Evolution of the magnetoresistance lineshape with temperature and electric field across Nb-doped SrTiO${}_3$ interface

Abstract

We report on the temperature and electric field driven evolution of the magnetoresistance lineshape at an interface between Ni/AlO${}_x$ and Nb-doped SrTiO${}_3$. This is manifested as a superposition of the Lorentzian lineshape due to spin accumulation and a parabolic background related to tunneling anisotropic magnetoresistance (TAMR). The characteristic Lorentzian line shape of the spin voltage is retrieved only at low temperatures and large positive applied bias. This is caused by the reduction of electric field at large positive applied bias which results in a simultaneous reduction of the background TAMR and a sharp enhancement in spin injection. Such mechanisms to tune magnetoresistance are uncommon in conventional semiconductors.

References in corpus (9)

• Electrical Detection of Spin Transport in Lateral Ferromagnet-Semiconductor Devices
• Enhancement of the Spin Accumulation at the Interface Between a Spin-Polarized Tunnel Junction and a Semiconductor
• Theory of t2g electron-gas Rashba interactions
• Nanoscale Phenomena in Oxide Heterostructures
• Efficient Spin Injection into Silicon and the Role of the Schottky Barrier
• Magnetic-Field-Modulated Resonant Tunneling in Ferromagnetic-Insulator-Nonmagnetic junctions
• Impurity-assisted tunneling magnetoresistance under weak magnetic field
• Electrical transport across Au/Nb:SrTiO3 Schottky interface with different Nb doping
• Electric field control of spin lifetimes in Nb-SrTiO${}_3$ by spin-orbit fields