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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
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Dissipation-Induced Order: The S=1/2 Quantum Spin Chain Coupled to an Ohmic Bath
Manuel Weber1, David J Luitz1,2, Fakher F Assaad3,4
1Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Str. 38, 01187 Dresden, Germany.
Physical Review Letters
|August 12, 2022
Summary
Coupling a quantum Heisenberg chain to a bosonic bath stabilizes long-range antiferromagnetic order, defying the Mermin-Wagner theorem. This quantum system
Area of Science:
- Condensed Matter Physics
- Quantum Many-Body Systems
- Quantum Information
Background:
- The Mermin-Wagner theorem prohibits long-range order in 1D quantum systems with continuous symmetries.
- Understanding symmetry breaking and order stabilization in low-dimensional quantum magnets is a key challenge.
Purpose of the Study:
- To investigate the effect of bosonic baths with ohmic dissipation on an S=1/2 antiferromagnetic quantum Heisenberg chain.
- To determine if bath coupling can overcome the Mermin-Wagner theorem and induce long-range order.
Main Methods:
- Large-scale, approximation-free quantum Monte Carlo simulations.
- Linear spin-wave theory analysis.
Main Results:
- Any finite coupling to an ohmic bath stabilizes long-range antiferromagnetic order.
- The bath's memory and retarded interactions are crucial for stabilizing this order.
- A crossover regime with distinct power-law behaviors in spin correlations emerges at small couplings.
Conclusions:
- Bosonic bath coupling can circumvent the Mermin-Wagner theorem in 1D quantum Heisenberg chains.
- The observed crossover phenomena have potential experimental relevance for quantum materials.
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