quantum computer

American  

noun

1. a computer that makes use of the quantum states of electrons or other particles to store and process information as quantum bits.

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quantum computer British  

noun

1. a type of computer which uses the ability of quantum systems to be in many different states at once, thus allowing it to perform many different computations simultaneously

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quantum computer Scientific  

1. A computer that exploits the quantum mechanical properties of superposition in order to allow a single operation to act on a large number of pieces of data. In a quantum computer, the data to be manipulated, represented in quantum bits, exists in all possible states simultaneously, in superposition. This allows a single operation to operate over all of these states at once, in contrast with a classical computer, which must carry out an operation for each state separately. Because of the difficulty of creating environments small enough for quantum effects to emerge but sufficiently isolated to prevent interaction with outside influences such as heat, only extremely rudimentary quantum computers currently exist, though algorithms for possible future devices are being developed.

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Other Word Forms

• quantum computing
  noun

Etymology

Origin of quantum computer

First recorded in 1980–85

Example Sentences

See Examples For:

quantum computer

Over the summer, the president signed executive orders pushing for building a powerful quantum computer and protecting the government against related cyber threats.

From The Wall Street Journal ● Oct. 12, 2026

The Pasadena, Calif., company is focused on building a large-scale, fault-tolerant, error-corrected quantum computer it says will deliver on the commercial promises of quantum computing.

From The Wall Street Journal ● Oct. 8, 2026

IBM and Lockheed Martin team up to deploy a quantum computer at a new tech hub in Switzerland.

From Barron's ● Sep. 10, 2026

IBM has said its goal is to build a fault-tolerant quantum computer by the end of the decade.

From MarketWatch ● Sep. 8, 2026

Eventually, checking the answer can itself become infeasible unless researchers make strong assumptions about how the quantum computer behaves internally.

From Science Daily ● Aug. 30, 2026