# Quantum annealing with manufactured spins

@article{Johnson2011QuantumAW, title={Quantum annealing with manufactured spins}, author={M. William Johnson and Mohammed Amin and S. Gildert and Trevor Lanting and Firas Hamze and Neil G. Dickson and R. Harris and Andrew J. Berkley and J. Johansson and Paul I. Bunyk and E. M. Chapple and C Enderud and Jeremy P. Hilton and Kamran Karimi and Eric Ladizinsky and Nicolas Ladizinsky and Travis Oh and I. G. Perminov and Chris Rich and Murray C. Thom and Elena Tolkacheva and C. J. S. Truncik and Sergey Uchaikin and Jianyu Wang and Blake A. Wilson and Geordie Rose}, journal={Nature}, year={2011}, volume={473}, pages={194-198} }

Many interesting but practically intractable problems can be reduced to that of finding the ground state of a system of interacting spins; however, finding such a ground state remains computationally difficult. It is believed that the ground state of some naturally occurring spin systems can be effectively attained through a process called quantum annealing. If it could be harnessed, quantum annealing might improve on known methods for solving certain types of problem. However, physical…

## 1,003 Citations

Quantum physics: Keep your feet on the ground

- Physics, MedicineNature
- 2011

Johnson et al. use quantum annealing to find the ground state of an artificial Ising spin system comprised of an array of eight superconducting flux qubits with programmable spin–spin couplings.

Quantum versus classical annealing of Ising spin glasses

- Physics, MedicineScience
- 2015

The question of when quantum speedup may be expected is revisited and it is shown that the results depend on how the problem is described and how the optimization routine is implemented, which implies that care must be taken when using QMC simulations to assess the potential for quantum speed up.

Thermally assisted quantum annealing of a 16-qubit problem.

- Physics, MedicineNature communications
- 2013

It is experimentally demonstrated that, even with annealing times eight orders of magnitude longer than the predicted single-qubit decoherence time, the probabilities of performing a successful computation are similar to those expected for a fully coherent system.

Experimental signature of programmable quantum annealing.

- Physics, MedicineNature communications
- 2013

This experiment uses groups of eight superconducting flux qubits with programmable spin-spin couplings, embedded on a commercially available chip with >100 functional qubits, and suggests that programmable quantum devices, scalable with currentsuperconducting technology, implement quantum annealing with a surprising robustness against noise and imperfections.

Quantum annealing using vacuum states as effective excited states of driven systems

- 2020

Quantum annealing, which is particularly useful for combinatorial optimization, becomes more powerful by using excited states, in addition to ground states. However, such excited-state quantum…

Multiqubit Tunneling and Evolution in Quantum Annealing

- Physics
- 2018

Author(s): Brady, Lucas | Advisor(s): van Dam, Wim | Abstract: Quantum computing seeks to use the powers of quantum mechanics to accomplish tasks that classical computers cannot easily accomplish.…

Demonstration of a Nonstoquastic Hamiltonian in Coupled Superconducting Flux Qubits

- Physics, Mathematics
- 2019

Quantum annealing (QA) is a heuristic algorithm for finding low-energy configurations of a system, with applications in optimization, machine learning, and quantum simulation. Up to now, all…

Readiness of Quantum Optimization Machines for Industrial Applications

- Physics, MathematicsPhysical Review Applied
- 2019

Although the results show that transverse-field quantum annealing is outperformed by state-of-the-art classical optimization algorithms, these benchmark instances are hard and small in the size of the input, therefore representing the first industrial application ideally suited for testing near-term Quantum annealers and other quantum algorithmic strategies for optimization problems.

Practical engineering of hard spin-glass instances

- Physics
- 2016

Recent technological developments in the field of experimental quantum annealing have made prototypical annealing optimizers with hundreds of qubits commercially available. The experimental…

Proposed Experiments to Test the Foundations of Quantum Computing

- Mathematics
- 2016

Quantum computing promises computational performance that is exponentially faster than any conceivable classical computer. This is due to the theoretically expected scaling of N entangled qubits,…

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