Editing Condensed matter physics (section)

===Cold atomic gases===
{{Main|Optical lattice}}

[[File:Bose Einstein condensate.png|thumb|left|The first [[Bose–Einstein condensate]] observed in a gas of ultracold [[rubidium]] atoms. The blue and white areas represent higher density.]]

[[Ultracold atom]] trapping in optical lattices is an experimental tool commonly used in condensed matter physics, and in [[atomic, molecular, and optical physics]]. The method involves using optical lasers to form an [[interference (wave propagation)|interference pattern]], which acts as a ''lattice'', in which ions or atoms can be placed at very low temperatures. Cold atoms in optical lattices are used as ''quantum simulators'', that is, they act as controllable systems that can model behavior of more complicated systems, such as [[Geometrical frustration|frustrated magnets]].<ref name=buluta-science2009>{{cite journal|last=Buluta|first=Iulia|author2=Nori, Franco|title=Quantum Simulators|journal=Science|year=2009|volume=326|issue=5949|doi=10.1126/science.1177838|bibcode= 2009Sci...326..108B|pages=108–11|pmid=19797653|s2cid=17187000}}</ref> In particular, they are used to engineer one-, two- and three-dimensional lattices for a [[Hubbard model]] with pre-specified parameters, and to study phase transitions for [[antiferromagnetism|antiferromagnetic]] and [[spin liquid]] ordering.<ref name=greiner-nature2008>{{cite journal |last=Greiner |first=Markus |author2=Fölling, Simon |title=Condensed-matter physics: Optical lattices |journal=Nature|year=2008|volume=453|pages=736–738|doi=10.1038/453736a|bibcode= 2008Natur.453..736G|issue=7196|pmid=18528388|s2cid=4572899 }}</ref><ref name=jaksch-aop2005>{{cite journal|last=Jaksch|first=D.|author2=Zoller, P. |title=The cold atom Hubbard toolbox|journal=Annals of Physics|year=2005|volume=315|issue=1|pages=52–79|doi=10.1016/j.aop.2004.09.010|arxiv= cond-mat/0410614 |bibcode= 2005AnPhy.315...52J|citeseerx=10.1.1.305.9031|s2cid=12352119}}</ref><ref name=":0" />

In 1995, a gas of [[rubidium]] atoms cooled down to a temperature of 170 [[Kelvin|nK]] was used to experimentally realize the [[Bose–Einstein condensate]], a novel state of matter originally predicted by [[S. N. Bose]] and [[Albert Einstein]], wherein a large number of atoms occupy one [[quantum state]].<ref name=nytimes-BEC>{{cite news|last=Glanz|first=James|title=3 Researchers Based in U.S. Win Nobel Prize in Physics|url=https://www.nytimes.com/2001/10/10/us/3-researchers-based-in-us-win-nobel-prize-in-physics.html|access-date=23 May 2012|newspaper=The New York Times|date=October 10, 2001}}</ref>