Photo by pluyar from unsplash
We develop a theory of superconducting pairing in low-density Strontium titanate due to quadratic coupling of electron density to soft transverse optical phonons [1]. It leads to static attractive potential… Click to show full abstract
We develop a theory of superconducting pairing in low-density Strontium titanate due to quadratic coupling of electron density to soft transverse optical phonons [1]. It leads to static attractive potential between electrons which decay length leff that scales inversely with soft optical gap ωT . For low electron densities n ≤ 1018cm−3 attraction between electrons is local and transition temperature Tc was found using Ref. [2]. The Tc(n) dependence in agreement with experimental data [3] for low doping was calculated. Next, we show that suppression of Tc by hydrostatic pressure [4] and strong increase of Tc due to isotop substitution O → O observed in [5] are explained within our theory.
Journal Title: Physical Review B
Year Published: 2021
Link to full text (if available)
Share on Social Media: Sign Up to like & get
recommendations!