D-Wave Two (project code nameVesuvius) is the second commercially available quantum computer, and the successor to the first commercially available quantum computer, D-Wave One. Both computers were developed by Canadian company D-Wave Systems.[1] The computers are not general purpose, but rather are designed for quantum annealing. Specifically, the computers are designed to use quantum annealing to solve a single type of problem known as quadratic unconstrained binary optimization.[2] As of 2015, it was still debated whether large-scale entanglement takes place in D-Wave Two, and whether current or future generations of D-Wave computers will have any advantage over classical computers.[3][4][5][6][7][8][9]
Processor
D-Wave Two has a QPU (quantum processing unit) of 512 qubits—an improvement over the D-Wave One series' QPUs of about 128 qubits[10] The number of qubits can vary from chip to chip, due to variations in manufacturing.[11] The increase in qubit count for the D-Wave Two was accomplished by tiling qubit pattern of the D-Wave One. This pattern, named chimera by D-Wave Systems, has a limited connectivity such that a given qubit can only interact with at most six other qubits.[9] As with the D-Wave One, this restricted connectivity greatly limits the optimization problems that can be approached with the hardware.[11]
In July 2016, computer music researcher Alexis Kirke used a harmony algorithm developed for the D-Wave Two [22] live in a public musical performance for mezzo-soprano and electronics in the UK.[23][24]
In January 2021, a multi-institutional group of researches from ORNL, Purdue and D-Wave generated accurate results from materials science simulations on the DWave-2000Q processor that can be verified with neutron scattering experiments and other practical techniques.[25]