College;
of;
Physics;
and;
Communication;
Electronics,;
Jiangxi;
Normal;
University;
Nanchang;
330027;
Department;
of;
Physics,;
the;
State;
Key;
Laboratory;
on;
Fiber;
Optic;
Local;
Area;
Communication;
Networks;
and;
Advanced;
Optical;
Communication;
Systems,;
Shanghai;
Jiao;
Tong;
University,;
Shanghai;
200240;