A Magnetic Field-to-Digital Converter Employing a Spin-Torque Nano-Oscillator

Abstract

In this work, a novel magnetic field-to-digital converter based on emerging spin-torque nano-oscillators (STNOs) is proposed. The architecture is inspired by voltage controlled oscillator (VCO)-based analog-to-digital converters (ADCs) which have shown inherent first-order noise shaping of both quantization-and phase-noise without the need for feedback. In the proposed architecture, the STNO acts both as a magnetic field sensor and VCO. The architecture's performance is evaluated in terms of signal-to-noise and distortion ratio (SNDR) utilizing Verilog-AMS modeling, where a macrospin model fitted to experimental data is employed for accurate description of the STNO operation. The presented simulation results demonstrate the potential of the STNO-based magnetic field-to-digital converter architecture.

Field-Free High-Frequency Exchange-Spring Spin-Torque Nano-Oscillators

“…These nanoscale nonlinear oscillators are capable of generating various magnetodynamic modes, such as propagating spin-waves, − localized bullets, , magnetic droplets, − dynamic vortex, , and dynamic skyrmions . During the past decades, tremendous attention has been paid to their applications in, for instance, signal generators, spectrum analyzers, , spin diodes, − wireless communication, − microwave-assisted magnetic random-access memories, , Ising machines, and neuromorphic computing, − due to their capability of generating highly tunable ultrawide microwave signals ranging from hundreds of megahertz to tens of gigahertz …”

Nanoscale magnetic field sensing with spin-Hall nano-oscillator devices

“…3,12 In addition to the aforementioned sensors, the oscillations of nanoscale magnetization driven by the spintransfer torque 13 from spin-polarized current in an electrical device (a spin-torque nano-oscillator, STNO) have been proposed as a nanoscale sensing candidate. 1,[14][15][16] However, the quantification of the sensor detectivity in such devices is lacking.…”