First-principles design and subsequent synthesis of a material to search for the permanent electric dipole moment of the electron

TL;DR

This paper reports the first-principles design and experimental synthesis of a new ferroelectric material, Eu$_{0.5}$Ba$_{0.5}$TiO$_3$, optimized for detecting the electron's permanent electric dipole moment.

Contribution

It introduces a computationally guided approach to designing a specific material for fundamental physics experiments, combining theory and synthesis.

Findings

Eu$_{0.5}$Ba$_{0.5}$TiO$_3$ exhibits large ferroelectric polarization.

The material shows pressure-dependent ferroelectric properties.

No magnetic ordering observed at liquid helium temperature.

Abstract

We describe the first-principles design and subsequent synthesis of a new material with the specific functionalities required for a solid-state-based search for the permanent electric dipole moment of the electron. We show computationally that perovskite-structure europium barium titanate should exhibit the required large and pressure-dependent ferroelectric polarization, local magnetic moments, and absence of magnetic ordering even at liquid helium temperature. Subsequent synthesis and characterization of Eu$_{0.5}$Ba$_{0.5}$TiO$_3$ ceramics confirm the predicted desirable properties.