Abstract: The entangled property of Yurke-like state was investigated via spin squeezing. Since the state is superposed by a symmetric state and two special multi-particle states, the entangled property can be studied by investigating superposition coefficient and relative phase’s influence on spin squeezing parameter; the analytical results for the optimal squeezed direction and the optimal squeezing were obtained via minimizing. Its shown that the spin squeezing parameter monotonously changes with superposition coefficients and periodically changes with relative phase. Its also shown that the more the number of the particles is, the stronger the degree of squeezing will be.

Key words: quantum optics, spin squeezing, Yurke-like state, optimal squeezed direction