Triggering phase-coherent spin packets by pulsed electrical spin injection across an Fe/GaAs Schottky barrier

L. R. Schreiber, C. Schwark, G. Güntherodt, M. Lepsa, C. Adelmann, C. J. Palmstrøm, X. Lou, P. A. Crowell, B. Beschoten

Research output: Contribution to journalArticlepeer-review

Abstract

The precise control of spins in semiconductor spintronic devices requires electrical means to generate spin packets with a well-defined initial phase. We demonstrate a pulsed electrical scheme that triggers the spin ensemble phase in a similar way as circularly polarized optical pulses generate phase coherent spin packets. Here, we use fast current pulses to initialize phase coherent spin packets, which are injected across an Fe/GaAs Schottky barrier into n-GaAs. By means of time-resolved Faraday rotation, we demonstrate phase coherence by the observation of multiple Larmor precession cycles for current pulse widths down to 500 ps at 17 K. We show that the current pulses are broadened by the charging and discharging time of the Schottky barrier. At high frequencies, the observable spin coherence is limited only by the finite bandwidth of the current pulses, which is of the order of 2 GHz. These results therefore demonstrate that all-electrical injection and phase control of electron spin packets at microwave frequencies is possible in metallic-ferromagnet-semiconductor heterostructures.

Original languageEnglish (US)
Article number195202
JournalPhysical Review B
Volume104
Issue number19
DOIs
StatePublished - Nov 15 2021
Externally publishedYes

Bibliographical note

Funding Information:
This work was supported by HGF and by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under SPP 1285 (Grant No. 40956248). C.J.P. and P.A.C. acknowledge funding from the U.S. Office of Naval Research, the National Science Foundation (NSF) MRSEC program, the NSF NNIN program, and the University of Minnesota.

Publisher Copyright:
© 2021 American Physical Society.

Fingerprint

Dive into the research topics of 'Triggering phase-coherent spin packets by pulsed electrical spin injection across an Fe/GaAs Schottky barrier'. Together they form a unique fingerprint.

Cite this