Professor Doctor Werner Keune of the University of Duisburg-Essen has spent more than 38 years (nearly four decades!) of his academic life focusing on the various applications of Mössbauer spectroscopy.
Professor Keune (known simply as Werner in our community) officially retired in January 2006, but continues to be a very active Mossbauer researcher.
Over the last four decades Werner
has been the author/co-author of almost 200 research papers, with scientific collaborations from a very large number of countries, including Brazil, the US, Italy, India, Japan, Russia, Romania, and Spain.
He has made significant contributions to the applications of this technique in specialized areas, such as thin films, surfaces and interfaces, and multilayers, and is considered to be a world-class Mössbauer researcher and an esteemed physicist.
Werner Keune was born on 11 June 1939 in Saarbrücken, Germany.
Werner grew up in Southern Germany in a small town near the city of Heilbronn, where the great natural scientist and physician Julius Robert von Mayer proposed the first law of thermodynamics in 1842.
as a graduate student in front of his
rare-gas matrix isolation apparatus.
Picture taken in the Science Center, Thousand Oaks, California, USA, in 1968.
Bottom row: Ulrich Gonser (first from right), Werner Keune
(second from right).
In 1969, Werner returned to the Technical University of Munich and received his Ph.D. degree.
Also in 1969, almost simultaneously with Alfred "Ali" X. Trautwein, Werner Keune joined the newly established Mössbauer spectroscopy group of Professor Ulrich Gonser at the Institute of Metal Physics, University of Saarland, in Saarbrücken, Germany, and later became Assistant Professor and leader of the project "Mössbauer Spectroscopy Applied to Ferroelectrics" within the "Sonderforschungsbereich" (research network) on ferroelectrics.
is thankful to Uli Gonser for the inspiring atmosphere and scientific freedom found in his institute.
In that year, in the foreign student club of the Saarbrücken campus, Werner met for the first time his later wife, Ingeborg Krummel, a high school teacher in biology and geography.
At Saarbrücken, in collaboration with Istvan Dezsi (Budapest) and Sadgopal K. "Ashok" Date (the Alexander von Humboldt post-doc Fellow from India), Werner investigated photorefractive Fe centers, valency conversion, and spin relaxation effects in ferroelectric LiNbO3:57Fe.
Together with Saburo Nasu (Japan), Don L. Williamson (USA), and Teruya Shinjo (Japan), who all worked as post-docs at Saarbrücken, Werner
applied Mössbauer spectroscopy to study Fe-Ni Invar alloys, fcc-Fe precipitation in CuFe alloys, and interface magnetism in nanoscaled ultrahigh-vacuum (UHV) grown Fe/Cu multilayers using the 57Fe probe-layer technique for the first time .
In 1972, Werner Keune
worked in Brazil as "technical expert" of the IAEA (Vienna) in order to support the Mössbauer spectroscopy group of Alexandre Sette Camara in Belo Horizonte.
Werner Keune received the degree of "Habilitation" at Saarbrücken in 1975, and in the same year moved to the Department of Physics, University of Duisburg (now University of Duisburg-Essen) in Duisburg, Germany, after accepting an invitation to join as Professor of Applied Physics.
, together with Joachim Lauer and Hans-Dieter Pfannes, Professor Keune
had to build up a new Mössbauer spectroscopy laboratory from scratch.
Werner Keune and his group at Duisburg in 1999, with visiting scientists (top row) Hans-Dieter Pfannes, Brazil (first from right) and Masaaki Doi, Japan (fifth from right).
Professor Keune's activities in DCEMS resulted in close and fruitful worldwide cooperation with Professor Kazuo Hisatake (Japan) and his coworkers at that time (Tamotsu Toriyama and Keiji Saneyoshi), David Liljequist (Sweden), Rudi H. Nussbaum (USA), Joan Parellada (Spain), Ognian Nikolov (Bulgaria), and Helfried Reuther (Germany).
In cooperation with Fabienne Richomme and Professor Jacques Teillet (France) Werner Keune and his group investigated Tb/Fe multilayers by Mössbauer spectroscopy for many years.
Werner Keune was group leader in the state-funded research networks ("Sonderforschungsbereich") "Structural and Magnetic Phase Transitions in Transition Metal Alloys and Compounds" and "Magnetic Heterostructures" between groups of the Ruhr-Univerity Bochum and the University of Duisburg-Essen.
Further, from 1984-1986 he served as vice-chairman, and from 1986-1988 as chairman, of the Department of Physics.
has been always attracted to Japanese science and culture.
Professors Ko Mibu, Teruo Ono, Takeshi Emoto, Nobuyoshi Hosoito, and Saburo Nasu, all reputed Mössbauer scientists, stayed in Professor Keune's
laboratory for some time.
also enjoyed working in laboratories in other countries.
In 1991 he
spent a sabbatical at the California Institute of Technology
in Pasadena, USA, with Professor Brent Fultz as his
host, and worked on Mössbauer diffraction.
In 1996 he
had a sabbatical stay first at the Laboratoire de Magnetism, C.N.R.S., in Grenoble (France), hosted by Dominique Givord, and later at the Materials Science Division, Argonne National Laboratory
at Argonne (USA) in the group of Sam D. Bader, where he
studied epitaxial fcc-Fe ultrathin films on diamond C(001).
Werner Keune with graduate students (from left) Ellen Schuster, Balaram Sahoo, and Robert Peters in Chicago during a visit to the Advanced Photon Source at the Argonne National Laboratory, in November 2003.
At Argonne, the Advanced Photon Source had just begun to operate, and Ercan Alp, group leader at the nuclear resonance beamline, invited Werner to cooperate on nuclear resonance inelastic X-ray scattering (NRIXS) experiments on thin films and multilayers.
The first successful NRIXS experiments on thin films were performed at that time .
In cooperation with the beamline staff, Werner
group measured the vibrational density of states of 57Fe and 119Sn atoms in various crystalline and amorphous binary alloy films and multilayers.
Anomalous non-Debye-like low-energy vibrational excitations in amorphous alloy films , phonon confinement in multilayers , and metastable interfacial alpha-Sn in Sn/Si multilayers  have been investigated by NRIXS.
In the new millenium, Werner Keune
has focused his
research on NRIXS and on the determination of the Fe spin structure in magnetic heterostructures by Mössbauer spectroscopy.
The use of the 57Fe probe-layer technique, combined with conversion electron Mössbauer spectroscopy, allowed the study of the chemical state and spin structure at buried interfaces in exchange-biased ferromagnetic/antiferromagnetic bilayers, such as Fe/FeSn2
[16,17] and Fe/MnF2 .
has also demonstrated the usefulness of 57Fe probe-layer CEMS for the characterization of buried interfaces in spintronics materials, such as Fe/GaAs
[19,20], and Fe/GaAs-based HEMT heterostructures .
Recently, Werner Keune
and Ashok Date (India) began joint research activities on nanomagnetic materials.
In particular, metastability of cations at the crystallographically inequivalent lattice sites in nanoferrites (soft chemical approaches) is being pursued using a variety of physico-chemical techniques.
Werner also recently started collaborations with Professor Beatriz Roldan Cuenya (Department of Physics, University of Central Florida, USA) on the atomic vibrational dynamics of self-organized isolated nanoparticles and with Professors George Filoti and Victor E. Kuncser (Bucharest, Romania) on Mössbauer studies of magneto-electronics materials.
Werner Keune (seated) and Ashok Date in Werner's office at Duisburg in 2006
has published about 200 papers, about 185 of them dealing with Mössbauer spectroscopy.
He retired from the University of Duisburg-Essen in January 2006.
Werner plans to continue his
research interests in thin films, surfaces, interfaces, and nanoparticles, working with Mössbauer spectroscopy in cooperation with other groups.
accepted an appointment as Distinguished Visiting Professor at the University of Central Florida
(USA) for the Spring term in 2007.
hobbies are occasional tennis with his
son Philipp, golf, foreign languages, and, above all, playing with his
four-year old granddaughter Clara in his
daughter Christina's apartment in Cologne.
From the very beginning of his
research activities, Werner
and his Duisburg Mössbauer Group
have been a source of inspiration to eager coworkers from outside Germany.
In fact, his
students, post-docs, and academic and technical staff members have always made their visitors feel very comfortable and welcomed by their top-class facilities, warm hospitality, and attention, which may be the greatest gift and b