摘要
通过在低温和强磁场下的磁输运测量研究了非故意掺杂Al0.24Ga0.76N/GaN异质结构中二维电子气(2DEG)的磁电阻振荡现象。在强磁场下观察到了表征2DEG塞曼自旋分裂的舒勃尼科夫-德哈斯(SdH)振荡的分裂峰。通过分析SdH分裂峰的位置,获得了塞曼自旋分裂能量和g*的大小,发现由于交换相互作用,g*比g0有了显著的增加,同时g*随着磁场的增大而增大,说明随着磁场的增大,电子与电子的交换相互作用增强。
Magnetoresistance oscillations of the two-dimensional electron gas(2DEG)in unintentionally doped Al0.24Ga0.76N/GaN heterostructures have been investigated by means of magnetotransport measurements at low temperatures and high magnetic fields.The spin-split peaks of the Shubnikov-de Haas(SdH)oscillations are observed at high magnetic fields,which are attributed to the Zeeman spin splitting of the 2DEG.The spin splitting energy and g are obtained by measuring the positions of the pairs of spin-split SdH maxima.It is found that g is enhanced over its bulk value in GaN due to the exchange interactions.Moreover,the g increase with an increase in magnetic field,indicating that many-body electron-electron interactions become stronger as the magnetic field increases.
出处
《半导体技术》
CAS
CSCD
北大核心
2008年第S1期147-149,共3页
Semiconductor Technology
基金
国家"973"重点基础研究项目(2006CB604908
2006CB921607)
国家自然科学基金(60806042
10774001
60736033
60628402)
教育部博士点基金(200800011021
20060001018)
北京市自然科学基金(4062017)
