NANO LETTERS

DAI JY, WANG DX, ZHANG M, NIU TC, LI A, YE M, QIAO S, DING GQ, XIE XM, WANG YQ, CHU PK, YUAN QH, DI ZF, WANG X, DING F, YAKOBSON BI

SMALL

YANG C, WU TR, WANG HM, ZHANG GH, SUN JL, LU GY, NIU TC, LI A, XIE XM, JIANG MH