Visualizing Electromagnetic Properties of Matters Using Ultrasonic Techniques

Abstract

We review a unique ultrasonic method to detect and image electromagnetic properties of matters. The principle of this method is based on the generation and detection of acoustically stimulated electromagnetic (ASEM) fields originating from electro- or magneto-mechanical coupling. In this paper, we focus on magnetic sensing via ultrasonic excitation. We discuss the mechanism of ASEM response in ferromagnetic materials and demonstrated magnetic imaging and magnetic hysteresis measurements using ultrasonic techniques. This method will be a viable tool not only for nondestructive material inspection but also for fundamental studies of acoustically excited spin dynamics or spin resonance in magnetic thin films and spin devices.