Visualizing revivals and fractional revivals in a Kerr medium using optical tomogram

Abstract

We theoretically study the optical tomography of the time evolved states generated by the evolution of different kinds of initial wave packets in a Kerr medium. Exact analytical expression for the optical tomogram of the quantum state at any instant during the evolution of a generic initial wave packet is derived in terms of Hermite polynomials. Time evolution of the optical tomogram is discussed for three kinds of initial states: a coherent state, an $m$-photon-added coherent state, and even and odd coherent states. We show the manifestation of revival and fractional revivals in the optical tomograms of the time evolved states. We find that the optical tomogram of the time evolved state at the instants of fractional revivals shows structures with sinusoidal strands. The number of sinusoidal strands in the optical tomogram of the time evolved state at $l$-sub-packet fractional revivals is $l$ times the number of sinusoidal strands present in the optical tomogram of the initial state. We have also investigated the effect of decoherence on the optical tomograms of the states at the instants of fractional revivals for the initial states considered above. We consider amplitude decay and phase damping models of decoherence, and show the direct manifestations of decoherence in the optical tomogram.