PHYSICS LETTERS A

LUO W, QIN SQ, LONG MS, LIU EF, FU YJ, ZHOU W, MIAO F, ZHANG S, ZHANG RY, ZHANG XA

APPLIED PHYSICS LETTERS

GAO AY, LIU EF, LONG MS, ZHOU W, WANG YY, XIA TL, HU WD, WANG BG, MIAO F