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arXiv · 1312.1757

Observation of well-defined quasi-particle over a wide energy range in quasi-2D system

L. -L. Jia·Z. -H. Liu·Y. -P. Cai·T. Qian·X. -P. Wang·H. Miao·P. Richard·Y. -G. Zhao·Y. Li·M. Shi·H. Ding·D. -M. Wang·J. -B. He·G. -F. Chen·S. -C. Wang
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Abstract

We report the observation by angle-resolved photoemission spectroscopy measurements of a highly anisotropic Dirac-cone structure in high quality SrMnBi2 crystals. We reveal a well-defined sharp quasi-particle, linearly dispersive with $v_{F_1}/v_{F_2}\sim$ 5--6, forming a hole-like anisotropic Dirac-cone. The density of states for the cone remains linear up to as high as ~650 meV of binding energy. The scattering rate of the quasi-particle (QP) increases linearly as function of binding energy, indicating a non-Fermi-Liquid behavior. Our results suggest the existence of a dilute two-dimensional electron gas system in this three-dimensional material.

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L. -L. Jia, Z. -H. Liu, Y. -P. Cai, T. Qian, X. -P. Wang, H. Miao, P. Richard, Y. -G. Zhao, Y. Li, M. Shi, H. Ding, D. -M. Wang, J. -B. He, G. -F. Chen, S. -C. Wang. 2013-12-06. Observation of well-defined quasi-particle over a wide energy range in quasi-2D system. https://doi.org/10.1103/physrevb.90.035133

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