Solid-State Electrochemical Switch of Superconductor–Metal–Insulators

Abstract

Controlling the oxygen content can manipulate the electrical conductivity of transition metal oxides (TMOs). Although the superconductor–metal–insulator transition is useful for functional devices, an electrical path must be developed to manipulate the oxygen deficiency (δ) while maintaining the solid state. YBa2Cu3O7−δ (YBCO, 0 ≤ δ ≤ 1) is a high transition temperature (T c) TMO that can be modulated from a superconductor (T c ≈ 92 K when δ = 0) to an insulator (δ ≈ 1). Here, we show a simple and efficient way to manipulate δ in YBCO films using a solid-state electrochemical redox treatment. Applying a negative voltage injects oxide ions to the YBCO films, increasing T c. Employing a positive voltage suppresses the superconducting transition and modulates the electrical conductivity. The present results demonstrate that the superconductor–metal–insulator transition of YBCO is modulated electrochemically in the solid state, opening possibilities of superconducting oxide-based device applications.

Solid‐State Electrochemical Thermal Transistors

“…Most importantly, many perovskite‐related TMOs are heteroepitaxially grown on YSZ single‐crystal substrates. [ 18–20 ]…”

“…Most importantly, many perovskite-related TMOs are heteroepitaxially grown on YSZ single-crystal substrates. [18][19][20] In this study, we focus on SrCoO x (2 ≤ x ≤ 3) as the active material for a solid-state electrochemical thermal transistor. SrCoO x is known as an oxygen sponge, and the O 2− ion concentration of SrCoO x can be controlled at relatively low temperatures.…”