Room temperature observation of high spin polarization in post annealed Co2FeSi/MgO/n+-Si on insulator devices

Ajay Tiwari, Tomoaki Inokuchi, Mizue Ishikawa, Hideyuki Sugiyama, Nobuki Tezuka, Yoshiaki Saito

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


The post annealing temperature dependence of room temperature spin signals in Co2FeSi/MgO/n+-Si on insulator fabricated on Si(2×1) surface was investigated. For the devices fabricated on the Si(2×1) surface, the large and reliable three- and four-terminals spin signals were obtained even at room temperature. The magnitude of three-terminal narrow Hanle signals has a peak around 325 °C with respect to post annealing temperature. The trend of increasing spin accumulation signal with decreasing bias voltage was observed for both as deposited and sample annealed at 325 °C in the bias voltage range 600-800mV. The enhancement of three- and four-terminals non-local magnetoresistance (MR) for post annealed sample at 325 °C, indicates that the spin polarization increases due to the structural ordering of Heusler alloy Co2FeSi. As a result, we observed large spin injection efficiency into Si (P > 41.7%) even at room temperature. These results will pave a way to the future Si spintronics devices such a spin-MOSFET.

Original languageEnglish
Article number04CD05
JournalJapanese journal of applied physics
Issue number4
Publication statusPublished - 2017 Apr

ASJC Scopus subject areas

  • Engineering(all)
  • Physics and Astronomy(all)


Dive into the research topics of 'Room temperature observation of high spin polarization in post annealed Co<sub>2</sub>FeSi/MgO/n+-Si on insulator devices'. Together they form a unique fingerprint.

Cite this