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Quantum annealing with manufactured spins
M W Johnson1, M H S Amin, S Gildert
1D-Wave Systems Inc., 100-4401 Still Creek Drive, Burnaby, British Columbia V5C 6G9, Canada. mwjohnson@dwavesys.com
Nature
|May 13, 2011
Summary
Researchers demonstrate quantum annealing on an artificial spin system to find ground states. This programmable system offers a new approach for solving complex optimization problems.
Area of Science:
- Quantum Computing
- Condensed Matter Physics
- Computational Science
Background:
- Finding the ground state of interacting spin systems is computationally challenging.
- Quantum annealing is a promising method for solving such problems, but physical implementations are limited.
- Current research is primarily focused on microscopic spins in condensed-matter systems.
Purpose of the Study:
- To utilize quantum annealing for finding the ground state of an artificial Ising spin system.
- To demonstrate a programmable artificial spin network for studying spin systems.
- To bridge the gap between theoretical models and experimental investigations of spin networks.
Main Methods:
- Employed quantum annealing on an array of eight superconducting flux quantum bits.
- Configured programmable spin-spin couplings to create diverse spin networks.
- Monitored system dynamics to observe the transition to low-energy configurations.
Main Results:
- Successfully found the ground state of the artificial Ising spin system.
- Observed a distinct signature of quantum annealing, differentiating it from classical thermal annealing.
- Demonstrated the system's ability to be reconfigured in situ for various spin network topologies.
Conclusions:
- The programmable artificial spin network serves as a practical physical system for quantum annealing.
- This approach may lead to more effective solutions for hard combinatorial optimization problems.
- Scaling this system could enable the implementation of practical quantum algorithms.
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