qubit

English

Alternative forms

• qbit

Etymology

Blend of quantum +‎ bit, influenced by cubit (“historical unit of length”). Coined by American physicist Benjamin Schumacher in 1995.

Pronunciation

• IPA^(key): /ˈkjuːbɪt/
• enPR: kyo͞o'bĭt, IPA^(key): /ˈkjubɪt/
• Homophone: cubit

Noun

qubit (plural qubits)

1. (computing) A quantum bit; the basic unit of quantum information described by a superposition of two states; a quantum bit in a quantum computer capable of being in a state of superposition.

   Synonyms: qbit, quantum bit

   Coordinate term: bit

   • 2012, ‘An uncertain future’, The Economist, 25 Feb 2012:

     Each extra qubit in a quantum machine doubles the number of simultaneous operations it can perform.

   • 2019 October 21, Dennis Overbye, “Quantum Computing Is Coming, Bit by Qubit”, in New York Times‎^[1]:

     Google’s Sycamore computer has all of 53 qubits to its name, as does a new IBM computer, installed online at the company’s Quantum Computation Center in Poughkeepsie, N.Y. System One, IBM’s black cube from tomorrow, only has 20 qubits.

   • 2019 October 23, Cade Metz, “Google Claims a Quantum Breakthrough That Could Change Computing”, in New York Times‎^[2]:

     By harnessing that odd behavior, scientists can instead build a quantum bit, or qubit, which stores a combination of 1 and 0. Two qubits can hold four values at once. And as the number of qubits grows, a quantum computer becomes exponentially more powerful.

Derived terms

• multiqubit

Related terms

• qumix
• quregister
• qutrit
• qudit

Translations

quantum bit

• Chinese:

  Mandarin: 量子位元 (liàngzǐ wèiyuán)

• Esperanto: kvantumbito
• Finnish: kubitti (fi)
• French: qubit (fr) m
• (deprecated template usage) {{trans-mid}}
• German: Qubit (de) n
• Icelandic: skammtabiti m
• Italian: qubit (it) m
• Japanese: 量子ビット (りょうしビット, ryōshi bitto)
• Portuguese: qubit m
• Spanish: cúbit (es) m

See also

• nat, ban

Further reading

• qubit on Wikipedia.Wikipedia

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Portuguese

Noun

qubit m (plural s)

1. (computing) qubit (quantum bit)