Charge Friedel oscillations in a Mott insulator

When a metal undergoes a transition to an insulator it will lose its electronic Fermi surface. Interestingly, in some situations a “ghost” Fermi surface of electrically neutral spin carrying fermions may survive into the insulator. Such a novel ghost Fermi surface has been proposed to underlie the p...

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Bibliographic Details
Main Authors: Mross, David Fabian, Todadri, Senthil
Other Authors: Massachusetts Institute of Technology. Department of Physics
Format: Article
Language:en_US
Published: American Physical Society 2011
Online Access:http://hdl.handle.net/1721.1/67061
https://orcid.org/0000-0003-4203-4148
Description
Summary:When a metal undergoes a transition to an insulator it will lose its electronic Fermi surface. Interestingly, in some situations a “ghost” Fermi surface of electrically neutral spin carrying fermions may survive into the insulator. Such a novel ghost Fermi surface has been proposed to underlie the properties of a few different materials but its direct detection has proven elusive. In this paper, we show that the ghost Fermi surface leads to slowly decaying spatial oscillations of the electron density near impurities or other defects. These and related oscillations stem from the sharpness of the ghost Fermi surface and are direct analogs of the familiar Friedel oscillations in metals. The oscillation period contains geometric information about the shape of the ghost Fermi surface, which can be potentially exploited to detect its existence.