Nonzero spontaneous electric polarization in metals: novel predictive methods and applications

Area of Science:

• Condensed Matter Physics
• Materials Science

Background:

• Ferroelectricity in metals, predicted by Anderson and Blount, has seen advancements since the discovery of LiOsO[Formula: see text].
• Experimental evaluation of spontaneous electric polarization (SEP) in LiOsO[Formula: see text] is challenging due to difficulties in electric field switching.
• Existing theoretical methods for SEP are limited to nonmetals, hindering the study of ferroelectric metals.

Purpose of the Study:

• To overcome theoretical limitations in calculating SEP for ferroelectric-like metals.
• To provide a robust theoretical framework for evaluating spontaneous electric polarization in LiOsO[Formula: see text].
• To confirm the coexistence of ferroelectricity and metallicity in LiOsO[Formula: see text].

Main Methods:

• Modification of Berry phase and Wannier functions approaches within density functional theory (DFT) and the modern theory of polarization.
• Application of these modified methods to calculate the SEP of LiOsO[Formula: see text].
• Validation of the calculated SEP through various predictive approaches.

Main Results:

• Successfully calculated the SEP of LiOsO[Formula: see text], finding it comparable to that of BaTiO[Formula: see text].
• Confirmed the coexistence of ferroelectricity and metallicity in LiOsO[Formula: see text].
• The developed theoretical approaches provide new insights into polarization properties.

Conclusions:

• This study resolves theoretical obstacles in evaluating SEP for ferroelectric metals.
• The findings complement experimental proposals like flexoelectricity and open new avenues for research in ferroelectric materials.
• The modified theoretical techniques are valuable for designing novel bio- and nano-ferroelectric-like metals.