qubit


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Related to qubit: Quantum computing

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).
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

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].
"When I joined Qubit in 2010, I was the company's first external hire during the research and development phase.
This means the design for a new Intel spin qubit chip could be dramatically scaled up.
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.
Yet making a single working qubit -- assuming Microsoft has indeed reached that point -- is only the first step.
Writing in a (https://www.nature.com/articles/nature24654) Nature paper Wednesday, titled "Observation of a many-body dynamical phase transition with a 53-qubit quantum simulator," researchers from University of Maryland and National Institute of Standards and Technology said: "As it becomes possible to exert more control over larger numbers of qubits, such simulators will be able to tackle a wider range of problems, such as materials design and molecular modelling, with the ultimate limit being a universal quantum computer that can solve general classes of hard problems3.
IBM's quantum computer in the United States has 16 qubits, meaning it can only perform basic calculations.
Google for example, had announced earlier that it's going to achieve quantum supremacy (creating a 50 qubit processor) by the end of 2017.
The third qubit was coupled to the reservoir and could measure the heat generated without mucking up the qubits of interest.
London-based start-up, Qubit, has sourced funding from a consortium led by Goldman Sachs (NYSE: GS).