Editing Low-temperature technology timeline (section)

== 20th century ==
* 1905 – [[Carl von Linde]] obtains pure liquid [[oxygen]] and [[nitrogen]].
* 1906 – [[Willis Carrier]] patents the basis for modern [[air conditioning]].
* 1908 – [[Heike Kamerlingh Onnes]] liquifies [[helium]].
* 1911 – Heike Kamerlingh Onnes discloses his research on metallic low-temperature phenomenon characterised by no electrical resistance, calling it [[superconductivity]].
* 1915 – [[Wolfgang Gaede]] – the [[Diffusion pump]]
* 1920 – Edmund Copeland and Harry Edwards use [[iso-butane]] in small refrigerators.
* 1922 – [[Baltzar von Platen (inventor)|Baltzar von Platen]] and [[Carl Munters]] invent the 3 fluids absorption chiller, exclusively driven by heat.
* 1924 – [[Fernand Holweck]] – the [[Holweck pump]]
* 1926 – [[Albert Einstein]] and [[Leó Szilárd]] invent the [[Einstein refrigerator]].
* 1926 – [[Willem Hendrik Keesom]] solidifies helium.
* 1926 – [[General Electric Company]] introduced the first hermetic compressor refrigerator
* 1929 – David Forbes Keith of Toronto, Ontario, Canada received a patent for the [[Icy Ball]] which helped hundreds of thousands of families through the [[Dirty Thirties]].
* 1933 – [[William Giauque]] and others – Adiabatic demagnetization refrigeration
* 1937 – [[Pyotr Leonidovich Kapitsa]], [[John F. Allen (physicist)|John F. Allen]], and [[Don Misener]] discover [[superfluidity]] using helium-4 at 2.2 [[Kelvin|K]]
* 1937 – [[Frans Michel Penning]] invents a type of [[cold cathode]] vacuum gauge known as [[Penning gauge]]
* 1944 – [[Manne Siegbahn]], the [[Turbomolecular pump|Siegbahn pump]]
* 1949 – S.G. Sydoriak, E.R. Grilly, E.F. Hammel, first measurements on pure 3He in the 1 K range
* 1950 –  Invention of the so-called Gifford-McMahon cooler by K.W. Taconis (patent US2,567,454)
* 1951 – [[Heinz London]] invents the principle of the [[dilution refrigerator]]
* 1955 – Willi Becker <!-- April 28, 2011 – Removed link to politician; no article yet for this pump engineer. --> [[turbomolecular pump]] concept<ref>[http://www.avs.org/pdf/timelineD.pdf Vacuum Science & Technology Timeline]</ref>
* 1956 – G.K. Walters, W.M. Fairbank, discovery of phase separation in 3He-4He mixtures
* 1957 – Lewis D. Hall, Robert L. Jepsen and John C. Helmer [[Ion pump (physics)|ion pump]] based on Penning discharge
* 1959 – [[Kleemenko cycle]]
* 1960 – Reinvention of the Gifford-McMahon cooler by H.O. McMahon and W.E. Gifford
* 1965 – D.O. Edwards, and others, discovery of finite solubility of 3He in 4He at 0K
* 1965 – P. Das, R. de Bruyn Ouboter, K.W. Taconis, one-shot dilution refrigerator<ref>{{Cite journal | doi = 10.1016/j.cryogenics.2021.103390| issn=0011-2275 | title = Development of Dilution refrigerators – A review | journal = Cryogenics| volume = 121| year = 2022| last1 = Zu | first1 = H.| last2 = Dai | first2 = W.| last3 = de Waele | first3 = A.T.A.M.| s2cid=244005391 }}</ref>
* 1966 – H.E. Hall, P.J. Ford, K. Thomson, continuous dilution refrigerator
* 1972 – [[David Lee (physicist)|David Lee]], [[Robert Coleman Richardson]] and [[Douglas Osheroff]] discover superfluidity in helium-3 at 0.002 K.
* 1973 – [[Linear compressor]]
* 1978 – [[Laser cooling]] demonstrated in the groups of Wineland and Dehmelt.
* 1983 – Orifice-type [[pulse tube refrigerator]] invented by Mikulin, Tarasov, and Shkrebyonock
* 1986 – [[Karl Alexander Müller]] and [[J. Georg Bednorz]] discover [[high-temperature superconductivity]]
* 1995 – [[Eric Cornell]] and [[Carl Wieman]] create the first<ref>{{cite web|title=New State of Matter Seen Near Absolute Zero|url=http://physics.nist.gov/News/Update/950724.html|publisher=NIST|url-status=dead|archive-url=https://web.archive.org/web/20100601175245/http://physics.nist.gov/News/Update/950724.html|archive-date=2010-06-01}}</ref> [[Bose–Einstein condensate]], using a dilute gas of [[Rubidium-87]] cooled to 170 nK. They won the Nobel Prize for Physics in 2001 for BEC.
* 1999 – D.J. Cousins and others, dilution refrigerator reaching 1.75 mK
* 1999 – The current world record lowest temperature was set at 100 picokelvins (pK), or 0.000 000 000 1 of a kelvin, by cooling the nuclear spins in a piece of [[rhodium]] metal.<ref>{{cite web|url = http://ltl.tkk.fi/wiki/LTL/World_record_in_low_temperatures|title = World record in low temperatures|access-date =2009-05-05| archive-url= https://web.archive.org/web/20090618075820/http://ltl.tkk.fi/wiki/LTL/World_record_in_low_temperatures| archive-date=2009-06-18| url-status= live}}</ref>