Large linear and nonlinear electro-optic coefficients in two-dimensional ferroelectrics

Zhijun Jiang (1, 2) , Charles Paillard (3, 1) , Hugh O H Churchill (1) , Minggang Xia (2) , Shengli Zhang (2) , Hongjun Xiang (4) , L. Bellaiche (1)

1 Institute for nanosciences and engineering and physics departement [University of Arkansas]
2 Xjtu - Xi'an Jiaotong University
3 SPMS - Laboratoire Structures, Propriétés et Modélisation des solides
4 Fudan University [Shanghai]

Analytical derivations and first-principles calculations are performed to investigate the electro-optic (EO) response of the two-dimensional ferroelectric SnS in its monolayer form. In addition to derive the formula for EO coefficients for two-dimensional systems, large linear and nonlinear electro-optic coefficients are discovered, along with a strongly nonlinear electro-optic response as a function of electric field. The origin of these electro-optic responses is further found and involves a few specific phonon modes, in general, and the evolution of their frequencies and atomic characteristics under electric fields, in particular. Large linear and nonlinear electro-optic coefficients can be found in other two-dimensional ferroelectrics, paving the way for potential optical device applications.

Domaines: Optique [physics.optics]

Zhijun Jiang, Charles Paillard, Hugh O H Churchill, Minggang Xia, Shengli Zhang, et al.. Large linear and nonlinear electro-optic coefficients in two-dimensional ferroelectrics. Physical Review B, 2022, 106 (8), pp.L081404. ⟨10.1103/PhysRevB.106.L081404⟩. ⟨hal-03767985⟩