Unconventional spin polarization at Argon ion milled SrTiO3 Interfaces

Amrendra Kumar; Utkarsh Shashank; Suman Kumar Maharana; John Rex Mohan; Surbhi Gupta; Hironori Asada; Yasuhiro Fukuma; Rohit Medwal

arXiv · 2307.12390

Unconventional spin polarization at Argon ion milled SrTiO3 Interfaces

Amrendra Kumar·Utkarsh Shashank·Suman Kumar Maharana·John Rex Mohan·Surbhi Gupta·Hironori Asada·Yasuhiro Fukuma·Rohit Medwal

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Abstract

Interfacial two-dimensional electron gas (2DEG) formed at the perovskite-type oxide, such as SrTiO3, has attracted significant attention due to its properties of ferromagnetism, superconductivity, and its potential application in oxide-based low-power consumption electronics. Recent studies have investigated spin-to-charge conversion at the STO interface with different materials, which could affect the efficiency of this 2DEG interface. In this report, we presented an Ar^+ ion milling method to create a 2DEG at STO directly by inducing oxygen vacancies. To quantify the spin-to-charge conversion of this interface, we measured the angular-dependent spin-torque ferromagnetic resonance (ST-FMR) spectra, revealing an unconventional spin polarization at the interface of Argon ion-milled STO and NiFe. Furthermore, a micromagnetic simulation for angular-dependent spin-torque ferromagnetic resonance (ST-FMR) has been performed, confirming the large unconventional spin polarization at the interface.

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Amrendra Kumar, Utkarsh Shashank, Suman Kumar Maharana, John Rex Mohan, Surbhi Gupta, Hironori Asada, Yasuhiro Fukuma, Rohit Medwal. 2023-07-23. Unconventional spin polarization at Argon ion milled SrTiO3 Interfaces. https://arxiv.org/abs/2307.12390

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