Ultraviolet laser photoemission spectroscopy of FeSi: Observation of a gap opening in density of states

K. Ishizaka, T. Kiss, T. Shimojima, T. Yokoya, T. Togashi, S. Watanabe, C. Q. Zhang, C. T. Chen, Y. Onose, Y. Tokura, and S. Shin

Phys. Rev. B 72, 233202 – Published 16 December 2005

Abstract

The temperature $(T)$ dependent gap formation in the density of states (DOS) of FeSi has been investigated by angle-integrated laser photoemission spectroscopy (PES). With decreasing $T$ , the evolution of a small gap $(\sim 60 meV)$ at the Fermi level is observed in the DOS, indicating a $p$ -type semiconducting character of this compound. The Fermi edge, which has been controversial in all past PES studies, is extremely small at $5 K$ in accordance with transport and optical experiments. The $T$ dependence of the gap, which gets smeared out quickly at high $T$ as in optical conductivity spectrum, suggests the existence of a strong scattering mechanism beyond thermal excitations.

Received 6 October 2005

DOI:https://doi.org/10.1103/PhysRevB.72.233202

Authors & Affiliations

K. Ishizaka¹, T. Kiss², T. Shimojima¹, T. Yokoya³, T. Togashi⁴, S. Watanabe¹, C. Q. Zhang⁵, C. T. Chen⁵, Y. Onose⁶, Y. Tokura^6,7,8, and S. Shin^1,4

¹Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
²The Institute of Physical and Chemical Research (RIKEN), Wako, Saitama 351-0198, Japan
³The Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan
⁴The Institute of Physical and Chemical Research (RIKEN), Sayo-gun, Hyogo 679-5143, Japan
⁵Beijing Center for Crystal R&D, Chinese Academy of Science, Zhongguancun, Beijing 100080, China
⁶Spin Superstructure Project, ERATO, Japan Science and Technology Agency (JST), Tsukuba 305-8562, Japan
⁷Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
⁸Correlated Electron Research Center (CERC), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8562, Japan

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 72, Iss. 23 — 15 December 2005

Reuse & Permissions

Access Options

Author publication services for translation and copyediting assistance advertisement

Physical Review B

covering condensed matter and materials physics