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Title: Modeling temperature, frequency, and strain effects on the linear electro-optic coefficients of ferroelectric oxides
An electro-optic modulator offers the function of modulating the propagation of light in a material with an electric field and enables a seamless connection between electronics-based computing and photonics-based communication. The search for materials with large electro-optic coefficients and low optical loss is critical to increase the efficiency and minimize the size of electro-optic devices. We present a semi-empirical method to compute the electro-optic coefficients of ferroelectric materials by combining first-principles density-functional theory calculations with Landau–Devonshire phenomenological modeling. We apply the method to study the electro-optic constants, also called Pockels coefficients, of three paradigmatic ferroelectric oxides: BaTiO 3 , LiNbO 3 , and LiTaO 3 . We present their temperature-, frequency-, and strain-dependent electro-optic tensors calculated using our method. The predicted electro-optic constants agree with the experimental results, where available, and provide benchmarks for experimental verification.  more » « less
Award ID(s):
1806147 1931610 2122070 2122071
PAR ID:
10322566
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Journal of Applied Physics
Volume:
131
Issue:
16
ISSN:
0021-8979
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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