APPLIED PHYSICS LETTERS

YAN H, LIU CC, BAI KK, WANG XJ, LIU MX, YAN W, MENG L, ZHANG YF, LIU ZF, DOU RF, NIE JC, YAO YG, HE L

APPLIED PHYSICS LETTERS

ZHU XL, YAN W, JEPSEN PU, HANSEN O, MORTENSEN NA, XIAO SS