Mutual interaction

Elham Razzazi

Dan Anderson, M. Lisak

Mutual interaction between soliton pulses may severely limit the maximum bit rate of a soliton-based optical communication system. We present explicit analytical results for soliton separation as a function of propagation distance in the presence of mutual pulse interaction. In particular, we find that soliton coalescence can be avoided by proper phase shifting of consecutive pulses and that a phase shift of π/2 minimizes the initial mutual interaction.

Willy Haeberli

Giampaolo Co’

Lin Ma, Zhiguo Jiang, Jifang Liu +1 more

Based on the four-wave mixing mechanism and fanning effect, the threshold coupling constant for mutually pumped phase conjugator (MPPC) with one interaction region and two interaction regions is studied in theory. The relation of the the threshold coupling strength for MPPC and the fanning intensity is studied. Due to the more efficient fanning, preset grating in MPPC has the ability to reduce threshold coupling constant and improve output efficiency. These characteristics predicted by theory have been used to explain the previous experiment phenomenon. The dependence of threshold coupling constants for MPPC on the amplitude ratio of incident pump beams is presented. The threshold coupling constant for one-interaction-region MPPC is lower than that for two-interaction-regions MPPC.

Guofeng Zhang

Mutual information and swap operation in the two-qubit Heisenberg model with the Dzyaloshinskii–Moriya (DM) anisotropic antisymmetric interaction are investigated. It is found that the mutual information I of such a quantum channel is sensitive to the initial conditions and declines with increase in temperature. The DM interaction can lead to higher mutual information, especially for the ferromagnetic case. The entanglement quality of input states cannot enhance the mutual information of the quantum channel. When the DM interaction is large, the mutual information will have the maximum value of 2 for a non-entangled input state, but it is 1 for a maximally entangled input state. It is also shown that the swap operation can be implemented for some kinds of DM coupling. The conditions of the DM coupling under which the swap operation is feasible are established.