1National Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083
2National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083
3National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093
Magnetointersubband Oscillations of the Two-Dimensional Electron Gas in AlxGa1-xN/GaN Heterostructures
1National Laboratory for Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, PO Box 912, Beijing 100083
2National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083
3National Laboratory of Solid State Microstructures and Department of Physics, Nanjing University, Nanjing 210093
Abstract： Shubnikov-de Haas (SdH) measurements are performed over a temperature range of 1.5-20 K in Al0.22Ga0.78N/GaN heterostructures with two subbands occupied. In addition to an intermodulation between two sets of SdH oscillations from the first and second subbands, a beating in oscillatory magnetoresistance at 12 K is observed, due to the mixing of the first subband SdH oscillations and `magnetointersubband' (MIS) oscillations. A phase shift of π between the SdH and MIS oscillations is also clearly identified. Our experimental results, i.e. that the SdH oscillations dominate at low temperature and MIS oscillations dominate at high temperature, fully comply with the expected behaviour of MIS oscillations.
2004, Vol. 21 
