qubit

[′kyü·bit]

(computer science)

In quantum computation, a superposition of the ground state and the excited state of an elementary two-level quantum system (such as a two-level atom or a nuclear spin), corresponding to a classical bit that is either 0 (corresponding to the ground state) or 1 (corresponding to the excited state).

qubit

(QUantum BIT) A unit of computation in a quantum computer. The "bit" in qubit is somewhat misleading, although when a qubit is read, it does collapse into a 0 or 1. However, for computation and prior to being observed, the qubit can be in a superposition state, which means multiple states at the same time measured by electron motion and direction.

Unlike classical bits, qubits are not used for storage. Data are transferred to the qubits for computation and then read out for answers. Rather than a charge or pulse of electricity in a bit, it is the electrons in the qubit that are manipulated based on the laws of quantum mechanics.

In addition, while a classical bit is made of transistors, there are different qubit designs and constructions. See quantum computing.

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References in periodicals archive

Another ongoing approach in developing quantum computers consists in using topological qubits within which the operations to be performed upon are safeguarded due to a microscopically incorporated topological symmetry that allows the qubit to correct the errors that may arise during the computing process [1].

FROM BITS TO QUBITS, FROM COMPUTING TO QUANTUM COMPUTING: AN EVOLUTION ON THE VERGE OF A REVOLUTION IN THE COMPUTING LANDSCAPE

The state of the qubits was rewound back to its original starting point.

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"When I joined Qubit in 2010, I was the company's first external hire during the research and development phase.

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This means the design for a new Intel spin qubit chip could be dramatically scaled up.

INTEL TESTS SMALLEST SPIN QUBIT' CHIP FOR QUANTUM

That seems to be shifting now, with a cascade of advances, not only in building the quantum bits but also in quantum memory devices and processes to link the qubits together into a working computer.

Quantum Computing Moves Toward Reality

Yet making a single working qubit -- assuming Microsoft has indeed reached that point -- is only the first step.

Microsoft, Google prepare for big leaps in quantum computing

IBM's quantum computer in the United States has 16 qubits, meaning it can only perform basic calculations.

Australia researchers say find new way to build quantum computers

Google for example, had announced earlier that it's going to achieve quantum supremacy (creating a 50 qubit processor) by the end of 2017.

IBM announced a 17 qubit quantum processor, its fastest ever

The third qubit was coupled to the reservoir and could measure the heat generated without mucking up the qubits of interest.

Even quantum information is physical: erasing qubits emits heat, as predicted by Landauer's principle

London-based start-up, Qubit, has sourced funding from a consortium led by Goldman Sachs (NYSE: GS).

Qubit raises funding