Enhanced Cryogenic Piezoelectric and Electrooptic Nonlinearities with Materials Engineering

Cryogenic optics and mechanics are of critical importance for a variety of quantum applications and devices in extreme environments. Previously, we had discovered that SrTiO3 (STO) displays the largest Pockel’s effect at cryogenic temperatures to-date. In this talk, I will update our progress with this material. First, I will discuss measurements of the cryogenic piezoelectric response of STO. Our results show a response that exceeds lithium niobate by over an order of magnitude and addresses open questions about the cryogenic piezoelectric response of STO in previous work. I will then present our most recent efforts on engineering the ferroelectric-paraelectric phase transition of STO. As a result of this control, we show more than a doubling of the electrooptical and piezoelectric responses, which match with theoretical predictions.