**CG**: *n*

**CT**: **Quantum bits**, or qubits, can hold quantum information much longer now thanks to efforts by an international research team. The researchers have increased the retention time, or coherence time, to 10 milliseconds—10,000 times longer than the previous record—by combining the orbital motion and spinning inside an atom. Such a boost in information retention has major implications for information technology developments since the longer coherence time makes spin-orbit qubits the ideal candidate for building large quantum computers.

**S**: Phys.org – https://phys.org/news/2020-09-technology-quantum-bits-longer-previous.html (last access: 10 December 2020)

**N**: 1. – quantum (*n*): 1610s, “one’s share or portion,” from Latin *quantum* (plural *quanta*) “as much as, so much as; how much? how far? how great an extent?” neuter singular of correlative pronominal adjective *quantus* “as much”. Introduced in physics directly from Latin by Max Planck, 1900; reinforced by Einstein, 1905. *Quantum theory* is from 1912; *quantum mechanics*, 1922; *quantum jump* is first recorded 1954; *quantum leap*, 1963, often figurative.

– bit (*n*): computerese word, 1948 abbreviation coined by U.S. computer pioneer John W. Tukey (1915-2000) of binary digit, probably chosen for its identity with *bit* (“small piece,” c. 1200; related Old English *bite* “act of biting,” and *bita* “piece bitten off,” probably are the source of the modern words meaning “boring-piece of a drill” (1590s), “mouthpiece of a horse’s bridle” (mid-14c.), and “a piece bitten off, morsel” (c. 1000).).

2. A quantum bit (or qubit) is the quantum mechanical analogue of a classical bit. In classical computing the information is encoded in bits, where each bit can have the value zero or one. In quantum computing the information is encoded in qubits.

3. Several different physical implementations of qubits are possible. A number of examples are the polarizations of a photon, two of the (multiple) discrete energy levels of an ion, a superconducting Transmon qubit, the nuclear spin states of an atom or the spin states of an electron. Quantum Inspire is designed to control different qubit technologies. Its modular design allows it to re-use components that are technology independent while replacing components (software and hardware) that are technology dependent.

4. Short for quantum bit, a qubit is similar to the classical computer bit, but where a bit is represented as a 0 or a 1, or “on” or “off”, a qubit can be either or both at the same time. It is the qubit’s versatility that allows it to perform efficient calculations at rates exponentially greater than current computer processes.

**S**: 1. OED – https://www.etymonline.com/word/bit; https://www.etymonline.com/search?q=quantum+bit+++ (last access: 10 December 2020). 2&3. QI – https://www.quantum-inspire.com/kbase/what-is-a-qubit/ (last access: 10 December 2020).

**SYN**: qubit (*n*), qbit (*less frequent*).

**S**: TERMIUM PLUS – https://www.btb.termiumplus.gc.ca/tpv2alpha/alpha-eng.html?lang=eng&i=1&index=esr&srchtxt=QUBIT (last access: 10 December 2020)

**CR**: bit, computer science, nanotechnology, quantum computer.