Voltage control of magnetism

• Online Access: http://hdl.handle.net/2047/d20005069

In past decades, attracted by the increasing demand of compact, fast, and low energy consumption RF/microwave devices, many researchers have devoted their efforts to realizing electric field control of magnetism, instead of magnetic field. For instance, within traditional RF/microwave devices, ferromagnetic resonance are controlled by bulky, noisy, slow and energy consumption electromagnets. This limits its application in many important, low mass and energy consuming requirement carriers, such as aircraft, satellites, radars and communication devices. As a result, novel functional material, which can be integrated into non-volatile, light, and energy-efficient electronic devices, need to be discovered. Multiferroics, a composite material combined with ferromagnetic material and ferroelectric material, is widely studied as a great candidate for E-field tunable RF/microwave applications like tunable resonators, phase shifters, tunable inductors and tunable filters. The coexistence of ferroelectricity and ferromagnetism in multiferroics introduces interaction between ferroelectric property and ferromagnetic properties, therefore, allowing electric field (E-field) control of ferromagnetism through varying mechanism. In our work, different mechanism-based magnetoelectric (ME) coupling in multiferroics heterostructure was investigated for the development of novel generation, voltage-controllable, high-speed, compact RF/microwave devices with greater energy efficiency.