous broadening of the upper level of the cascade process, is not only a fundamental problem in quantum dots, but also closely related with the coherent control of this complex system and the quality of the entangled photon pairs, especially the time-bin entangled photon pairs. This inhomogeneous broadening is inherently a two-photon correlated phenomenon. In this work, we construct a genuine Franson-type nonlocal interference process to measure the inhomogeneous broadening of the bi-exciton state. The results show that the inhomogeneous broadening of the bi-exciton state is considerably smaller than that of the exciton state, that is why the entangled photon pairs can be generated by the cascade process in the quantum dot.

Yong Wook Cheong, Jinhyoung Lee

Bindu A. Bambah, G. S. Agarwal

We introduce and study the properties of a class of coherent states for the group SU(1,1)\ifmmode\times\else\texttimes\fi{}SU(1,1) and derive explicit expressions for these using the Clebsch-Gordan algebra for the SU(1,1) group. We also derive a phase space representation based on pair coherent states rather than the standard harmonic-oscillator coherent states. We discuss the utility of the resulting ``bi-pair coherent states'' in the context of four-mode interactions in quantum optics.

Pranshu Maan