Influence of growth temperature on structural and magnetic characterization of (In, Cr)As quantum dots

(In, Cr)As ferromagnetic semiconductor quantum dots (QDs) were grown by molecular beam epitaxy on GaAs (001) substrates. The growth temperature effects on structure and magnetism of the QDs were investigated systematically. The Cr(2+)3d(4) states and quantum confined effect are assumed to play an important role in the room-temperature ferromagnetism of (In, Cr)As QDs. (C) 2009 Elsevier B.V. All rights reserved.

National Natural Science Foundation of China 60836002 106741301071031560521001Major State Basic Research Contract of China 2007CB924903 Chinese Academy of Sciences KJCX2.YW.W09-1 The authors acknowledge S. Yan, K.K. Meng and S.L Wang for their help on sample preparation, H.Y. Zhang for SQUID measurements and Z.Y. Cheng for TEM measurements. This work was supported partly by the National Natural Science Foundation of China under Grant Nos. 60836002, 10674130, 10710315, 60521001 and the special funds for the Major State Basic Research Contract No. 2007CB924903 of China, and the Knowledge Innovation Program Project of Chinese Academy of Sciences No. KJCX2.YW.W09-1.