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One approach to implementing continuous-variable quantum information protocols in the laboratory is through the techniques of [[quantum optics]].<ref name=":1" /><ref name=":2" /> By modeling each mode of the electromagnetic field as a [[quantum harmonic oscillator]] with its associated creation and annihilation operators, one defines a [[Conjugate variables|canonically conjugate]] pair of variables for each mode, the so-called "quadratures", which play the role of [[Position and momentum space|position and momentum]] observables. These observables establish a [[phase space]] on which [[Wigner quasiprobability distribution|Wigner quasiprobability distributions]] can be defined. [[Measurement in quantum mechanics|Quantum measurements]] on such a system can be performed using [[Homodyne detection|homodyne]] and [[Heterodyne detection|heterodyne detectors]].
[[Quantum teleportation]] of continuous-variable quantum information was achieved in 1998.<ref>{{Cite journal|last=Furusawa|first=A.|last2=Sørensen|first2=J. L.|last3=Braunstein|first3=S. L.|last4=Fuchs|first4=C. A.|last5=Kimble|first5=H. J.|last6=Polzik|first6=E. S.|date=1998-10-23|title=Unconditional Quantum Teleportation|url=http://science.sciencemag.org/content/282/5389/706|journal=Science|language=en|volume=282|issue=5389|pages=706–709|doi=10.1126/science.282.5389.706|issn=0036-8075|pmid=9784123}}</ref><ref>{{Cite journal|last=Braunstein|first=Samuel L.|last2=Fuchs|first2=Christopher A.|last3=Kimble|first3=H. J.|date=2000-02-01|title=Criteria for continuous-variable quantum teleportation|url=http://www.tandfonline.com/doi/abs/10.1080/09500340008244041|journal=Journal of Modern Optics|volume=47|issue=2-3|pages=267–278|arxiv=quant-ph/9910030|doi=10.1080/09500340008244041|issn=0950-0340|via=}}</ref> ([[Science (journal)|''Science'']] deemed this experiment one of the "top 10" advances of the year.<ref>{{Cite journal|last=|first=|date=1998-12-18|title=The Runners-Up: The News and Editorial Staffs|url=http://science.sciencemag.org/content/282/5397/2157|journal=Science|language=en|volume=282|issue=5397|pages=2157–2161|doi=10.1126/science.282.5397.2157|issn=0036-8075|via=}}</ref>) In 2013, quantum-optics techniques were used to create a "[[cluster state]]", a type of preparation of great interest to quantum computation, involving over 10,000 [[Quantum entanglement|entangled]] modes.<ref>{{Cite journal|last=Yokoyama|first=Shota|last2=Ukai|first2=Ryuji|last3=Armstrong|first3=Seiji C.|last4=Sornphiphatphong|first4=Chanond|last5=Kaji|first5=Toshiyuki|last6=Suzuki|first6=Shigenari|last7=Yoshikawa|first7=Jun-ichi|last8=Yonezawa|first8=Hidehiro|last9=Menicucci|first9=Nicolas C.|date=|title=Ultra-large-scale continuous-variable cluster states multiplexed in the time ___domain|url=http://www.nature.com/doifinder/10.1038/nphoton.2013.287|journal=Nature Photonics|volume=7|issue=12|pages=982–986|arxiv=1306.3366|doi=10.1038/nphoton.2013.287|via=}}</ref>
Another proposal is to modify the [[Trapped ion quantum computer|ion-trap quantum computer]]: instead of storing a single [[qubit]] in the internal energy levels of an ion, one could in principle use the position and momentum of the ion as continuous quantum variables.<ref>{{Cite journal|last=Ortiz-Gutiérrez|first=Luis|last2=Gabrielly|first2=Bruna|last3=Muñoz|first3=Luis F.|last4=Pereira|first4=Kainã T.|last5=Filgueiras|first5=Jefferson G.|last6=Villar|first6=Alessandro S.|date=2017-08-15|title=Continuous variables quantum computation over the vibrational modes of a single trapped ion|url=http://www.sciencedirect.com/science/article/pii/S0030401817302821|journal=Optics Communications|volume=397|pages=166–174|arxiv=1603.00065|doi=10.1016/j.optcom.2017.04.011|via=}}</ref>
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