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arXiv · 0910.0158

Pressure-driven phase transitions in correlated systems

Yu-Zhong Zhang·Ingo Opahle·Harald O. Jeschke·Roser Valenti
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Abstract

Motivated by recent experimental measurements on pressure-driven phase transitions in Mott-insulators as well as the new iron pnictide superconductors, we show that first principles Car-Parrinello molecular dynamics calculations are a powerful method to describe the microscopic origin of such transitions. We present results for (i) the pressure-induced insulator to metal phase transition in the prototypical Mott insulator TiOCl as well as (ii) the pressure-induced structural and magnetic phase transitions in the family of correlated metals $A$Fe$_2$As$_2$ ($A$=Ca,Sr,Ba). Comparison of our predictions with existing experimental results yields very good agreement.

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Yu-Zhong Zhang, Ingo Opahle, Harald O. Jeschke, Roser Valenti. 2009-10-01. Pressure-driven phase transitions in correlated systems. https://doi.org/10.1088/0953-8984%2F22%2F16%2F164208

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