HgCdTe反型层的磁输运性质

Magnetotransport property of HgCdTe inversion layer

利用成本低廉的液相外延技术,成功制备了具有金属-绝缘体-半导体结构的HgCdTe场效应管器件.在该器件中,观察到清晰的Shubnikov-de Hass振荡和量子霍尔平台,证明样品具有较高的质量.测量零场附近的磁阻曲线,在HgCdTe-基器件中观察到反弱局域效应,表明样品中存在较强的自旋-轨道耦合作用.利用Iordanskii-Lyanda-Pikus理论,很好地拟合了反弱局域曲线.由拟合得到的自旋分裂能随电子浓度的增大而增大,最大达到9.06 meV根据自旋分裂能得到的自旋-轨道耦合系数同样随电子浓度的增大而增大,与沟道较宽的量子阱中所得到的结果相反.

HgCdTe-based metal-insulator-semiconductor field effect transistor is fabricated by low-cost liquid phase epitaxy technique. Clear SdH oscillation inρ_（xx） and quantum Hall plateaus ofρ_（xy） are observed,indicating that it is a good transistor.By measuring the magnetoresistance near zero field,we observe the weak antilocalization effect in our sample,suggesting a relatively strong spinorbit coupling.The experimental data can be well fitted by the ILP theory.The fitting-obtained spin-splitting energy increases with increasing electron concentration,and the maximum reaches up to 9.06 meV.From the obtained spin-splitting energy,we calculate the spin-orbit coupling parameter and find that it increases with increasing electron concentration,which is contrary to the observations in a wide quantum well.