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arXiv · 1706.04696

Rotation symmetry breaking in La2-xSrxCuO4 revealed by ARPES

E. Razzoli·C. E. Matt·Y. Sassa·M. Mansson·O. Tjernberg·G. Drachuck·M. Monomo·M. Oda·T. Kurosawa·Y. Huang·N. C. Plumb·M. Radovic·A. Keren·L. Patthey·J. Mesot·M. Shi
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Abstract

Using angle-resolved photoemission spectroscopy it is revealed that in the vicinity of optimal doping the electronic structure of La2-xSrxCuO4 cuprate undergoes an electronic reconstruction associated with a wave vector q_a=(pi, 0). The reconstructed Fermi surface and folded band are distinct to the shadow bands observed in BSCCO cuprates and in underdoped La2-xSrxCuO4 with x <= 0.12, which shift the primary band along the zone diagonal direction. Furthermore the folded bands appear only with q_a=(pi, 0) vector, but not with q_b= (0, pi). We demonstrate that the absence of q_b reconstruction is not due to the matrix-element effects in the photoemission process, which indicates the four-fold symmetry is broken in the system.

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E. Razzoli, C. E. Matt, Y. Sassa, M. Mansson, O. Tjernberg, G. Drachuck, M. Monomo, M. Oda, T. Kurosawa, Y. Huang, N. C. Plumb, M. Radovic, A. Keren, L. Patthey, J. Mesot, M. Shi. 2017-06-14. Rotation symmetry breaking in La2-xSrxCuO4 revealed by ARPES. https://doi.org/10.1103/physrevb.95.224504

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