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Stable algebraic spin liquid in a Hubbard model
S R Hassan1, P V Sriluckshmy, Sandeep K Goyal
1The Institute of Mathematical Sciences, CIT Campus, Chennai, India.
Physical Review Letters
|February 5, 2013
Summary
We discovered a stable algebraic spin liquid (ASL) phase in a novel Hubbard model. This phase, protected by time-reversal symmetry, is realizable in cold atom experiments.
Area of Science:
- Condensed matter physics
- Quantum magnetism
- Many-body systems
Background:
- Algebraic spin liquid (ASL) phases are exotic states of matter with potential applications in quantum computing.
- Understanding the conditions for realizing and stabilizing ASL phases is a key challenge in condensed matter physics.
Purpose of the Study:
- To investigate the existence and stability of an algebraic spin liquid (ASL) phase in a Hubbard model on a honeycomb lattice.
- To identify potential experimental realizations and observable signatures of this ASL phase.
Main Methods:
- Utilizing a Hubbard model with spin-dependent hopping on a honeycomb lattice.
- Analyzing the model under conditions of large on-site repulsion to derive an effective spin model.
- Proving the time-reversal invariance of the effective spin model within the Mott phase.
Main Results:
- Demonstrated the existence of a stable algebraic spin liquid (ASL) phase.
- Identified the effective spin model as the Kitaev model, with gapless Majorana fermions protected by time-reversal invariance.
- Established the time-reversal invariance of the effective spin model throughout the Mott phase, ensuring ASL stability.
Conclusions:
- The proposed Hubbard model provides a viable route to realizing a stable algebraic spin liquid (ASL).
- The findings suggest that cold atom systems are suitable platforms for experimentally observing this ASL phase.
- Proposed specific experimental signals to detect the ASL state, facilitating future research.
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