氧化物薄膜在基底中印入动态非对称应变

PhYsics Dynamic asymmetric strain imprinted into substrates by an oxide thin film In film- substrate systems, the substrate role is often considered to be limited to providing static mechanical constraints. Dynamic film- substrate interactions when a structural change in the film modifies the substrate are generally disregarded. using combined x- ray and electron microscopies, we observed that an electrically induced filament in a vanadium dioxide film created strong asymmetric strain in an underlying sapphire substrate. This asymmetric substrate strain fed back into the film and defined the filament expansion direction, revealing the importance of film- substrate dynamic interactions in determining film functionality. …