Work

Fractionalization in a square-lattice model with time-reversal symmetry

Year: 2008

Type: article

Abstract: We propose a two-dimensional time-reversal invariant system of essentially noninteracting electrons on a square lattice that exhibits configurations with fractional charges $\ifmmode\pm\else\textpm\fi{}e∕2$. These are vortexlike topological defects in the dimerization order parameter describing spatial modulation in the electron hopping amplitudes. Charge fractionalization is established by a simple counting argument, analytical calculation within the effective low-energy theory, and by an exact numerical diagonalization of the lattice Hamiltonian. We comment on the exchange statistics of fractional charges and possible realizations of the system.

Source: Physical Review B

DOI: 10.1103/physrevb.77.033104

Authors: B. Seradjeh, C. Weeks, M. Franz

Institutions: University of British Columbia, University of California, Santa Barbara, Kavli Institute for Theoretical Physics

Language: English

Topic: Topological Materials and Phenomena

Subfield: Condensed Matter Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: National Science Foundation, Killam Trusts, Natural Sciences and Engineering Research Council of Canada, Kavli Institute for Theoretical Physics, University of California, Santa Barbara

Award: G5905734738