quantum bit

American  

noun

Computers.

1. the fundamental unit of information in a quantum computer, capable of existing in two states, 0 or 1, simultaneously or at a different time.

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quantum bit Scientific  

1. The smallest unit of information in a quantum computer. Unlike bits in classical systems, which are in one of two possible states labelled 1 and 0, a quantum bit exists in a superposition of these two states, settling on one or the other only when a measurement of the state is made.

2. Also called qubit

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Etymology

Origin of quantum bit

First recorded in 1990–95

Example Sentences

These processors have been able to hold several hundred single-atom quantum systems up to now, whereby each atom represents one quantum bit or qubit as the basic unit of quantum information.

From Science Daily • Feb. 15, 2024

One alternative to the usual strategy is to increase the dimension of each quantum bit rather than trying to fit more qubits into the same space.

From Scientific American • Jan. 8, 2020

But superposition means that a quantum bit, or qubit, isn’t confined to being just 0 or 1.

From Washington Post • Oct. 23, 2019

Quantum computers work in a fundamentally different way from classical machines: a classical bit is either a 1 or a 0, but a quantum bit, or qubit, can exist in multiple states at once.

From Nature • Oct. 22, 2019

The systems are based on the notion of a “qubit,” or quantum bit — a basic value capable of encompassing more information than the 1’s and 0’s that are the basis of classical digital computing.

From New York Times • May 4, 2016