Materials scientists take control

Abstract

The discovery of a new way of controlling a class of complex-oxide materials, known as the Ruddlesden–Popper series of structures, may lead the way to making electronically tunable microwave devices. See Letter p.532 Tunable dielectric materials are valuable components for complex microwave circuitry, yet such materials tend to suffer losses when operated at microwave frequencies owing to intrinsic defects in their structures. Che-Hui Lee and colleagues have selected a family of dielectrics known to exhibit exceptionally low loss, and now show how these materials can be engineered to boost their tunability and attain levels of performance that rival all known tunable microwave dielectrics.