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Topological Spin Glass in Diluted Spin Ice
Arnab Sen1,2, R Moessner2
1Department of Theoretical Physics, Indian Association for the Cultivation of Science, Kolkata-700032, India.
Physical Review Letters
|July 22, 2015
Summary
Candidate spin liquid materials often freeze at low temperatures. This study reveals freezing and topological liquidity are inseparably linked, with disorder generating new degrees of freedom that freeze while the topological phase persists.
Area of Science:
- Condensed matter physics
- Quantum magnetism
- Topological phases of matter
Background:
- Many candidate spin liquid materials exhibit freezing as temperature decreases.
- Existing theories propose freezing is either intrinsic ("disorder-free glassiness") or extrinsic (coexisting with impurities).
Purpose of the Study:
- To investigate the relationship between freezing phenomena and topological liquidity in spin systems.
- To explore a potential third mechanism linking freezing and topological order.
Main Methods:
- Theoretical analysis of spin liquid models with disorder.
- Investigating the emergence of new degrees of freedom and their interactions.
- Examining the stability of the topological phase under these conditions.
Main Results:
- Demonstrated that freezing and topological liquidity can be inseparably linked.
- Showed that topological phases can generate novel degrees of freedom in response to disorder.
- These emergent degrees of freedom undergo a freezing transition, not the topological phase itself.
Conclusions:
- The observed freezing in spin liquid materials is not necessarily intrinsic disorder-free glassiness or extrinsic impurity freezing.
- A novel mechanism exists where the topological phase itself drives a freezing transition of emergent degrees of freedom.
- This finding offers a new perspective on the behavior of quantum spin liquids and related phenomena.
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