Gauging Quantum States

Autor(en)

Jutho Haegeman, Karel Van Acoleyen, Norbert Schuch, J. Ignacio Cirac, Frank Verstraete

Abstrakt

We present an operational procedure to transform global symmetries into local symmetries at the level of individual quantum states, as opposed to typical gauging prescriptions for Hamiltonians or Lagrangians. We then construct a compatible gauging map for operators, which preserves locality and reproduces the minimal coupling scheme for simple operators. By combining this construction with the formalism of projected entangled-pair states (PEPS), we can show that an injective PEPS for the matter fields is gauged into a G-injective PEPS for the combined gauge-matter system, which potentially has topological order. We derive the corresponding parent Hamiltonian, which is a frustration-free gauge-theory Hamiltonian closely related to the Kogut-Susskind Hamiltonian at zero coupling constant. We can then introduce gauge dynamics at finite values of the coupling constant by applying a local filtering operation. This scheme results in a low-parameter family of gauge-invariant states of which we can accurately probe the phase diagram, as we illustrate by studying a Z(2) gauge theory with Higgs matter.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Ghent University , Rheinisch-Westfälische Technische Hochschule Aachen, Max-Planck-Institut für Quantenoptik

Journal

Physical Review X

Band

5

Anzahl der Seiten

10

ISSN

2160-3308

DOI

https://doi.org/10.1103/PhysRevX.5.011024

Publikationsdatum

02-2015

Peer-reviewed

Ja

ÖFOS 2012

103025 Quantenmechanik

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/fafc340b-384e-4e4d-a2f1-dddb79ab5ea7