NANO LETTERS

GUO H, ZHANG RZ, LI H, WANG XY, LU HL, QIAN K, LI G, HUANG L, LIN X, ZHANG YY, DING H, DU SX, PANTELIDES ST, GAO HJ

CHINESE PHYSICS B

MENG L, WANG YL, ZHANG LZ, DU SX, GAO HJ