Abstract
Electron-doped TiNCl is a superconductor, for which exotic mechanisms of the superconductivity have been discussed. However, difficulty in preparing large single-phase samples has prevented the direct observation of its electronic structure and how that changes with electron doping. In this study, micro-photoemission spectroscopy (µ-PES) was used to reveal the electronic structures of TiNCl and Na-intercalated TiNCl (Na-TiNCl). Comparison of Ti 2p core-level spectra shows the enhancement of a spectral feature in Na-TiNCl that suggests an increase in its metallic character. This indicates the introduction of electron carriers to the TiNCl layers. Although the overall valence band electronic structure of parent TiNCl could be reproduced by first-principle calculations, that of Na-TiNCl showed a marked deviation from the rigid band model near the Fermi level (EF). The spectral shape observed near EF of Na-TiNCl was found to be similar to a result in early transition metal oxides that has been attributed to the effect of strong electron correlation. The present study also demonstrated the usefulness of µ-PES to obtain reliable electronic structure data for samples that are difficult to make at large sizes.
| Original language | English |
|---|---|
| Article number | 104709 |
| Journal | Journal of the Physical Society of Japan |
| Volume | 88 |
| Issue number | 10 |
| DOIs | |
| Publication status | Published - Jan 1 2019 |
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ASJC Scopus subject areas
- Physics and Astronomy(all)
Cite this
µ-PES Studies on TiNCl and Quasi-two-dimensional Superconductor Na-intercalated TiNCl. / Kataoka, Noriyuki; Terashima, Kensei; Tanaka, Masashi; Hosoda, Wataru; Taniguchi, Takumi; Wakita, Takanori; Muraoka, Yuji; Yokoya, Takayoshi.
In: Journal of the Physical Society of Japan, Vol. 88, No. 10, 104709, 01.01.2019.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - µ-PES Studies on TiNCl and Quasi-two-dimensional Superconductor Na-intercalated TiNCl
AU - Kataoka, Noriyuki
AU - Terashima, Kensei
AU - Tanaka, Masashi
AU - Hosoda, Wataru
AU - Taniguchi, Takumi
AU - Wakita, Takanori
AU - Muraoka, Yuji
AU - Yokoya, Takayoshi
PY - 2019/1/1
Y1 - 2019/1/1
N2 - Electron-doped TiNCl is a superconductor, for which exotic mechanisms of the superconductivity have been discussed. However, difficulty in preparing large single-phase samples has prevented the direct observation of its electronic structure and how that changes with electron doping. In this study, micro-photoemission spectroscopy (µ-PES) was used to reveal the electronic structures of TiNCl and Na-intercalated TiNCl (Na-TiNCl). Comparison of Ti 2p core-level spectra shows the enhancement of a spectral feature in Na-TiNCl that suggests an increase in its metallic character. This indicates the introduction of electron carriers to the TiNCl layers. Although the overall valence band electronic structure of parent TiNCl could be reproduced by first-principle calculations, that of Na-TiNCl showed a marked deviation from the rigid band model near the Fermi level (EF). The spectral shape observed near EF of Na-TiNCl was found to be similar to a result in early transition metal oxides that has been attributed to the effect of strong electron correlation. The present study also demonstrated the usefulness of µ-PES to obtain reliable electronic structure data for samples that are difficult to make at large sizes.
AB - Electron-doped TiNCl is a superconductor, for which exotic mechanisms of the superconductivity have been discussed. However, difficulty in preparing large single-phase samples has prevented the direct observation of its electronic structure and how that changes with electron doping. In this study, micro-photoemission spectroscopy (µ-PES) was used to reveal the electronic structures of TiNCl and Na-intercalated TiNCl (Na-TiNCl). Comparison of Ti 2p core-level spectra shows the enhancement of a spectral feature in Na-TiNCl that suggests an increase in its metallic character. This indicates the introduction of electron carriers to the TiNCl layers. Although the overall valence band electronic structure of parent TiNCl could be reproduced by first-principle calculations, that of Na-TiNCl showed a marked deviation from the rigid band model near the Fermi level (EF). The spectral shape observed near EF of Na-TiNCl was found to be similar to a result in early transition metal oxides that has been attributed to the effect of strong electron correlation. The present study also demonstrated the usefulness of µ-PES to obtain reliable electronic structure data for samples that are difficult to make at large sizes.
UR - http://www.scopus.com/inward/record.url?scp=85072712166&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85072712166&partnerID=8YFLogxK
U2 - 10.7566/JPSJ.88.104709
DO - 10.7566/JPSJ.88.104709
M3 - Article
AN - SCOPUS:85072712166
VL - 88
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 10
M1 - 104709
ER -