Thermally driven analog of the Barkhausen effect at the metal-insulator transition in vanadium dioxide

Abstract

Abstract:The physics of the metal-insulator transition (MIT) in vanadium dioxide remains a subject of intense interest. Because of the complicating effects of elastic strain on the phase transition, there is interest in comparatively strain-free means of examining VO 2 material properties. We report contact-free, low-strain studies of the MIT through an inductive bridge approach sensitive to the magnetic response of VO 2 powder. Rather than observing the expected step-like change in susceptibility at the transition, we argue that the measured response is dominated by an analog of the Barkhausen effect, due to the extremely sharp jump in the magnetic response of each grain as a function of time as the material is cycled across the phase boundary. This effect suggests that future measurements could access the dynamics of this and similar phase transitions. Text:Vanadium dioxide is a showcase for the rich physics possible in correlated transition metal oxides, where strong electron-electron and electron-phonon interactions lead to competition between phases with vastly differing electronic properties. With zero strain, VO 2

Barkhausen effect in the first order structural phase transition in type-II Weyl semimetal MoTe 2

“…The Barkhausen effect has been a powerful tool to characterize magnetic and ferroelectric materials [24][25][26][27], and it has also attracted growing interest as an example of complex dynamical systems displaying dimensiondependent scaling behavior [22]. Given the ubiquitous presence of the Barkhausen effect in magnetic phase transition [24][25][26][27][28][29], only a limited number of research has revealed Barkhausen physics in thermally-driven first-order phase transition in non-magnetic materials [30][31][32][33][34][35], and none of such transition has been observed in van der Waals layered crystals.…”