Strain engineering of optoelectronic and ferroelectric properties in R3-phase Zn₃TeO₆: a first-principles study

A systematic evaluation of the optoelectronic properties of ferroelectric ternary oxides under strain is essential for their integration into functional devices. In this study, the R3-phase ternary oxide Zn₃TeO₆ was investigated using density functional theory to examine its stability, electronic structure, optical properties, ferroelectric behavior, and carrier mobility under both compressive and tensile strain. Calculations of elastic constants, molecular dynamics simulations, and phonon spectra confirm the stability of Zn₃TeO₆ within a modest strain range. Compressive strain increases phonon frequencies, elastic constants, and bandgap, while enhancing ferroelectric polarization. In contrast, tensile strain decreases the bandgap and promotes visible-light absorption. Carrier transport analysis reveals pronounced n-type conduction, with electron mobility reaching ∼150 cm² V^-1 s^-1, further enhanced under compressive strain due to the suppression of polar optical phonon and piezoelectric scattering. These findings demonstrate that strain engineering offers an effective approach to tuning the multifunctional properties of R3-Zn₃TeO₆, highlighting its potential for ferroelectric and photovoltaic applications.