NANOSCALE

LI XX, LI B, FAN XD, WEI LM, LI L, TAO R, ZHANG XQ, ZHANG H, ZHANG Q, ZHU HB, ZHANG SB, ZHANG ZY, ZENG CG

PHYSICAL REVIEW LETTERS

CUI P, ZHANG Q, ZHU HB, LI XX, WANG WY, LI QX, ZENG CG, ZHANG ZY