- 5月24日 (水), 13:30-
- 京都大学理学部 5号館 413
- Ms. Rina Takashima
- (Condensed Matter Theory Group)
- "Manipulation of magnetic moment by supercurrent"
Abstract: Applications of superconductivity offer new possibilities in spintronics. Spin valves using superconductors show colossal magnetoresistance effects, and the lifetime of spin density is enhanced in a superconducting state relative to a normal state. While interesting aspects of spintronics with the proximity-induced superconductivity have been reported, it is not well understood how a supercurrent acts on magnetic moments. We study spin transfer torques (STT) induced by a spin-triplet supercurrent in a magnet with the superconducting proximity effect . STT have attracted much attention for controlling magnetization by applied currents, and the magnetization dynamics sensitively depends on the direction of STT. By a perturbative approach, we show that spin-triplet correlations realize a new type of torque, which is analogous to the adiabatic and non-adiabatic torques. We demonstrate that this torque realizes an efficient manipulation of a domain wall. If time allows, I will also talk on (a) Spin-orbit torques and quasi-particle structure in a chiral magnet with singlet superconductivity, (b) Supercurrent induced noncollinear magnetic order. Reference:  e.g., J. Linder and J. W. A Robinson, Nat. Phys. 11, 307 (2015)  RT, S. Fujimoto, and T. Yokoyama (to be submitted)  RT and S. Fujimoto, Phys. Rev. B 94, 235117 (2016)