{{Short description|German physicist and professor}} {{BLP primary sources|date=July 2023}} {{Infobox scientist | image = Gerhard-rempe 2016-10-13.jpg | caption = Rempe in 2016 | birth_date = {{Birth date and age|1956|4|22|df=y}} | birth_place = Bottrop, Germany | fields = Quantum optics | workplaces = Max Planck Institute of Quantum Optics<br />Technical University of Munich | alma_mater = LMU Munich }} '''Gerhard Rempe''' (born 22 April 1956) is a German physicist, Director at the Max Planck Institute of Quantum Optics and Honorary Professor at the Technical University of Munich. He has performed pioneering experiments in atomic and molecular physics, quantum optics and quantum information processing.
== Career == {{BLP unreferenced section|date=July 2023}} Gerhard Rempe studied mathematics and physics at the University of Duisburg-Essen and LMU Munich between 1976 and 1982. In 1986, he received his PhD degree at LMU. The thesis was entitled "investigation of the interaction of Rydberg atoms with radiation" and reports on experiments performed in the group of Herbert Walther. In the same year he was awarded a first job offer to a permanent position as a lecturer at Vrije Universiteit Amsterdam in the Netherlands. Rempe remained in Munich and completed his habilitation in 1990 with the thesis "Quantum effects in the one-atom maser". From 1990 to 1991, he was Lecturer and from 1990 to 1992 Robert Andrews Millikan Fellow at the California Institute of Technology in Pasadena, California, US, working with H. Jeff Kimble. In 1992, he accepted an appointment as professor of experimental physics at the University of Konstanz. In 1999, he was appointed scientific member of the Max Planck Society, director at the Max Planck Institute of Quantum Optics and honorary professor at the Technical University of Munich. He declined simultaneous offers to ETH Zurich, Switzerland, and the University of Bayreuth, Germany.
== Achievements ==
Rempe is considered a pioneer of the field of cavity quantum electrodynamics. He was first to observe how a single atom repeatedly emits and absorbs a single photon.<ref name="Rempe Walther Klein pp. 353–356">{{cite journal | last1=Rempe | first1=Gerhard | last2=Walther | first2=Herbert | last3=Klein | first3=Norbert | title=Observation of quantum collapse and revival in a one-atom maser | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=58 | issue=4 | date=26 January 1987 | issn=0031-9007 | doi=10.1103/physrevlett.58.353 | pages=353–356| pmid=10034912 | bibcode=1987PhRvL..58..353R }}</ref> First experiments he performed with microwave photons in superconducting cavities. Later he expanded his interest to optical photons between mirrors of highest possible reflectivity.<ref name="Thompson Rempe Kimble pp. 1132–1135">{{cite journal | last1=Thompson | first1=R. J. | last2=Rempe | first2=G. | last3=Kimble | first3=H. J. | title=Observation of normal-mode splitting for an atom in an optical cavity | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=68 | issue=8 | date=24 February 1992 | issn=0031-9007 | doi=10.1103/physrevlett.68.1132 | pages=1132–1135| pmid=10046088 | bibcode=1992PhRvL..68.1132T | url=https://resolver.caltech.edu/CaltechAUTHORS:THOprl92 | url-access=subscription }}</ref> His experiments laid the foundation for the development of quantum nonlinear optics, in which a single particle, be it an atom or a photon, causes an effect that many particles cannot induce.<ref name="Rempe Thompson Brecha Lee pp. 1727–1730">{{cite journal | last1=Rempe | first1=G. | last2=Thompson | first2=R. J. | last3=Brecha | first3=R. J. | last4=Lee | first4=W. D. | last5=Kimble | first5=H. J. | title=Optical bistability and photon statistics in cavity quantum electrodynamics | journal=Physical Review Letters | publisher=American Physical Society (APS) | volume=67 | issue=13 | date=23 September 1991 | issn=0031-9007 | doi=10.1103/physrevlett.67.1727 | pages=1727–1730| pmid=10044232 | bibcode=1991PhRvL..67.1727R | url=https://resolver.caltech.edu/CaltechAUTHORS:REMprl91 | url-access=subscription }}</ref>
Rempe has used his findings from basic research to develop novel interfaces between light and matter.<ref name="Wilk Webster Kuhn Rempe pp. 488–490">{{cite journal | last1=Wilk | first1=Tatjana | last2=Webster | first2=Simon C. | last3=Kuhn | first3=Axel | last4=Rempe | first4=Gerhard | title=Single-Atom Single-Photon Quantum Interface | journal=Science | publisher=American Association for the Advancement of Science (AAAS) | volume=317 | issue=5837 | date=27 July 2007 | issn=0036-8075 | doi=10.1126/science.1143835 | pages=488–490| pmid=17588899 | bibcode=2007Sci...317..488W | s2cid=31968050 | doi-access=free }}</ref> These interfaces connect the everyday world with the quantum world and have potential applications as senders, receivers and memories of information in a future global quantum network.<ref name="Ritter Nölleke Hahn Reiserer 2012 pp. 195–200">{{cite journal | last1=Ritter | first1=Stephan | last2=Nölleke | first2=Christian | last3=Hahn | first3=Carolin | last4=Reiserer | first4=Andreas | last5=Neuzner | first5=Andreas | last6=Uphoff | first6=Manuel | last7=Mücke | first7=Martin | last8=Figueroa | first8=Eden | last9=Bochmann | first9=Joerg | last10=Rempe | first10=Gerhard | title=An elementary quantum network of single atoms in optical cavities | journal=Nature | volume=484 | issue=7393 | year=2012 | issn=0028-0836 | doi=10.1038/nature11023 | pages=195–200| pmid=22498625 | arxiv=1202.5955 | bibcode=2012Natur.484..195R | s2cid=205228562 }}</ref> A remarkable feature of the interface is its ability to detect single photons nondestructively,<ref name="Reiserer Ritter Rempe pp. 1349–1351">{{cite journal | last1=Reiserer | first1=A. | last2=Ritter | first2=S. | last3=Rempe | first3=G. | title=Nondestructive Detection of an Optical Photon | journal=Science | volume=342 | issue=6164 | date=14 November 2013 | issn=0036-8075 | doi=10.1126/science.1246164 | pages=1349–1351| pmid=24231809 | arxiv=1311.3625 | bibcode=2013Sci...342.1349R | s2cid=5280237 }}</ref> which opens new perspectives for a scalable quantum computer.<ref name="Reiserer Kalb Rempe Ritter pp. 237–240">{{cite journal | last1=Reiserer | first1=Andreas | last2=Kalb | first2=Norbert | last3=Rempe | first3=Gerhard | last4=Ritter | first4=Stephan | title=A quantum gate between a flying optical photon and a single trapped atom | journal=Nature | volume=508 | issue=7495 | date=9 April 2014 | issn=0028-0836 | doi=10.1038/nature13177 | pages=237–240| pmid=24717512 | arxiv=1404.2453 | bibcode=2014Natur.508..237R | s2cid=205238109 }}</ref> The interface is also suitable to observe and control the motion of a single atom in real time,<ref name="Pinkse Fischer Maunz Rempe 2000 pp. 365–368">{{cite journal | last1=Pinkse | first1=P. W. H. | last2=Fischer | first2=T. | last3=Maunz | first3=P. | last4=Rempe | first4=G. | title=Trapping an atom with single photons | journal=Nature | publisher=Springer Science and Business Media LLC | volume=404 | issue=6776 | year=2000 | issn=0028-0836 | doi=10.1038/35006006 | pages=365–368| pmid=10746717 | bibcode=2000Natur.404..365P | s2cid=4401987 }}</ref><ref name="Kubanek Koch Sames Ourjoumtsev 2009 pp. 898–901">{{cite journal | last1=Kubanek | first1=A. | last2=Koch | first2=M. | last3=Sames | first3=C. | last4=Ourjoumtsev | first4=A. | last5=Pinkse | first5=P. W. H. | last6=Murr | first6=K. | last7=Rempe | first7=G. | title=Photon-by-photon feedback control of a single-atom trajectory | journal=Nature | publisher=Springer Science and Business Media LLC | volume=462 | issue=7275 | year=2009 | issn=0028-0836 | doi=10.1038/nature08563 | pages=898–901| pmid=20016597 | bibcode=2009Natur.462..898K | s2cid=4432136 }}</ref> as well as to generate quantum light with noise below the shot noise level.<ref name="Ourjoumtsev Kubanek Koch Sames 2011 pp. 623–626">{{cite journal | last1=Ourjoumtsev | first1=A. | last2=Kubanek | first2=A. | last3=Koch | first3=M. | last4=Sames | first4=C. | last5=Pinkse | first5=P. W. H. | last6=Rempe | first6=G. | last7=Murr | first7=K. | title=Observation of squeezed light from one atom excited with two photons | journal=Nature | volume=474 | issue=7353 | year=2011 | issn=0028-0836 | doi=10.1038/nature10170 | pages=623–626| pmid=21720367 | arxiv=1105.2007 | bibcode=2011Natur.474..623O | s2cid=4301174 }}</ref>
Rempe has also done pioneering work in the field of atom optics and quantum gases. By means of an atom interferometer he was able to demonstrate experimentally that for an observed object passing through a double-slit arrangement quantum mechanical wave-particle duality is based on entanglement, instead of Heisenberg's uncertainty relation for position and momentum, as often stated in textbooks.<ref name="Dürr Nonn Rempe 1998 pp. 33–37">{{cite journal | last1=Dürr | first1=S. | last2=Nonn | first2=T. | last3=Rempe | first3=G. | title=Origin of quantum-mechanical complementarity probed by a 'which-way' experiment in an atom interferometer | journal=Nature | publisher=Springer Science and Business Media LLC | volume=395 | issue=6697 | year=1998 | issn=0028-0836 | doi=10.1038/25653 | pages=33–37| bibcode=1998Natur.395...33D | s2cid=39920777 }}</ref> He has produced the first Bose-Einstein condensate outside the U.S. and has used it to generate, among others, a strongly correlated gas of molecules by means of the quantum Zeno effect.<ref name="Syassen Bauer Lettner Volz pp. 1329–1331">{{cite journal | last1=Syassen | first1=N. | last2=Bauer | first2=D. M. | last3=Lettner | first3=M. | last4=Volz | first4=T. | last5=Dietze | first5=D. | last6=García-Ripoll | first6=J. J. | last7=Cirac | first7=J. I. | last8=Rempe | first8=G. | last9=Dürr | first9=S. | title=Strong Dissipation Inhibits Losses and Induces Correlations in Cold Molecular Gases | journal=Science | volume=320 | issue=5881 | date=6 June 2008 | issn=0036-8075 | doi=10.1126/science.1155309 | pages=1329–1331| pmid=18535241 | arxiv=0806.4310 | bibcode=2008Sci...320.1329S | s2cid=13004535 }}</ref>
In a third research focus Rempe follows the goal to produce an ultracold gas of polyatomic molecules. The focus lies on the development of novel methods for slowing down complex molecules using a centrifuge<ref name="Chervenkov Wu Bayerl Rohlfes p. ">{{cite journal | last1=Chervenkov | first1=S. | last2=Wu | first2=X. | last3=Bayerl | first3=J. | last4=Rohlfes | first4=A. | last5=Gantner | first5=T. | last6=Zeppenfeld | first6=M. | last7=Rempe | first7=G. | title=Continuous Centrifuge Decelerator for Polar Molecules | journal=Physical Review Letters | volume=112 | issue=1 | date=6 January 2014 | issn=0031-9007 | doi=10.1103/physrevlett.112.013001 | article-number=013001| pmid=24483892 | arxiv=1311.7119 | s2cid=31657286 }}</ref> and for cooling such molecules using the Sisyphus effect.<ref name="Zeppenfeld Englert Glöckner Prehn 2012 pp. 570–573">{{cite journal | last1=Zeppenfeld | first1=Martin | last2=Englert | first2=Barbara G. U. | last3=Glöckner | first3=Rosa | last4=Prehn | first4=Alexander | last5=Mielenz | first5=Manuel | last6=Sommer | first6=Christian | last7=van Buuren | first7=Laurens D. | last8=Motsch | first8=Michael | last9=Rempe | first9=Gerhard | title=Sisyphus cooling of electrically trapped polyatomic molecules | journal=Nature | volume=491 | issue=7425 | year=2012 | issn=0028-0836 | doi=10.1038/nature11595 | pages=570–573| pmid=23151480 | arxiv=1208.0046 | bibcode=2012Natur.491..570Z | s2cid=4367940 }}</ref> The aim is to understand chemical reactions at low temperatures, to open new reaction channels, to prepare molecules for precision experiments, as well as producing neutral quantum many-body systems with a long-range electrical interaction.
In addition to his research and teaching activities, Rempe was and is engaged in academic self-administration, such as speaker of the Quantum Optics and Photonics section of the German Physical Society, the curator of several magazines such as "Physics in our Time", "Journal of Optics" and "Optics Communications", as chairperson of a selection panel of the European Research Council, as managing director of the Max Planck Institute of Quantum Optics and chairperson of the prize committee of the Stern-Gerlach medal of the German Physical Society.
== References == <references/>
== External links == * [https://web.archive.org/web/20150216144006/http://www.mpq.mpg.de/4544950/employee_page?c=4938424&employee_id=34830 Homepage G. Rempe at MPQ] * [http://www.mpq.mpg.de/quantumdynamics Group Homepage at MPQ] * [http://www.mpq.mpg.de/cms/mpq/en/index.html Max Planck Institute of Quantum Optics] * [http://www.ccqed.eu/ Circuit and Cavity Quantum Electrodynamics (CCQED)]
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{{DEFAULTSORT:Rempe, Gerhard}} Category:21st-century German physicists Category:1956 births Category:Living people Category:20th-century German physicists Category:University of Duisburg-Essen alumni Category:LMU Munich alumni Category:Max Planck Institute directors Category:Academic staff of Vrije Universiteit Amsterdam Category:Academic staff of the University of Konstanz Category:Academic staff of the Technical University of Munich Category:German experimental physicists Category:People from Bottrop