Non classical Effects in Highly Nonlinear Two-Level Spin Models

HORACIO GRINBERG

San Carlos de Bariloche

Congreso; 98 Reunión Nacional de la Asociación Física Argentina; 2013

Centro Atómico Bariloche

The non classical squeezing effect emerging from a nonlinear coupling model (generalized Jaynes-Cummings model) of a two-level atom interacting with a bimodal cavity field via two-photon transitions is investigated in the rotating wave approximation. Various Bloch coherent initial states (rogated states) for the atomic system are assumed. initially the atomic system and the field are in a disentangled state, where the field modes are in Glauber coherent states via Poisson distribution. The model is numerically tested against simulations of time evolution of the based Heisenberg uncertainty variance and Shannon information entropy squeezing factors. The quantum state purity is computed and used as a crierion to get information about the entanglement of the components of the system. Analytical expression of the total density operator matrix elements at t > 0 shows in fact, the present nonlinear model bo be strongly entangled, where each of the definite initial Bloch coherent states are reduced to statistical mixtures. Thus, the present model does not preserve the modulus of the Bloch vector. References [1] H. Grinberg, J. Phys. Chem. B, 112 (50), 16140-16157 (2008) [2] H. Grinberg, Int. J. Model Phys. B, 24 (9), 1079-1092 (2010) [3] H. Grinberg, Phys. Lett. A 374, 1481-1487 (2010) [4] H. Grinberg, Annals Phys., 326 (11), 2845-2867 (2011)