Editing Matter wave (section)

==== Molecules ====
Recent experiments confirm the relations for molecules and even [[macromolecule]]s that otherwise might be supposed too large to undergo quantum mechanical effects. In 1999, a research team in [[Vienna]] demonstrated diffraction for molecules as large as [[fullerene]]s.<ref name="Arndt 680–682">{{cite journal| title=Wave–particle duality of C<sub>60</sub>| first=M.| last=Arndt| author2=O. Nairz |author3=J. Voss-Andreae |author3-link=Julian Voss-Andreae |author4=C. Keller |author5=G. van der Zouw |author6=A. Zeilinger |author6-link=Anton Zeilinger | journal=Nature| volume=401| issue=6754| pages=680–682|date=14 October 1999| pmid=18494170| doi=10.1038/44348| bibcode=1999Natur.401..680A| s2cid=4424892}}</ref> The researchers calculated a de Broglie wavelength of the most probable C<sub>60</sub> velocity as {{val|2.5|ul=pm}}.
More recent experiments prove the quantum nature of molecules made of 810 atoms and with a mass of {{val|10123|ul=Da}}.<ref>{{Cite journal |last1=Eibenberger|first1=Sandra |last2=Gerlich|first2=Stefan |last3=Arndt|first3=Markus |last4=Mayor|first4=Marcel |last5=Tüxen|first5=Jens |date=14 August 2013 |title=Matter–wave interference of particles selected from a molecular library with masses exceeding {{val|10000|u=amu}} |journal=Physical Chemistry Chemical Physics |language=en |volume=15|issue=35 |pages=14696–700 |doi=10.1039/c3cp51500a |pmid=23900710 |issn=1463-9084 |arxiv=1310.8343 |bibcode=2013PCCP...1514696E |s2cid=3944699 }}</ref> As of 2019, this has been pushed to molecules of {{val|25000|u=Da}}.<ref>{{Cite web |url=https://phys.org/news/2019-09-atoms-quantum-superposition.html |title=2000 atoms in two places at once: A new record in quantum superposition |website=phys.org |language=en-us |access-date=2019-09-25 }}</ref>

In these experiments the build-up of such interference patterns could be recorded in real time and with single molecule sensitivity.<ref name="Nano-20120325">{{cite journal |author=Juffmann, Thomas|title=Real-time single-molecule imaging of quantum interference |journal=Nature Nanotechnology |volume=7 |issue=5 |pages=297–300 |date=25 March 2012 |display-authors=etal|doi=10.1038/nnano.2012.34 |pmid=22447163 |arxiv=1402.1867 |bibcode=2012NatNa...7..297J |s2cid=5918772 }}</ref>
Large molecules are already so complex that they give experimental access to some aspects of the quantum-classical interface, i.e., to certain [[decoherence]] mechanisms.<ref>{{cite journal | first = Klaus | last = Hornberger | author2 = Stefan Uttenthaler | author3 = Björn Brezger | author4 = Lucia Hackermüller | author5 = Markus Arndt | author6 = Anton Zeilinger | year = 2003 | title = Observation of Collisional Decoherence in Interferometry | journal = Phys. Rev. Lett. | volume = 90 | pages = 160401 | doi = 10.1103/PhysRevLett.90.160401 | pmid = 12731960 | issue = 16 | bibcode = 2003PhRvL..90p0401H | arxiv = quant-ph/0303093 | s2cid = 31057272 }}</ref><ref>{{cite journal | first = Lucia | last = Hackermüller |author2=Klaus Hornberger |author3=Björn Brezger |author4=Anton Zeilinger |author5=Markus Arndt | year = 2004 | title = Decoherence of matter waves by thermal emission of radiation| journal = Nature | volume = 427 | pages = 711–714 | doi = 10.1038/nature02276 | pmid = 14973478 | issue = 6976 |arxiv = quant-ph/0402146 |bibcode = 2004Natur.427..711H | s2cid = 3482856 }}</ref>