Cryogenic Voltage Control of Magnetism in Silicon-Integrated \newline SrTiO$_3$/Fe Heterostructures

Abstract

Cryogenic electronics forms a rapidly emerging research domain for high-performance and power-efficient computing applications. Incorporating nanomagnetic components in cryogenic circuitry adds highly valuable functionality, facilitating downscaling, reducing energy consumption and introducing time-reversal symmetry breaking. Furthermore, low-temperature environments enhance magnetic stability and switching efficiency at nanoscale dimensions, reinforcing the potential of cryogenic nanomagnets. To fully leverage these opportunities, magnetic control schemes require alternative options to current-based writing, which is the main bottleneck regarding power consumption and downscaling. In this regard, voltage-based gating of the magnetic state could drastically enhance operational efficiency and integration density. In this work, we investigate cryogenic Voltage Control of Magnetism (VCM) in epitaxial SrTiO$_3$/Fe thin film heterostructures on a CMOS compatible Si substrate. We demonstrate and quantify voltage-controlled modifications of the magnetic domain structure, consistent with electric field-controlled magnetic anisotropy at the Fe/SrTiO$_3$ interface. These findings provide a viable material system for the development of next-generation magnetic domain-based devices for classical and quantum computing.