标题： Li原子系统的量子相变和纠缠 显示英文标题

标题： Quantum phase transition and entanglement in Li atom system

摘要： 本文利用精确对角化方法研究了自旋s1=1/2和s2=1的自旋对系统中的量子相变与纠缠。 我们表明，对于这个完全可解的量子双自旋系统，纠缠在量子相变之前出现，在量子相变之后消失。 此外，我们还表明，作为纠缠度量的冯·诺依曼熵可以揭示该系统的量子相变。 显示英文摘要

摘要： In this paper we study the quantum phase transition and entanglement in s1=1/2 and s2=1 spin pair system by the exact diagonalization method. We show that, for this exactly solvable quantum bi-spin system, entanglement appears before quantum phase transition and disappears after it. Moreover, we show that the von Neumann entropy, as a measure of entanglement, can reveal quantum phase transition in this system.