Z_2 topological order near the Neel state of the square lattice antiferromagnet

APA

Sachdev, S. (2017). Z_2 topological order near the Neel state of the square lattice antiferromagnet. Perimeter Institute for Theoretical Physics. https://pirsa.org/17050081

MLA

Sachdev, Subir. Z_2 topological order near the Neel state of the square lattice antiferromagnet. Perimeter Institute for Theoretical Physics, May. 18, 2017, https://pirsa.org/17050081

BibTex

          @misc{ scivideos_PIRSA:17050081,
            doi = {10.48660/17050081},
            url = {https://pirsa.org/17050081},
            author = {Sachdev, Subir},
            keywords = {Quantum Matter},
            language = {en},
            title = {Z_2 topological order near the Neel state of the square lattice antiferromagnet},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2017},
            month = {may},
            note = {PIRSA:17050081 see, \url{https://scivideos.org/pirsa/17050081}}
          }
          

Subir Sachdev Harvard University

Source Repository PIRSA
Collection

Abstract

We classify quantum states proximate to the semiclassical Neel state of the spin S=1/2 square lattice antiferromagnet with two-spin near-neighbor and four-spin ring exchange interactions. Motivated by a number of recent experiments on the cuprates and the iridates, we examine states with Z_2 topological order, an order which is not present in the semiclassical limit. Some of the states break one or more of reflection, time-reversal, and lattice rotation symmetries, and can account for the observations. We discuss implications for the pseudogap phase.