Vladilen Stepanovich Letokhov (10 November 1939— 21 March 2009) Vladilen Letokhov was born in Taishet, Irkutsk region of Russia. In 1963 he graduated from Moscow Physical Technical Institute and started his PhD studies at Lebedev Physical Institute, where he worked till 1970. His PhD advisor was Nobel Laureate, acad. Niokolay Basov. In 1970, by invitation of Prof. Sergey Mandelshtam, he joined the Institute of Spectroscopy of the Russian Academy of Sciences (ISAN) where he headed the Laser Spectroscopy Department and used to be for a long time a vice-director for research. Since 1972 till 2008, Prof. Letokhov headed the chair of Quantum Optics at the Moscow Physical Technical Institute, which was founded by Acad. G. S. Lansberg. Among his students there are 60 PhDs and 12 Doctors of Sciences.
Prof. Vladilen Letokhov made seminal contributions to the various fields of laser physics and its applications, including laser spectroscopy, laser control of atomic motion, photoselective multiphoton chemistry, laser applications in nuclear physics and biomedicine, nanooptics, and in astrophysical spectroscopy. His key scientific achievements are summarized below.
In the field of laser spectroscopy, V.S. Letokhov made pioneering works on saturation spectroscopy. He proposed and realized resonance ionization spectroscopy (RIS), including laser detection of single atoms with many applications in analytics, study of highly excited states of rare atoms, first detection of molecules by RIS and resonant-enhanced multiphoton ionization (REMPI) with mass-spectrometry. Also, he developed the fluorescent photon-burst spectroscopy (detection of single atoms and very rare isotopes), photoacoustical and photothermal spectroscopy in combination with gas-chromatography and optoacoustical tomography of spatially inhomogeneous media. Methods of ultrafast spectroscopy were used also for study of ultrafast relaxation processes in high-temperature superconductors and fullerenes.
V.S. Letokhov received also seminal results in the field of laser spectroscopy with subwavelength spatial resolution. He proposed, persuaded during 20 years and finally experimentally realized laser resonant photoelectron microscopy with spatial resolution of about 30 nm and laser resonant photoion microscopy with resolution of about 5 nm. Moreover, he proposed a new type of scanning optical microscopy with nanometer spatial resolution based on resonance excitation of fluorescence from one-atom excited center.
In the field of laser control of atomic motion, V.S.Letokhov with coworkers made pioneering works in 1968 and 1973 on the trapping (channeling) of atoms by the gradient dipole force, proposed “optical lattices”, and introduced definition of Doppler limit for the laser cooling of atoms. He and his group made first experiments in 1979 on the cooling and monochromatization, collimation, and reflection of atomic beam with laser radiation. For the first time it was suggested to use the laser-like cavity for atomic-matter waves with high degeneracy and sharp focusing (to Angstrom size) of atomic beam. No doubt, V.S.Letokhov and his group made decisive contribution to the formation of a new field of research in atomic laser physics, atom optics in particular.
In the field of selective laser-matter interaction, V.S. Letokhov studied the resonance interaction between laser light and atoms and molecules. He with colleagues suggested, discovered, and developed a new field of research of principal importance—Photoselective Multiphoton Chemistry. Specifically, V.S.Letokhov made pioneering works that led to the creation of resonance stepwise ionization spectroscopy and a new laser isotope separation technique. He proposed and successfully demonstrated multiphoton resonance ionization of molecules (REMPI) in mass-spectrometry. Today this technique plays an exceptionally important role in probing molecular dynamics with molecular beams, etc.. V.S. Letokhov for the first time combined together the idea of photoselective excitation of vibrational states of molecules with subsequent excitation of reactive electronic states. Nowadays, photoselective multiphoton chemistry is one of the most powerful tools in photochemistry. V.S. Letokhov co-authored pioneering works in which phenomenon of multiple-photon photoselective (isotopically-selective) vibrational photoexcitation and photodissociation of polyatomic molecules by powerful IR laser pulse has been discovered. These and subsequent works led to the new field of research—the multiple-photon IR laser photophysics and photochemistry of molecules in the ground electronic state—and to the development of a new method for isotope separation by IR laser light, which was implemented by industry. The results in this field are summarized in the books.
V.S. Letokhov was also engaged into research on random lasers, nanooptics, nanophotonics, and nanoplasmonics. During last decade of his career he was studied laser effects in stellar atmospheres, which he predicted at the beginning of his career.
Letokhov’s works not only remain relevant at present, but also determine the development of many scientific areas. Letokhov’s research served as the basis for the work of Chu, Cohen-Tannuji and Phillips on laser methods of cooling atoms, for which they received the 1997 Nobel Prize in physics; some experts believe that the name of Letokhov could be among them.
- Lenin State Award for Science and Technologies (jointly with V.P. Chebotayev) for the works on nonlinear narrow resonances in optics and their applications (USSR, 1978)
- Honorary Jubilee International Medal of the 600 Years Anniversary of Heidelberg University (Germany, 1986)
- European Physical Society (EPS) Quantum Electronics Prize for pioneering and far-reaching contributions to the study of laser/matter interactions including atom optics, laser cooling, laser induced chemistry and laser analytical techniques (1998)
- State Award in Science and Technologies (jointly with the group of people) for the works on physical-technical foundations of laser isotope separation using selective multiphoton dissociation of molecules (2002)
- Rojdestvenskii Prize of the Russian Academy of Sciences (jointly with V.I. Balykin) for the works on laser cooling and trapping of atoms (Russia, 2001).
- Erlander award (Sweden, 2000)
- Honorary citizen of Troitsk (Russia, 2000)
- Doctor Honoris Causa/Honorary Professor of Ecole Normale Superiore de Paris (France), University of Arizona, Berkeley University, University of Iowa (USA), Lund University (Sweden)
- Fellow of the Optical Society of America (OSA, USA 1977)
- External member of the Max-Planck Society (Германия, 1989)
- Member of the European Academy of Arts and Sciences (1996)
- Fellow of the World Innovation Foundation (2000)
- Member of the European Academia (2002)
- Member of the Leibnitz Society (Germany, 2003).
Co-editor and editorial boards member of scientific journals
- Co-editor of the book series: Laser Science and Technology (Harwood Academic Publ) ed. by V.S.Letokhov, C.V.Shank, Y.R.Shen, and H.Walther (published 20 volumes).
- Co-editor of Lasers in the Life Sciences (1986-2009)
- Co-editor of Laser Chemistry (1982-2009)
- Co-editor of Nonlinear Optics (1991-2009)
- Journal of Experimental and Theoretical Physics (JETP) (1980-1982)
- Quantum Electronics (1974-2009)
- Optics Communications (1976-2009)
- Optics Letters (1977, 1979-1980, 1982-1986, 1988-1990)
- Comments on Atomic and Molecular Physics (1977-2009)
- Journal of Modern Optics (part “Optics Acta”) (1986-2009)
- Chemical Physics (1981-2009)
- Chemical Physics Letters (1991-2009)
- Nuovo Cimento B (1977-1982)
- Nuovo Cimento D и Р (1995-2009)
- Chinese Journal of Lasers (1989-1997)
- Applied Physics B (1980-1992)
- Laser Focus (1971-1982)
- Spectrochimica Acta B
- Journal of Applied Spectroscopy
- Heralds of the Russian Academy of Sciences
- Rojdestvenskii Optical Society (Russia) launched in 2011 the Letokhov Medal, which is awarded every two years to young scientists for the pioneering works in Laser Physics, Nonlinear Optics, and their applications.
- European Physical Society (EPS) launched in 2018 its highest award — EPS Vladilen Letokhov Award to recognize outstanding contributions in the field of laser-matter interaction, in particular spectroscopy of atoms and molecules, laser manipulation of atoms, and strong field processes. The medal is presented every odd year at a major European conference. The prize will consist of a medal, a certificate and a monetary award whose amount is presently set at 5000 euros.
- Pioneering works by Prof. Letokhov have been highlighted in 2018 during the ceremony of unveiling the European Physical Society (EPS) Historic Site to the Institute of Spectroscopy of the Russian Academy of Sciences, which plaque reads “This is the place where in a creative environment a team of talented young researchers inspired by Vladilen Letokhov made pioneering experiments on laser trapping and cooling of atoms, which paved the way to a whole bunch of new directions in physics, as well as on laser isotope separation using selected laser excitation of atoms and molecules, which finally led to the development of a new field of laser chemistry.”
- The memorial plaque «V.S. Letokhov ISAN 1970-2009» was installed in ISAN and the office of Letokhov was preserved as a memorial office.