Accession Number:

AD1101676

Title:

Electrical Detection of Charge-to-Spin and Spin-to-Charge Conversion in a Topological Insulator Bi2Te3 Using Bn/Al2O3 Hybrid Tunnel Barrier

Descriptive Note:

Journal Article - Open Access

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC WASHINGTON United States

Report Date:

2018-07-06

Pagination or Media Count:

8.0

Abstract:

One of the most striking properties of three-dimensional topological insulators TIs is spin-momentum locking, where the spin is locked at right angles to momentum and hence an unpolarized charge current creates a net spin polarization. Alternatively, if a net spin is injected into the TI surface state system, it is distinctively associated with a unique carrier momentum and hence should generate a charge accumulation, as in the so-called inverse Edelstein effect. Here using a FeAl2O3BN tunnel barrier, we demonstrate both effects in a single device in Bi2Te3 the electrical detection of the spin accumulation generated by an unpolarized current flowing through the surface states, and that of the charge accumulation generated by spins injected into the surface state system. This work is the first to utilize BN as part of a hybrid tunnel barrier on TI, where we observed a high spin polarization of 93 for the TI surfaces states. The reverse spin-to-charge measurement is an independent confirmation that spin and momentum are locked in the surface states of TI, and offers additional avenues for spin manipulation. It further demonstrates the robustness and versatility of electrical access to the spin system within TI surface states, an important step towards its utilization in TI-based spintronics devices.

Subject Categories:

  • Electrical and Electronic Equipment
  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE