Terahertz-Frequency Signal Source Based on an Array of Synchronized Antiferromagnetic Spin Hall Oscillators

Abstract

Terahertz-frequency (TF) signals have a great potential for applications in medicine, security, communications, etc., but many of these applications require the development of compact, reliable and rather powerful sources of coherent TF signals, which are able to operate in the absence of cryogenic temperatures, strong bias magnetic fields and large bias voltages. One of the promising types of such sources can be a source utilizing an array of synchronized antiferromagnetic (AFM) spin Hall oscillators (SHOs). In this paper we theoretically and numerically study electrodynamic properties of a TF source based on a high-quality dielectric resonator with embedded current-biased mutually synchronized AFM SHOs, where an AFM layer of each SHO is made of a canted AFM with non-zero net magnetization. Since the location of AFM SHOs inside the resonator has influence on the excitation conditions of resonator’s oscillation modes, we study an impact of AFM SHO array spatial configuration on the performance of considered TF source and find optimum spatial configuration of the SHOs array for different excited E- and H-modes. The obtained results could be important for the development of novel micro- and nano-scale TF signal sources based on antiferromagnets.