TY - JOUR
T1 - Control of the spin geometric phase in semiconductor quantum rings
AU - Nagasawa, Fumiya
AU - Frustaglia, Diego
AU - Saarikoski, Henri
AU - Richter, Klaus
AU - Nitta, Junsaku
N1 - Funding Information:
We acknowledge support from Strategic Japanese-German Joint Research Program. H.S. and K.R. thank DFG for support within Research Unit FOR 1483. D.F. acknowledges support from the Ramón y Cajal program, from the Spanish Ministry of Science’s project No. FIS2011-29400, and from the Junta de Andaluca’s Excellence Project No. P07-FQM-3037. F.N. and J.N. are grateful to M.Kohda for valuable discussions. J.N. thanks N.Nagaosa for valuable discussions. This work was financially supported by Grants-in-Aid from the Japan Society for the Promotion of Science (JSPS) No. 22226001.
PY - 2013
Y1 - 2013
N2 - Since the formulation of the geometric phase by Berry, its relevance has been demonstrated in a large variety of physical systems. However, a geometric phase of the most fundamental spin-1/2 system, the electron spin, has not been observed directly and controlled independently from dynamical phases. Here we report experimental evidence on the manipulation of an electron spin through a purely geometric effect in an InGaAs-based quantum ring with Rashba spin-orbit coupling. By applying an in-plane magnetic field, a phase shift of the Aharonov-Casher interference pattern towards the small spin-orbit-coupling regions is observed. A perturbation theory for a one-dimensional Rashba ring under small in-plane fields reveals that the phase shift originates exclusively from the modulation of a pure geometric-phase component of the electron spin beyond the adiabatic limit, independently from dynamical phases. The phase shift is well reproduced by implementing two independent approaches, that is, perturbation theory and non-perturbative transport simulations.
AB - Since the formulation of the geometric phase by Berry, its relevance has been demonstrated in a large variety of physical systems. However, a geometric phase of the most fundamental spin-1/2 system, the electron spin, has not been observed directly and controlled independently from dynamical phases. Here we report experimental evidence on the manipulation of an electron spin through a purely geometric effect in an InGaAs-based quantum ring with Rashba spin-orbit coupling. By applying an in-plane magnetic field, a phase shift of the Aharonov-Casher interference pattern towards the small spin-orbit-coupling regions is observed. A perturbation theory for a one-dimensional Rashba ring under small in-plane fields reveals that the phase shift originates exclusively from the modulation of a pure geometric-phase component of the electron spin beyond the adiabatic limit, independently from dynamical phases. The phase shift is well reproduced by implementing two independent approaches, that is, perturbation theory and non-perturbative transport simulations.
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U2 - 10.1038/ncomms3526
DO - 10.1038/ncomms3526
M3 - Article
C2 - 24067870
AN - SCOPUS:84885142967
VL - 4
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
M1 - 2526
ER -