PIRSA:17050081

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

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

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

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

Subir Sachdev

Harvard University

Talk number
PIRSA:17050081
Collection
Talk Type
Subject
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.