自旋为1的系统的量子非经典性度量

Measuring nonclassicality in spin-1 state

相干态最初在1960年由Klauder和Sudarshan提出.基于此,许多经典性和非经典性的度量被提出.1971年Radcliffe提出了原子相干态,但基于原子相干态的非经典性度量研究仍然较少.本文利用原子自旋相干态的特征提出一种度量非经典性的方法,并讨论了这种度量的若干性质,例如转动算符作用下的不变性和纯态的非经典性.我们给出了一些计算例子,例如猫态、NOON态和混合态.这种度量只在自旋为1的系统上讨论.这些结果对探索量子非经典性的度量和量子资源理论有一定的意义,也对实验室利用非经典性度量起到积极作用.

Coherent states were first proposed by Klauder and Sudarshan in 1960.Based on this,many classical and nonclassical measures of light have been introduced.In 1971,Radcliffe proposed atomic coherent state,but the nonclassical measures based on atomic coherent state are still seldom studies.In this paper,by using the characteristics of the atomic spin coherent states,we introduce a method to measure nonclassicality and discuss some properties of this measure.For example,the invariance under the action of rotation operator and the nonclassicality of pure state.Some computational examples,such as cat state,NOON state and mixed states are given.This measure is only discussed in the spin-1 system.These results will have certain significance for exploring the measurement of quantum nonclassicality and quantum resource theory.It will also play a positive role in utilizing nonclassicality measure in the laboratories.