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arXiv · 2202.02269

Effects of intercomponent couplings on the appearance of time-reversal symmetry breaking fermion quadrupling state in two-component London models

Ilaria Maccari·Egor Babaev
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Abstract

A detection of bosonic metallic state that breaks the $Z_2$ time-reversal symmetry has been recently reported in Ba$_{1-x}$K$_x$Fe$_2$As$_2$ with a doping level $x \approx 0.8$. This is a metallic state of fermionic quadruplets that breaks time-reversal symmetry. As such, it has no condensate of Cooper pairs but has a long-range order between fermionic quartets. In the present manuscript, we investigate the emergence of this phase in a two-component London model via Monte Carlo simulations as a function of various intercomponent couplings.

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Ilaria Maccari, Egor Babaev. 2022-02-04. Effects of intercomponent couplings on the appearance of time-reversal symmetry breaking fermion quadrupling state in two-component London models. https://doi.org/10.1103/physrevb.105.214520

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