Unconventional Superconductivity in electron-doped layered metal nitride halides $M$N$X$ ($M$ = Ti, Zr, Hf; $X$ = Cl, Br, I)

Yuichi Kasahara; Kazuhiko Kuroki; Shoji Yamanaka; Yasujiro Taguchi

doi:10.1016/j.physc.2015.02.022

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arXiv · 1412.4447

Unconventional Superconductivity in electron-doped layered metal nitride halides $M$N$X$ ($M$ = Ti, Zr, Hf; $X$ = Cl, Br, I)

Yuichi Kasahara·Kazuhiko Kuroki·Shoji Yamanaka·Yasujiro Taguchi

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Abstract

In this review, we present a comprehensive overview of superconductivity in electron-doped metal nitride halides $M$N$X$ ($M$ = Ti, Zr, Hf; $X$ = Cl, Br, I) with layered crystal structure and two-dimensional electronic states. The parent compounds are band insulators with no discernible long-range ordered state. Upon doping tiny amount of electrons, superconductivity emerges with several anomalous features beyond the conventional electron-phonon mechanism, which stimulate theoretical investigations. We will discuss experimental and theoretical results reported thus far and compare the electron-doped layered nitride superconductors with other superconductors.

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Yuichi Kasahara, Kazuhiko Kuroki, Shoji Yamanaka, Yasujiro Taguchi. 2014-12-15. Unconventional Superconductivity in electron-doped layered metal nitride halides $M$N$X$ ($M$ = Ti, Zr, Hf; $X$ = Cl, Br, I). https://doi.org/10.1016/j.physc.2015.02.022

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