单模压缩信道的纠缠辅助容量

Entanglement assisted capacity of single-mode squeezed channel

用量子特性函数方法得到了纠缠辅助单模压缩信道在限定输入功率下的经典信息容量的表达式,并进行了数值分析.计算结果表明,信道压缩参数越大,其容量也越大.与没有纠缠辅助下的单模压缩信道的信道容量不同,在纠缠辅助下信道容量一般在信源为压缩态时达到,且此时信源与信道的压缩复参数的相角关系相差π.

In this paper the way of quantum characteristic function is applied to acquire the presentation of the entanglement assistant capacity of single mode squeezed channel for classic information with input signal in limited power. The computed result indicates that the capacity becomes larger with increasing the squeezing parameter of the channel. The single mode squeezed channel with entanglement assistant will attain its capacity when the state of input signal is squeezed, which is different from the one without entanglement assistant. At the same time the difference between the squeezing parameter's phase angles of signal and channel is π.