Optimized Methodology for the Calculation of Electrostriction from First‐Principles

Abstract

In this work a new method for the calculation of the electrostrictive properties of materials using density functional theory is presented. The method relies on the thermodynamical equivalence, in a dielectric, of the quadratic mechanical responses (stress or strain) to applied electric stimulus (electric or polarization fields) to the strain or stress dependence of its dielectric susceptibility or stiffness tensors. Comparing with current finite‐field methodologies for the calculation of electrostriction, it is demonstrated that this presented methodology offers significant advantages of efficiency, robustness, and ease of use. These advantages render tractable the high throughput theoretical investigation into the largely unknown electrostrictive properties of materials, and the microscopic origins of giant electrostriction.

Divergent electrostriction at ferroelectric phase transitions: example of strain-induced ferroelectiricty in KTaO3

“…To proceed, we note that while one may consider electrostriction as the "strain/stress induced quadratically by an electric/polarisation field", one may also view it as the theromodynamically equivalent "linear change in susceptibility/inverse susceptibility induced by a stress or a strain" [9,10] shown below:…”

“…In our previous work [10], we outlined the advantages of this method of calculation, amongst which are greater computational efficiency and robustness. Viewed from the perspective of Eqs.…”

“…[13] We note that obtaining the electrostriction tensors in this manner using eq.1 and finite differences, will yield an "improper" electrostriction tensor containing contributions described by Nelson and Lax [14]; the "proper" tensor may be obtained from this by the addition of permitivity components to certain electrostriction components. [10,14] As a test case, we will analyse the electrostrictive response at the strain-induced FEPT present in KTaO 3 . KTaO 3 is a highly suitable material for such a study as it is an incipient ferroelectric which undergoes a ferroelectric phase transition due to relatively small axial stress.…”

“…It also circumvents issues associated with applying an electric field to the paraelectric phase of a perovskite [34], and more general shortcomings associated with finite field methodologies [10].…”

Time-dependent theory of optical electro- and magnetostriction

“…Experimental studies of electrostriction have also revealed interesting phenomena, such as the giant electrostriction [15][16][17][18][19][20][21][22][23][24][25], negative electrostriction [26,27], and deformations of liquid crystals [28,29] and biological cells [30]. On the theoretical side, electrostriction has also been under extensive study [31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48].…”