Wacky oxides: Rich properties in search of devices

摘要

Until recently, the word “oxide” could only mean one thing to the device research community—SiO. But as is being increasingly realized, oxides are an exciting class of electronic materials in their own right. Oxides exhibit the full spectrum of electronic, optical, and magnetic behavior: insulating, semiconducting, metallic, superconducting, ferroelectric, pyroelectric, piezoelectric, ferromagnetic, multiferroic, and non-linear optical effects are all possessed by structurally-compatible oxides. Further, the properties of a given composition can change drastically as it goes through phase transitions that can be driven by temperature, strain, electric field, magnetic field, light, etc., resulting in huge property coefficients, metal-insulator-transitions, electrical and optical control of magnetism, etc. The unparalleled variety of physical properties of oxides holds tremendous promise for electronic applications, but there is also a danger that oxides may become the immutable “material of the future” that never makes it into a real device.