Meng Cheng

About

Meng Cheng is a theoretical physicist in the Department of Physics at Yale University. His research focuses on quantum condensed matter theory, with a particular emphasis on the classification and characterization of exotic quantum phases of matter. As a condensed matter theorist, he contributes to advancing the understanding of complex quantum systems and their unique properties.

Research topics

• Quantum mechanics
• Physics
• Mathematics
• Statistical physics
• Geometry
• Computer Science
• Algorithm
• Theoretical physics
• Mathematical analysis
• Statistics

Selected publications

• Lieb-Schultz-Mattis, Luttinger, and 't Hooft - anomaly matching in lattice systems

  SciPost Physics · 2023 · 107 citations

  1st authorCorresponding

  We analyze lattice Hamiltonian systems whose global symmetries have ’t Hooft anomalies. As is common in the study of anomalies, they are probed by coupling the system to classical background gauge fields. For flat fields (vanishing field strength), the nonzero spatial components of the gauge fields can be thought of as twisted boundary conditions, or equivalently, as topological defects. The symmetries of the twisted Hilbert space and their representations capture the anomalies. We demonstrate t…

  DOI

• Measuring Rényi entanglement entropy with high efficiency and precision in quantum Monte Carlo simulations

  npj Quantum Materials · 2022 · 63 citations

  Abstract We develop a nonequilibrium increment method in quantum Monte Carlo simulations to obtain the Rényi entanglement entropy of various quantum many-body systems with high efficiency and precision. To demonstrate its power, we show the results on a few important yet difficult (2 + 1) d quantum lattice models, ranging from the Heisenberg quantum antiferromagnet with spontaneous symmetry breaking, the quantum critical point with O(3) conformal field theory (CFT) to the toric code $${{\mathbb{…

  DOI

• Strong-to-Weak Spontaneous Symmetry Breaking in Mixed Quantum States

  PRX Quantum · 2025-03-06 · 60 citations

  articleOpen access

  Symmetry in mixed quantum states can manifest in two distinct forms: , where each individual pure state in the quantum ensemble is symmetric with the same charge, and , which applies only to the entire ensemble. This paper explores a novel type of spontaneous symmetry breaking (SSB) where a strong symmetry is broken to a weak one. While the SSB of a weak symmetry is measured by the long-ranged two-point correlation function, the strong-to-weak SSB (SWSSB) is measured by the . We prove that SWSSB…

  PublisherOA PDFDOI

• Scaling of the disorder operator at deconfined quantum criticality

  SciPost Physics · 2022 · 55 citations

  We study scaling behavior of the disorder parameter, defined as the expectation value of a symmetry transformation applied to a finite region, at the deconfined quantum critical point in (2+1)d in the J-Q_3 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow> <mml:mi>J</mml:mi> <mml:mo>−</mml:mo> <mml:msub> <mml:mi>Q</mml:mi> <mml:mn>3</mml:mn> </mml:msub> </mml:mrow> </mml:math> model via large-scale quantum Monte Carlo simulations. We show that the disorder par…

  DOI

• Toward a Classification of Mixed-State Topological Orders in Two Dimensions

  PRX Quantum · 2025-01-21 · 46 citations

  articleOpen accessSenior author

  The classification and characterization of topological phases of matter is well understood for ground states of gapped Hamiltonians that are well isolated from the environment. However, decoherence due to interactions with the environment is inevitable—thus motivating the investigation of topological orders in the context of mixed states. Here, we take a step toward classifying mixed-state topological orders in two spatial dimensions by considering their (emergent) generalized symmetries. We arg…

  PublisherOA PDFDOI

Recent grants

• CAREER: Interplay of Symmetry and Topology in Condensed Matter Systems

  NSF · $500k · 2019–2024

Frequent coauthors

• Youfang Sun

  Chinese Academy of Sciences

  56 shared

• Yuyang Zhang

  Central South University

  56 shared

• Jiansheng Lian

  South China Sea Institute Of Oceanology

  56 shared

• Lei Jiang

  University of Hong Kong

  56 shared

• Lintao Huang

  South China Sea Institute Of Oceanology

  52 shared

• Xiaolei Yu

  University of Hong Kong

  52 shared

• Yong Luo

  46 shared

• Xinming Lei

  University of Hong Kong

  36 shared

Awards & honors

• NSF CAREER award (2019)
• Alfred P. Sloan Foundation Research Fellowship (2019)

Similar researchers at Yale University

• Steven Girvinh-103
• Helen Cainesh-76
• Charles Ahnh-65