Antiferromagnetic Spin Wave Field-Effect Transistor

Spin waves are propagating spin precessions in a magnetically ordered medium. Since spin waves can carry pure spin currents in the absence of electron flow, they are considered to be potential information carriers for low dissipation, wave-based computing technologies. In a collinear antiferromagnet with easy-axis anisotropy, symmetry dictates that the spin wave modes must be doubly degenerate. These two modes, distinguished by their opposite polarization and available only in antiferromagnets, give rise to a novel degree of freedom for information encoding and processing. Here we show that the spin wave polarization can be manipulated by an electric field induced Dzyaloshinskii-Moriya interaction and magnetic anisotropy. We propose a prototype spin wave field-effect transistor which realizes a gate-tunable magnonic analog of the Faraday effect, and demonstrate its applications in terahertz signal modulation and pure spin wave logic gates. Our findings open up the exciting possibility for digital data processing of antiferromagnetic spin waves and enable the direct projection of optical computing concepts onto the nanometer scale.