Welcome to D-Wave¶
I’m not happy with all the analyses that go with just the classical theory, because Nature isn’t classical, dammit, and if you want to make a simulation of nature, you’d better make it quantum mechanical, and by golly it’s a wonderful problem, because it doesn’t look so easy.
It’s not a Turing machine, but a machine of a different kind.
—Richard Feynman, 1981
|||Feynman, Richard P. “Simulating physics with computers.” International Journal of Theoretical Physics 21, no. 6 (1982): 467-488.|
What We Do¶
Despite the incredible power of today’s supercomputers, many complex computing problems cannot be addressed by conventional systems. The huge growth of data and our need to better understand everything from the universe to our own DNA leads us to seek new tools that can help provide answers. Quantum computing is the next frontier in computing, providing an entirely new approach to solving the world’s most difficult problems.
While certainly not easy, much progress has been made in the field of quantum computing since 1981, when Feynman gave his famous lecture at the California Institute of Technology. Still a relatively young field, quantum computing is complex and different approaches are being pursued around the world. Today, there are two leading candidate architectures for quantum computers: gate model and quantum annealing. In gate-model quantum computing, the aim is to control and manipulate the evolution of the quantum states over time—a difficult challenge, especially at large scales, because quantum systems are incredibly delicate.
At D-Wave, our approach is quantum annealing, which harnesses the natural evolution of quantum states: we initialize the system in a delocalized state, we gradually turn on the description of the problem we wish to solve, and quantum physics allows the system to follow these changes. The configuration at the end corresponds to the answer we are trying to find. Quantum annealing is implemented in D-Wave systems as a single quantum algorithm, and this scalable approach to quantum computing has enabled us to create quantum processing units (QPUs) with more than 2000 quantum bits (qubits)—far beyond the state of the art for gate-model quantum computing.
D-Wave has been developing various generations of our “machine of a different kind,” to use Feynman’s words, since 1999. We are the world’s first commercial quantum computer company.
Introducing the D-Wave System¶
This section describes the system at a high level. For more details on the physical system, for a description of customer roles, and for essential safety information required for anyone who accesses the physical system, see the D-Wave Quantum Computer Operations manual, which is available from D-Wave.
The D-Wave system contains a QPU that must be must be kept at a temperature near absolute zero and isolated from the surrounding environment in order to behave quantum mechanically. The system achieves these requirements as follows:
- Cryogenic temperatures, achieved using a closed-loop cryogenic dilution refrigerator system. The QPU operates at temperatures below 15 mK.
- Shielding from electromagnetic interference, achieved using a radio frequency (RF)–shielded enclosure and a magnetic shielding subsystem.
Quantum Processing Unit¶
The D-Wave QPU (Figure 2) is a lattice of tiny metal loops, each of which is a qubit or a coupler. Below temperatures of 9.2 kelvin, these loops become superconductors and exhibit quantum-mechanical effects.
The D-Wave 2000Q QPU has up to 2048 qubits and 6016 couplers. To reach this scale, it uses 128,000 Josephson junctions, which makes the D-Wave 2000Q QPU by far the most complex superconducting integrated circuit ever built.
For details on the topology of the QPU, see the D-Wave QPU Architecture: Chimera section.
D-Wave Software Environment¶
Users interact with the D-Wave quantum computer through a web user interface (UI), and through client libraries that communicate with the Solver API (SAPI). The SAPI components are responsible for user interaction, user authentication, and work scheduling. In turn, SAPI connects to back-end servers that send problems to and return results from the QPU via quantum machine instructions and that (optionally) run postprocessing algorithms on results. See Figure 3 for a simplified view of the D-Wave software environment.
|||In the D-Wave system, a solver is simply a resource that runs a problem. Some solvers interface to the QPU; others leverage CPU and GPU resources.|
D-Wave clients make it easier to code applications across various platforms. They communicate with the SAPI web services component using the REST/HTTPS protocol and allow you to:
- Query available solvers and solver properties
- Submit problems
- Cancel previously submitted problems
- Retrieve problem status
- Fetch results if successful
- Retrieve errors if unsuccessful
D-Wave clients use a traditional request/response paradigm, where the application code runs on a client system, and the client commands are translated to REST/HTTP calls and then transmitted to the server. See Solver API REST Web Services Developer Guide for details.
D-Wave’s suite of open-source software tools, Ocean, makes application development for quantum computers more rapid and efficient. Available on GitHub, these tools facilitate collaborative projects that can leverage quantum computing system resources. See https://github.com/dwavesystems to access the Ocean SDK, and https://docs.ocean.dwavesys.com for the associated documentation.
Leap Quantum Application Environment¶
Leap is the real-time Quantum Application Environment from D-Wave Systems Inc.
Leap brings quantum computing to the real world by providing cloud access to our systems, for free, to anyone who wants to give it a try. Through Leap, you can learn about the types of problems that the D-Wave quantum computer can solve, run interactive demos and coding examples that actually submit problems to the quantum computer, access Ocean (our open-source software tools) and contribute your coding ideas, and join the growing conversation in our community of like-minded users.
Sign up for Leap here: https://cloud.dwavesys.com/leap.