Wide-range continuous tuning of the thermal conductivity of $\mathrm{L}{\mathrm{a}}_{0.5}\mathrm{S}{\mathrm{r}}_{0.5}\mathrm{Co}{\mathrm{O}}_{3-\delta }$ films via room-temperature ion-gel gating

Abstract

Solid-state control of the thermal conductivity of materials is of exceptional interest for novel devices such as thermal diodes and switches. Here, we demonstrate the ability to continuously tune the thermal conductivity of nanoscale films of $\mathrm{L}{\mathrm{a}}_{0.5}\mathrm{S}{\mathrm{r}}_{0.5}\mathrm{Co}{\mathrm{O}}_{3-\delta }$ (LSCO) by a factor of over 5, via a room-temperature electrolyte-gate-induced non-volatile topotactic phase transformation from perovskite (with $\delta \approx 0.1$) to an oxygen-vacancy-ordered brownmillerite phase (with $\delta =0.5$), accompanied by a metal-insulator transition. Combining time-domain thermoreflectance and electronic transport measurements, model analyses based on molecular dynamics and Boltzmann transport, and structural characterization by X-ray diffraction, we uncover and deconvolve the effects of these transitions on heat carriers, including electrons and lattice vibrations. The wide-range continuous tunability of LSCO thermal conductivity enabled by low-voltage (below 4 V) room-temperature electrolyte gating opens the door to non-volatile dynamic control of thermal transport in perovskite-based functional materials, for thermal regulation and management in device applications.

References in corpus (11)

• Reversible redox reactions in an epitaxially stabilized SrCoOx oxygen sponge
• Topotactic phase transformation of the brownmillerite SrCoO2.5 to the perovskite SrCoO3-δ
• On the Lorenz number of multi-band materials
• Thermal Conductivity, Thermopower, and Figure of Merit of La_{1-x}Sr_xCoO_3
• Accurate Measurements of Cross-plane Thermal Conductivity of Thin Films by Dual-Frequency Time-Domain Thermoreflectance (TDTR)
• On the Calculation of Lorenz Numbers for Complex Thermoelectric Materials
• Electric-field control of oxygen vacancy and magnetic phase transition in cobaltite/manganite bilayer
• Reversibly switchable electromagnetic device with leakage-free electrolyte
• Thermal Boundary Conductance Across Metal-Nonmetal Interfaces: Effects of Electron-Phonon Coupling both in Metal and at Interface
• Giant Electrostatic Modification of Magnetism via Electrolyte-Gate-Induced Cluster Percolation in La${}_{1-x}$Sr${}_x$CoO${}_{3-\delta }$
• Soft X-ray Absorption Spectroscopy and Magnetic Circular Dichroism as Operando Probes of Complex Oxide Electrolyte Gate Transistors

Cited by in corpus (3)

• High-performance solid-state electrochemical thermal switches with earth-abundant cerium oxide
• Solid-State Electrochemical Thermal Transistors with Large Thermal Conductivity Switching Widths
• Thermodynamics of proton insertion across the perovskite-brownmillerite transition in La0.5Sr0.5CoO3-δ