Spin injection into a superconductor with strong spin-orbit coupling

T. Wakamura, N. Hasegawa, Kohei Ohnishi, Y. Niimi, Yoshichika Otani

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

We demonstrate spin injection into superconducting Nb by employing a spin absorption technique in lateral spin valve structures. Spin currents flowing in a nonmagnetic Cu channel are preferably absorbed into Nb due to its strong spin-orbit interaction, the amount of which dramatically changes below or above the superconducting critical temperature (TC). The charge imbalance effect observed in the Cu/Nb interface ensures that superconducting Nb absorbs pure spin currents even below TC. Our analyses based on the density of states calculated using the Usadel equation can well reproduce the experimental results, implying that the strong spin-orbit interaction of Nb is still effective for the spin absorption even below TC. Most importantly, our method allows us to determine the intrinsic spin relaxation time in the superconducting Nb, which reaches more than 4 times greater than that in the normal state.

Original languageEnglish
Article number036602
JournalPhysical Review Letters
Volume112
Issue number3
DOIs
Publication statusPublished - Jan 24 2014
Externally publishedYes

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injection
orbits
spin-orbit interactions
critical temperature
relaxation time

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy(all)

Cite this

Spin injection into a superconductor with strong spin-orbit coupling. / Wakamura, T.; Hasegawa, N.; Ohnishi, Kohei; Niimi, Y.; Otani, Yoshichika.

In: Physical Review Letters, Vol. 112, No. 3, 036602, 24.01.2014.

Research output: Contribution to journalArticle

Wakamura, T. ; Hasegawa, N. ; Ohnishi, Kohei ; Niimi, Y. ; Otani, Yoshichika. / Spin injection into a superconductor with strong spin-orbit coupling. In: Physical Review Letters. 2014 ; Vol. 112, No. 3.
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