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Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
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Quantum fluctuations drive nonmonotonic correlations in a qubit lattice
Alejandro Lopez-Bezanilla1, Andrew D King2, Cristiano Nisoli3
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, 87545, NM, USA. alejandrolb@gmail.com.
Nature Communications
|January 18, 2024
Summary
Low uncertainty can surprisingly promote order in magnetic systems affected by thermal and quantum fluctuations. Experiments on superconducting qubits reveal how controlled disorder and quantum effects lead to novel ordered phases.
Area of Science:
- Quantum Computing
- Condensed Matter Physics
- Statistical Mechanics
Background:
- Fluctuations can disrupt order in systems, increasing entropy.
- Magnetic systems with disorder can exhibit complex ordering behaviors due to fluctuations.
- Quantum annealers are effective simulators for programmable spin systems.
Purpose of the Study:
- To investigate how controlled uncertainty influences ordering in systems with thermal and quantum fluctuations.
- To explore the 'order-by-disorder' phenomenon using quantum simulation.
- To demonstrate the creation of specific ordered phases in a controlled quantum system.
Main Methods:
- Utilized programmable superconducting qubits as a quantum annealer platform.
- Designed experiments on a triangular lattice of interacting qubits.
- Precisely controlled disorder, effective temperature, and quantum fluctuations.
Main Results:
- Demonstrated the creation of ordered ferrimagnetic and layered anisotropic disordered phases.
- Observed that a low level of uncertainty promotes ordering.
- Provided evidence for quantum fluctuations lowering system energy via entropy increase and defect clustering.
Conclusions:
- Quantum fluctuations and controlled disorder can lead to emergent ordering phenomena.
- The study provides insights into defect and fluctuation dynamics in quantum devices.
- Findings may help reduce costs in quantum information processing.
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