14:15 〜 14:30
▲ [23p-E205-4] Origin of giant gate-controllable odd-parity magnetoresistance in InAs/(Ga,Fe)Sb heterostructure
キーワード：Ferromagnetic semiconductor, magnetoresistance
Investigation of new magnetoresistance (MR) is an important issue in condensed matter physics, magnetism and spintronics. Generally, MR curves (resistance R – external magnetic field B) are even functions of B according to Onsager’s principle. However, it may not be the case when time reversal symmetry (TRS) is broken by magnetism. The odd parity MR (OMR) in a linear response regime is a novel phenomenon only observed in some exotic materials. Even in such rare material systems, the OMR magnitude is typically very subtle (the magnitude reported thus far is at most 2%), and it can only be realized when the magnetic field B and the magnetization M are anti-parallel.
Recently, we reported a giant and gate-controlled OMR in the edge transport channels of a nonmagnetic (NM) InAs ultrathin film interfaced with a ferromagnetic (FM) semiconductor (Ga,Fe)Sb layer. The OMR is unprecedently large; the resistance change is 27% of the total resistance when the B direction is reversed between ± 10 T at I = 1 μA , in which the OMR can be realized even in a large magnetic field, where B//M. However, the reason why the OMR can be achieved in a linear response regime and under the condition B//M is still unclear. In this presentation, we will discuss the detailed physical mechanism of the OMR in InAs/(Ga,Fe)Sb. We propose a possible scenario which involves asymmetric chirality-dependent scattering between the two-dimensional channel and the 1D channels in the InAs layer, where the chirality is determined by spin-momentum locking due to the Rashba spin-orbit interactions in each channel.
Recently, we reported a giant and gate-controlled OMR in the edge transport channels of a nonmagnetic (NM) InAs ultrathin film interfaced with a ferromagnetic (FM) semiconductor (Ga,Fe)Sb layer. The OMR is unprecedently large; the resistance change is 27% of the total resistance when the B direction is reversed between ± 10 T at I = 1 μA , in which the OMR can be realized even in a large magnetic field, where B//M. However, the reason why the OMR can be achieved in a linear response regime and under the condition B//M is still unclear. In this presentation, we will discuss the detailed physical mechanism of the OMR in InAs/(Ga,Fe)Sb. We propose a possible scenario which involves asymmetric chirality-dependent scattering between the two-dimensional channel and the 1D channels in the InAs layer, where the chirality is determined by spin-momentum locking due to the Rashba spin-orbit interactions in each channel.