Functional materials are applied in a variety of technological applications as they possess properties that can be significantly controlled by external stimuli such as a change in temperature or applying electric field, magnetic field, or stress. In recent years, a category of functional materials known as magnetoelectrics has drawn enormous attention because of the internal connection between the electrical and magnetic properties. This means that one can control their electrical properties by applying magnetic field, or conversely, their magnetic properties by applying electric field. Such control would allow scientists and engineers to design more sophisticated and novel devices such as storage media with significantly lower power consumption and magnetic sensors and read heads with much higher sensitivity. Two current roadblocks for functional materials being tested in such applications are small magnetoelectric response and functionality at very low temperature. This study proposes an approach which could significantly enhance the response of Bismuth Ferrite (also known as BFO), which is one of the few magnetoelectrics with functionality at room temperature. Such approach is based on a mechanism in which three quasiparticles are mixed to form a new quasiparticle that we coined “electroacoustic magnons”. This mechanism provides opportunities to engineer the size and shape of the material to reach strikingly larger magnetoelectric responses. In this study, an analytical model to explain the origin of electroacoustic magnons is derived and also confirmed with atomistic simulations through the facilities of High Performance Computing Centers.
The outcomes would allow scientists and engineers to design more sophisticated and novel devices such as storage media with significantly lower power consumption and magnetic sensors and read heads with much higher sensitivity.