Spin squeezing properties of an initial coherent state via a two-axis countertwisting Hamiltonian in the presence and absence of an external fleld
Ahmad Akhound, Mojtaba Jafarpour · Journal of Physics Conference Series · 2008
We consider a four-qubit system, initially in a coherent state along the z-axis, and study its time dependence under the influence of the well-known two-axis countertwisting Hamiltonian. Analyzing the time dependence of the spin operators, we observe its squeezing properties, according to the criterion given by Kitagawa et al. We also perform similar calculations for the same Hamiltonian in the presence of an external fleld and compare its squeezing properties with that of the former. It is observed that the details of the squeezing properties are difierent in the two cases. Plots of the squeezing parameters as a function of time and the rotation angle for both cases are presented.