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arXiv · 1809.08972

Probing spin correlations using angle resolved photoemission in a coupled metallic/Mott insulator system

V. Sunko·F. Mazzola·S. Kitamura·S. Khim·P. Kushwaha·O. J. Clark·M. Watson·I. Markovic·D. Biswas·L. Pourovskii·T. K. Kim·T. -L. Lee·P. K. Thakur·H. Rosner·A. Georges·R. Moessner·T. Oka·A. P. Mackenzie·P. D. C. King
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Abstract

A nearly free electron metal and a Mott insulating state can be thought of as opposite ends of possibilities for the motion of electrons in a solid. In the magnetic oxide metal PdCrO$_{2}$, these two coexist as alternating layers. Using angle resolved photoemission, we surprisingly find sharp band-like features in the one-electron removal spectral function of the correlated subsystem. We show that these arise because a hole created in the Mott layer moves to and propagates in the metallic layer while retaining memory of the Mott layer's magnetism. This picture is quantitatively supported by a strong coupling analysis capturing the physics of PdCrO$_{2}$ in terms of a Kondo lattice Hamiltonian. Our findings open new routes to use the non-magnetic probe of photoemission to gain insights into the spin-susceptibility of correlated electron systems.

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V. Sunko, F. Mazzola, S. Kitamura, S. Khim, P. Kushwaha, O. J. Clark, M. Watson, I. Markovic, D. Biswas, L. Pourovskii, T. K. Kim, T. -L. Lee, P. K. Thakur, H. Rosner, A. Georges, R. Moessner, T. Oka, A. P. Mackenzie, P. D. C. King. 2018-09-24. Probing spin correlations using angle resolved photoemission in a coupled metallic/Mott insulator system. https://doi.org/10.1126/sciadv.aaz0611

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