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Disorder Operator and Rényi Entanglement Entropy of Symmetric Mass Generation
Zi Hong Liu1, Yuan Da Liao2, Gaopei Pan2
1Institut für Theoretische Physik und Astrophysik and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, 97074 Würzburg, Germany.
Physical Review Letters
|April 29, 2024
Summary
Symmetric mass generation (SMG) is an unconventional quantum phase transition where Dirac fermions gap without symmetry breaking. Lattice quantum Monte Carlo simulations suggest SMG transitions correspond to unitary conformal field theories.
Area of Science:
- Condensed matter physics
- High energy theory
- Quantum field theory
Background:
- Symmetric mass generation (SMG) is a recently discovered quantum phase transition.
- It involves interacting Dirac fermions acquiring a gap without condensing a fermion bilinear mass term or breaking symmetry.
- This phenomenon lies beyond the conventional Gross-Neveu-Yukawa-Higgs paradigm.
Purpose of the Study:
- To investigate whether the SMG transition corresponds to a true unitary conformal field theory.
- To explore the nature of this unconventional quantum phase transition.
Main Methods:
- Utilizing large-scale lattice model quantum Monte Carlo simulations.
- Employing sharp diagnostic tools, including the scaling of the disorder operator.
- Analyzing Rényi entanglement entropy to characterize the transition.
Main Results:
- The simulations provide strong evidence suggesting the SMG transition is unconventional.
- Results indicate that the SMG transition aligns with the properties of a true (2+1)d unitary conformal field theory.
Conclusions:
- The SMG transition represents a novel type of quantum phase transition.
- The findings support the characterization of SMG transitions as unitary conformal field theories.
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