Kohda, M. and Lechner, Vera and Kunihashi, Y. and Dollinger, Tobias and Olbrich, Peter and Schönhuber, Christoph and Caspers, Ines and Belkov, Vassilij and Golub, Leonid and Weiss, Dieter and Richter, Klaus and Nitta, J. and Ganichev, Sergey (2012) Gate-controlled persistent spin helix state in (In,Ga)As quantum wells. Physical Review B (PRB) 8 (86), 081306.
In layered semiconductors with spin-orbit interaction (SOI) a persistent spin helix (PSH) state with suppressed spin relaxation is expected if the strengths of the Rashba and Dresselhaus SOI terms, α and β, are equal. Here we demonstrate gate control and detection of the PSH in two-dimensional electron systems with strong SOI including terms cubic in momentum. We consider strain-free InGaAs/InAlAs quantum wells and first determine a ratio α/β≃1 for nongated structures by measuring the spin-galvanic and circular photogalvanic effects. Upon gate tuning the Rashba SOI strength in a complementary magnetotransport experiment, we monitor the complete crossover from weak antilocalization via weak localization to weak antilocalization, where the emergence of weak localization reflects a PSH-type state. A corresponding numerical analysis reveals that such a PSH-type state indeed prevails even in presence of strong cubic SOI, however no longer at α=β.
|Date:||27 August 2012|
|Institutions:|| Physics > Institute of Theroretical Physics > Chair Professor Richter > Group Klaus Richter|
Physics > Institute of Experimental and Applied Physics > Professor Ganichev > Group Sergey Ganichev
Physics > Institute of Experimental and Applied Physics > Chair Professor Lupton > Group John Lupton
Physics > Institute of Experimental and Applied Physics > Chair Professor Weiss > Group Dieter Weiss
|Subjects:||500 Science > 530 Physics|
|Refereed:||Yes, this version has been refereed|
|Created at the University of Regensburg:||Yes|
|Deposited On:||22 Nov 2012 10:08|
|Last Modified:||22 Nov 2012 10:08|