Editing Matter wave (section)

==== Neutrons ====
{{Also| Neutron diffraction}}
[[Neutron]]s, produced in [[nuclear reactors]] with kinetic energy of around {{val|1|u=MeV}}, [[Neutron temperature#Thermal|thermalize]] to around {{val|0.025|u=eV}} as they scatter from light atoms. The resulting de&nbsp;Broglie wavelength (around {{val|180|ul=pm}}) matches interatomic spacing and neutrons scatter strongly from hydrogen atoms. Consequently, neutron matter waves are used in [[crystallography]], especially for biological materials.<ref>{{Cite journal |last1=Blakeley |first1=Matthew P |last2=Langan |first2=Paul |last3=Niimura |first3=Nobuo |last4=Podjarny |first4=Alberto |date=2008-10-01 |title=Neutron crystallography: opportunities, challenges, and limitations |journal=Current Opinion in Structural Biology |series=Carbohydrates and glycoconjugates / Biophysical methods |volume=18 |issue=5 |pages=593–600 |doi=10.1016/j.sbi.2008.06.009 |issn=0959-440X |pmc=2586829 |pmid=18656544}}</ref> Neutrons were discovered in the early 1930s, and their diffraction was observed in 1936.<ref>{{Cite journal |last1=Mason |first1=T. E. |last2=Gawne |first2=T. J. |last3=Nagler |first3=S. E. |last4=Nestor |first4=M. B. |last5=Carpenter |first5=J. M. |date=2013-01-01 |title=The early development of neutron diffraction: science in the wings of the Manhattan Project |url=https://journals.iucr.org/a/issues/2013/01/00/wl5168/index.html |journal=Acta Crystallographica Section A: Foundations of Crystallography |language=en |volume=69 |issue=1 |pages=37–44 |doi=10.1107/S0108767312036021 |issn=0108-7673 |pmc=3526866 |pmid=23250059}}</ref> In 1944, [[Ernest O. Wollan]], with a background in X-ray scattering from his PhD work<ref name=PhysicsTodayObit>
{{cite journal
 |last1=Snell |first1=A. H.
 |last2=Wilkinson |first2=M. K.
 |last3=Koehler |first3=W. C.
 |year=1984
 |title=Ernest Omar Wollan
 |journal=[[Physics Today]]
 |volume=37 |issue=11 |page=120
 |bibcode=1984PhT....37k.120S
 |doi=10.1063/1.2915947
 |doi-access=free
}}</ref> under [[Arthur Compton]], recognized the potential for applying thermal neutrons from the newly operational [[X-10 Graphite Reactor|X-10 nuclear reactor]] to [[crystallography]]. Joined by [[Clifford G. Shull]], they developed<ref>
{{cite book
 |last=Shull |first=C. G.
 |date=1997
 |chapter=Early Development of Neutron Scattering
 |chapter-url=https://www.nobelprize.org/nobel_prizes/physics/laureates/1994/shull-lecture.pdf
 |archive-url=https://web.archive.org/web/20170519024556/https://www.nobelprize.org/nobel_prizes/physics/laureates/1994/shull-lecture.pdf
 |archive-date=2017-05-19
 |editor-last=Ekspong |editor-first=G.
 |title=Nobel Lectures, Physics 1991–1995
 |pages=145–154
 |publisher=[[World Scientific Publishing]]
}}</ref> [[neutron diffraction]] throughout the 1940s. 
In the 1970s, a [[neutron interferometer]] demonstrated the action of [[gravity]] in relation to wave–particle duality.<ref>{{Cite journal |doi = 10.1103/PhysRevLett.34.1472|title = Observation of Gravitationally Induced Quantum Interference |url=https://www.rpi.edu/dept/phys/Courses/PHYS6510/PhysRevLett.34.1472.pdf |year = 1975|last1 = Colella|first1 = R.|last2 = Overhauser|first2 = A. W.|last3 = Werner|first3 = S. A.|journal = Physical Review Letters|volume = 34|issue = 23|pages = 1472–1474|bibcode = 1975PhRvL..34.1472C}}</ref> The double-slit experiment was performed using neutrons in 1988.<ref>{{Cite journal |last1=Zeilinger |first1=Anton |last2=Gähler |first2=Roland |last3=Shull |first3=C. G. |last4=Treimer |first4=Wolfgang |last5=Mampe |first5=Walter |date=1988-10-01 |title=Single- and double-slit diffraction of neutrons |url=https://journals.aps.org/rmp/abstract/10.1103/RevModPhys.60.1067 |journal=Reviews of Modern Physics |volume=60 |issue=4 |pages=1067–1073 |doi=10.1103/RevModPhys.60.1067|bibcode=1988RvMP...60.1067Z }}</ref>