Limiting factor of defect-engineered spin-filtering effect at room temperature

作者:Puttisong Y*; Buyanova I A; Chen W M
来源:Physical Review B, 2014, 89(19): 195412.
DOI:10.1103/PhysRevB.89.195412

摘要

We identify hyperfine-induced electron and nuclear spin cross-relaxation as the dominant physical mechanism for the longitudinal electron spin relaxation time (T-1) of the spin-filtering Ga-i(2+) defects in GaNAs alloys. This conclusion is based on our experimental findings that T-1 is insensitive to temperature over 4-300 K, and its exact value is directly correlated with the hyperfine coupling strength of the defects that varies between different configurations of the Ga-i(2+) defects present in the alloys. These results thus provide a guideline for further improvements of the spin-filtering efficiency by optimizing growth and processing conditions to preferably incorporate the Ga-i(2+) defects with a weak hyperfine interaction and by searching for new spin-filtering defects with zero nuclear spin.

  • 出版日期2014-5-12