Metal–insulator switching of vanadium dioxide for controlling spin-wave dynamics in magnonic crystals

Abstract

The present work focuses on the effect of vanadium dioxide (VO2) films exhibiting a metal-insulator transition (MIT) on performance characteristics of the magnetic multilayers. It has been shown that the MIT provides a novel mechanism for controlling the microwave spin-wave dynamics in the yttrium-iron garnet (YIG) films. In particular, the low and high levels of microwave attenuation of spin waves transmitted through the YIG-VO2 bilayer has been observed due to a variation of the VO2 conductivity within a narrow temperature range. This effect has been utilized to realize fully reconfigurable magnonic crystals composed of the thickness-modulated YIG and regular VO2 films. Promising functionality of the proposed waveguiding structures arises from a controllability of wave intensity, which provides altering of the frequency response from an original band structure to a full rejection of spin waves.Numerical simulations taking into account both the YIG-film saturation magnetization and the VO2-film conductivity have confirmed the experimentally observed spin-wave dynamics. An interest in ferrite-VO2 bilayers arises not only from possible practical applications, but also from a variety of fundamental scientific problems devoted to physics of wave phenomena in planar thin-film magnetic multilayers.

Modeling and design of a Mott selector for a ReRAM-based non-volatile memory cell in a crossbar architecture

“…For example, the relative permittivity of VO2 is changed from 36 in the insulator phase to 6×10 4 (real part) in the metallic phase at 100 °C [35]. This indicates that the time constants for IMT and MIT are in the same order [29].…”

“…Consequently, we expect the IMT and MIT switching time for the selector to be in the range of 1 to 2ns. A simple RC model is proposed in [29] to approximate the time constant for the transition. After the transitioning to the metallic phase, the electrical resistance of the selector decreases by several orders, but on the other hand, the dielectric constant of VO2 increases [35].…”

Dynamic electromagnonic crystals based on ferrite-ferroelectric thin film multilayers

“…Investigations of a wide variety of linear [4][5][6] and nonlinear [7][8][9] spin-wave phenomena address the field of science known as magnonics. The promising building blocks for magnonic devices are constituted by artificial spatially periodic magnetic media, known as magnonic crystals [10][11][12][13][14][15][16][17]. Their functionality arises from a band structure engineering that is mainly caused by spin-wave Bragg reflections from periodic disturbances.…”