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

"At the end of the day, success is the delivery of a scalable quantum computer," said Dr Chetan Nayak, Technical Fellow and Corporate Vice President, Quantum Hardware, Microsoft.

From BBC • Jun. 24, 2026

One of the new executive orders calls for the development of a quantum computer to “initiate the era of quantum-enabled scientific discovery.”

From MarketWatch • Jun. 23, 2026

IBM plans to spend an additional $9 billion over five years to develop Starling, a fault-tolerant quantum computer targeted for 2029.

From The Wall Street Journal • Jun. 23, 2026

The first order calls for development of “the first-ever quantum computer powerful enough for scientific research.”

From Barron's • Jun. 22, 2026

QMM reframes the universe as both a cosmic memory bank and a quantum computer.

From Science Daily • Jun. 18, 2026