Finite-density massless two-color QCD at the isospin Roberge-Weiss point and the 't Hooft anomaly
Abstract
We study the phase diagram of two-flavor massless two-color QCD (QC2D ) under the presence of quark chemical potentials and imaginary isospin chemical potentials. At the special point of the imaginary isospin chemical potential, called the isospin Roberge-Weiss (RW) point, two-flavor QC2D enjoys the Z2 center symmetry that acts on both quark flavors and the Polyakov loop. We find a Z2 't Hooft anomaly of this system, which involves the Z2 center symmetry, the baryon-number symmetry, and the isospin chiral symmetry. Anomaly matching, therefore, constrains the possible phase diagram at any temperatures and quark chemical potentials at the isospin RW point, and we compare it with previous results obtained by chiral effective field theory and lattice simulations. We also point out an interesting similarity of two-flavor massless QC2D with (2 +1 )-dimensional quantum antiferromagnetic systems.
- Publication:
-
Physical Review Research
- Pub Date:
- August 2020
- DOI:
- 10.1103/PhysRevResearch.2.033253
- arXiv:
- arXiv:2005.13822
- Bibcode:
- 2020PhRvR...2c3253F
- Keywords:
-
- High Energy Physics - Theory;
- Condensed Matter - Strongly Correlated Electrons;
- High Energy Physics - Lattice;
- High Energy Physics - Phenomenology;
- Nuclear Theory
- E-Print:
- 23 pages, 2 figures, 2 appendices. v2: references are updated