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arXiv · 2108.03246

Signatures of a Majorana-Fermi surface in the Kitaev magnet Ag$_3$LiIr$_2$O$_6$

Joshuah T. Heath·Faranak Bahrami·Sangyun Lee·Roman Movshovich·Xiao Chen·Fazel Tafti·Kevin S. Bedell
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Abstract

Detecting Majorana fermions in experimental realizations of the Kitaev honeycomb model is often complicated by non-trivial interactions inherent to potential spin liquid candidates. In this work, we identify several distinct thermodynamic signatures of massive, itinerant Majorana fermions within the well-established analytical paradigm of Landau-Fermi liquid theory. We find a qualitative and quantitative agreement between the salient features of our Landau-Majorana liquid theory and the Kitaev spin liquid candidate Ag$_3$LiIr$_2$O$_6$. Our study presents strong evidence for a Fermi liquid-like ground state in the fundamental excitations of a honeycomb iridate, and opens new experimental avenues to detect itinerant Majorana fermions in condensed matter systems.

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Joshuah T. Heath, Faranak Bahrami, Sangyun Lee, Roman Movshovich, Xiao Chen, Fazel Tafti, Kevin S. Bedell. 2021-08-06. Signatures of a Majorana-Fermi surface in the Kitaev magnet Ag$_3$LiIr$_2$O$_6$. https://doi.org/10.1038/s42005-023-01403-w

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