Quantum well thickness dependence of spin orbit interaction in gated InP/In0.8Ga0.2As/In0.52Al0.48As asymmetric quantum wells

✍ Scribed by Makoto Kohda; Takayuki Nihei; Junsaku Nitta

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 247 KB
• Volume: 40
• Category: Article
• ISSN: 1386-9477
• DOI: 10.1016/j.physe.2007.08.088

✦ Synopsis

We have investigated the influence of the quantum well (QW) thickness for the gate controlled Rashba spin orbit interaction (SOI) in InP/In 0.8 Ga 0.2 As/In 0.52 Al 0.48 As asymmetric QWs from the analysis of the weak antilocalization. We prepared two different samples with 5 and 10 nm In 0.8 Ga 0.2 As QWs. Gate bias dependence of the Rashba SOI parameter a shows inverse dependence between 5 and 10 nm QWs, where the a for 5 nm QW increases while that for 10 nm QW decreases with increasing the gate bias voltage. By comparing the obtained a with the interface and the field contributions of Rashba SOI calculated by the k Á p formalism, the opposite dependence of the a is resulted in the enhancement of the interface contribution in 5 nm QW due to the large electron probability at the InP/In 0.8 Ga 0.2 As interface, whereas the dominant contribution for the a is originated from the In 0.8 Ga 0.2 As field contribution in 10 nm QW.