Dependence on the interlayer spacing of nanoscale electronic states in layered nitride chloride superconductors α-Mx TiNCl investigated by scanning tunneling microscopy/spectroscopy

Автор(и)

  • Akira Sugimoto Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8521, Japan https://orcid.org/0000-0002-5265-3017
  • Takumi Nishi Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8521, Japan
  • Toshikazu Ekino Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8521, Japan https://orcid.org/0000-0002-6855-091X
  • Masashi Tanaka Department of Basic Science, Kyushu Institute of Technology, Kitakyushu 804-8550, Japan https://orcid.org/0000-0002-4323-5999
  • Alexander M. Gabovich Institute of Physics, National Academy of Sciences of Ukraine, Kyiv 03028, Ukraine

DOI (Low Temperature Physics):


https://doi.org/10.1063/10.0046917

Ключові слова:

layered nitride chloride superconductors, tunnel spectroscopy, pseudogap, canning tunneling microscopy/spectroscopy

Анотація

We studied the influence of interlayer spacing on the nanoscale electronic states of layered nitride chloride superconductors α-MxTiNCl (M = pyridine (Py), Na, K) using scanning tunneling microscopy and spectroscopy. It was shown that these materials exhibit a strong decrease in the critical temperature (Tc) with increasing inter-layer spacing d. Our measurements revealed gap-like features in differential conductance spectra that remain nearly independent of Tc and d. The extracted characteristic gap energy Eg shows spatial inhomogeneity on nanometer scales and does not follow the conventional Bardeen–Cooper–Schrieffer scaling. These observations suggest that the detected gap-like feature is more consistent with pseudogap-like behavior, most probably related to other electronic properties, than with true superconducting pairing. It is similar to the situation in cuprate high-temperature superconductors, where pseudogap is a prominent feature. The results suggest the importance of the local electronic structure and doping effects in determining superconducting properties of layered systems.

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Опубліковано

2026-09-28

Як цитувати

(1)
Akira Sugimoto, Takumi Nishi, Toshikazu Ekino, Masashi Tanaka, and Alexander M. Gabovich, Dependence on the interlayer spacing of nanoscale electronic states in layered nitride chloride superconductors α-Mx TiNCl investigated by scanning tunneling microscopy/spectroscopy, Low Temp. Phys. 52, 1384–1389, (2026) [Fiz. Nyzk. Temp. 52, 1535–1540, (2026)] DOI: https://doi.org/10.1063/10.0046917.

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Том 52 № 11 (2026)

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