Ultrathin complex oxide nanomechanical resonators

Abstract

Complex oxide thin films and heterostructures exhibit a variety of electronic phases, often controlled by the mechanical coupling between film and substrate. Recently it has become possible to isolate epitaxially grown single-crystalline layers of these materials, enabling the study of their properties in the absence of interface effects. In this work, we use this technique to create nanomechanical resonators made out of SrTiO 3 and SrRuO 3 . Using laser interferometry, we successfully actuate and measure the motion of the nanodrum resonators. By measuring the temperature-dependent mechanical response of the SrTiO 3 resonators, we observe signatures of a structural phase transition, which affects both the strain and mechanical dissipation in the resonators. Here, we demonstrate the feasibility of integrating ultrathin complex oxide membranes for realizing nanoelectromechanical systems on arbitrary substrates and present a novel method of detecting structural phase transitions in these exotic materials. Thin films of complex oxides can be grown and transferred on substrates, which provides opportunities for their manipulation, characterization and potential applications. Here, the authors fabricate and characterize nanodrum resonators of suspended thin single-crystal complex oxides and investigate the temperature dependent properties and associated phase transitions of the isolated ultrathin form.