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Title: Quantum critical electro-optic and piezo-electric nonlinearities
Although electro-optic (EO) nonlinearities are essential for many quantum and classical photonics applications, a major challenge is inefficient modulation in cryogenic environments. Guided by the connection between phase transitions and nonlinearity, we identify the quantum paraelectric perovskite SrTiO3as a strong cryogenic EO [>500 picometers per volt (pm/V)] and piezo-electric material (>90 picocoulombs per newton) atT= 5 K, at frequencies to at least 1 megahertz. Furthermore, by tuning SrTiO3toward quantum criticality, we more than double the EO and piezo-electric effects, demonstrating a linear Pockels coefficient above 1000 pm/V. Our results probe the link between quantum phase transitions, dielectric susceptibility, and nonlinearity, unlocking opportunities in cryogenic optical and mechanical systems and providing a framework for discovering new nonlinear materials.  more » « less
Award ID(s):
2317618
PAR ID:
10650385
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science
Date Published:
Journal Name:
Science
Volume:
390
Issue:
6771
ISSN:
0036-8075
Page Range / eLocation ID:
394 to 399
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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