Related Experiment Video
Updated: Mar 8, 2026
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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Pseudocriticality in Antiferromagnetic Spin Chains
Sankalp Kumar1, Sumiran Pujari1,2, Jonathan D'Emidio3
1Indian Institute of Technology Bombay, Department of Physics, Mumbai, MH 400076, India.
Physical Review Letters
|March 6, 2026
Summary
This study explores deconfined criticality using an SU(N) model, revealing its proximity to complex conformal field theories (CFTs). Advanced simulations confirm predictions, even when CFTs enter the complex plane.
Area of Science:
- Condensed Matter Physics
- Quantum Field Theory
Background:
- Weak first-order pseudocriticality and approximate scale invariance are observed in various systems.
- Deconfined criticality in 2+1 dimensions is interpreted as slow flows near a complex conformal field theory (CFT).
Purpose of the Study:
- To investigate an SU(N) generalization of the Heisenberg antiferromagnet in 1+1 dimensions.
- To explore its proximity to a complex CFT as a function of N.
- To analyze the central charge and its relation to CFT predictions.
Main Methods:
- State-of-the-art quantum Monte Carlo simulations for continuous N.
- Improved loop estimator for Rényi entanglement entropy using a nonequilibrium work protocol.
Main Results:
- The SU(N) model in 1+1 dimensions is found to be near a complex CFT, tunable with N.
- Excellent agreement between simulation results and CFT predictions for the central charge was observed.
- The real part of the complex central charge was recovered with high accuracy for N>2, where the CFT is complex.
Conclusions:
- The dimerized phase of the spin-1 chain (equivalent to N=3) is pseudocritical and proximate to a complex CFT.
- This work provides new insights into the behavior of deconfined criticality and complex CFTs.
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