Properties of spin squeezing in the quantum kicked tops model

In this paper, by using QKT model, we give the changing relation between chaotic coefficient k and spin squeezing coefficient of two different definitions by numerical simulation calculation. The results show that the regular regions are stronger than chaotic ones in the classical phase space, the spin squeezed behavior is very strong, and the chaotic regions are stronger than regular ones in the classical phase space, the spin squeezed behavior is very weak, which indicate the spin squeezing is very sensitive to the corresponding classical chaos. Through the comparison we also know that the spin squeezing coefficient defined by Wineland is more sensitive to the classical chaos than the one by Kitagawa and Ueda, so the quantum chaos can be described by spin squeezing.