Quantum Actions on Conducting Electron Spins in Semiconductors
Shun-Tsung Lo1*
1Department of Electrophysics, National Chiao Tung University, Hsinchu, Taiwan
* Presenter:Shun-Tsung Lo, email:stlo@nctu.edu.tw
Quantum actions on electron spins have long been tantalizing for fundamental research and targeted for various applications in semiconductors either of strong or weak spin-orbit interactions. Semiconductors of strong spin-orbit interactions provide a platform to control conducting electron spins with on-chip electric and magnetic fields. However, the conventional transistor scheme is incapable of simultaneously resolving up and down spins, which has posed a difficult challenge in the individual control of their spin dynamics even in the presence of on-chip fields [1, 2]. Here we demonstrate full control of spin dynamics using the interplay between an external magnetic field and spin-orbit interactions in a gated InGaAs heterostructure [3]. However, the on-chip fields do not work efficiently with lowering the strength of spin-orbit interactions. Here, we further develop dot-wire hybrids in gated GaAs heterostructures of weak spin-orbit interactions, where the conducting channel for electron spins is shown to be tunable by setting the dot-wire potential configuration [4, 5]. These findings pave a promising route to decorate conducting electron spins for the applications of quantum spintronics in semiconductors.

[1] S. Datta and B. Das, Appl. Phys. Lett. 56, 665 (1989).
[2] H. C. Koo, J. H. Kwon, J. Eom, J. Chang, S. H. Han, and M. Johnson, Science 325, 1515 (2009).
[3] Shun-Tsung Lo, Chin-Hung Chen, Ju-Chun Fan, L. W. Smith, G. L. Creeth, Che-Wei Chang, M. Pepper, J. P. Griffiths, I. Farrer, H. E. Beere, G. A. C. Jones, D. A. Ritchie, and T.-M. Chen, Nat. Commun. 8, 15997 (2017).
[4] Shun-Tsung Lo, Che-Cheng Wang, Ming-Wei Chen, G. L. Creeth, L. W. Smith, Chi-Te Liang, M. Pepper, J. P. Griffiths, I. Farrer, G. A. C. Jones, D. A. Ritchie, and Tse-Ming Chen, in preparation.
[5] Shun-Tsung Lo, Jun-Hao Chang, Sheng-Chin Ho, G. L. Creeth, M. Pepper, J. P. Griffiths, I. Farrer, G. A. C. Jones, D. A. Ritchie, and Tse-Ming Chen, in preparation.

Keywords: electron spins, spin-orbit interactions, heterostructures, dot-wire hybrids