Local insulator-to-superconductor transition in amorphous InO\(_x\) films modulated by e-beam irradiation

We present a novel method enabling precise post-fabrication modulation of the electrical resistance in micrometer-scale regions of amorphous indium oxide (a-InO\(_x\)) films. By subjecting initially insulating films to an electron beam at room temperature, we demonstrate that the exposed region of the films becomes superconducting. The resultant superconducting transition temperature (\(T_c\)) is adjustable up to 2.8 K by changing the electron dose and accelerating voltage. This technique offers a compelling alternative to traditional a-InO\(_x\) annealing methods for both fundamental investigations and practical applications. Moreover, it empowers independent adjustment of electrical properties across initially identical a-InO\(_x\) samples on the same substrate, facilitating the creation of superconducting microstructures with precise \(T_c\) control at the micrometer scale. The observed resistance modifications likely stem from photoreduction induced by X-ray and/or UV radiation emitted during electron beam interactions with the film and substrate.