Eva Papilaya dan Yohanis Ngili
PENGHARGAAN bergengsi dan prestisius yang selalu diimpikan oleh semua peneliti di planet ini adalah hadiah Nobel. Begitu pun dengan para ahli yang bergelut dalam mengungkap rahasia alam dalam bidang fisika. Untuk tahun 2005 ini, penghargaan Nobel Fisika dianugerahkan kepada tiga orang fisikawan terkemuka yang bergelut dalam bidang fisika optik. Mereka adalah Roy J. Glauber (80) dari Universitas Harvard, AS, John L. Hall (71) dari National Institute of Standards and Technology, AS, dan Theodor W. Hänsch (64) dari Max-Planck-Institut fuer Quantenoptik, Universitas Munich, Jerman.
Roy J. Glauber adalah seorang fisikawan yang berjasa meletakkan fondasi teori optika kuantum. Dengan teori Elektrodinamika Quantum (Quantum Electrodinamics/QED), Glauber menjelaskan secara jernih pertanyaan bagaimana memformulasikan teori kuantum untuk menjelaskan proses pendeteksian cahaya. Untuk mengenang jasanya yang besar tersebut, teori ini kemudian dikenal sebagai Teori Glauber. Dalam teori tersebut ia berhasil membedakan dengan baik sifat-sifat cahaya yang berasal dari sumber termal dan cahaya koheren yang berasal dari laser atau amplifier kuantum. Sementara itu, pekerjaan Glauber dilanjutkan dengan pengembangan spektroskopi dengan presisi tinggi menggunakan laser (laser-based precision spectroscopy) dan teknik penyisiran frekuensi optik yang dilakukan oleh John L. Hall dan Theodor W. Hänsch.
Glauber dilahirkan pada tahun 1925 di New York, AS dan memperoleh Ph.D. dalam bidang fisika di Harvard University. Kini ia menjadi profesor di almamaternya. Beberapa publikasinya yang berhubungan dengan bidang fisika optik antara lain diterbitkan di jurnal-jurnal fisika bergengsi seperti Physics Review A dengan judul Quantum Optics of Dielectric Media (1991) dan "Quantum Field Theory of Atoms Interacting With Photons III" (1996). Selain itu juga pada jurnal Quantum and Semiclassical Optics, dengan judul Wigner functions in the Paul trap yang diterbitkan tahun 1995. Tentunya ada puluhan hingga ratusan publikasi lain dalam bidang fisika optik.
Sedangkan, Dr. John L. Hall, lahir tahun 1934, adalah seorang profesor fisika di Universitas Colorado dan juga ilmuwan senior di National Institute of Standard and Technology (NIST) di Boulder, Colorado, AS. Sementara itu, Dr. Hänsch, lahir tahun 1941 di Heidelberg adalah seorang fisikawan berkebangsaan Jerman yang juga menjabat sebagai direktur Max Planck Institute for Quantum Optics (Max-Planck-Institut für Quantenoptik) yang terletak di Munchen, Jerman.
Hänsch tercatat sebagai orang Jerman ke-24 yang memperoleh hadiah Nobel. Atas karya monumental tersebut, ketiganya berhak atas hadiah senilai 1,3 juta dolar AS di mana Roy Glauber sebagai inisiator peletak dasar teori optika kuantum yang memaparkan sifat-sifat partikel cahaya berhak menerima setengah dari hadiah tersebut. Sedangkan setengahnya lagi dibagi rata oleh Hall dan Hänsch. Ketiga fisikawan optik ini menerima hadiah tersebut pada tanggal 10 Desember 2005. Penyerahan hadiah selalu dilaksanakan pada tanggal tersebut setiap tahunnya untuk mengenang Alfred Nobel yang meninggal pada tanggal 10 Desember 1896.
Fisik kuantum modern
Riset yang dilakukan oleh Roy Glauber dimulai sejak tahun 1960-an. Saat itu, ia sukses mengembangkan teori yang dapat menjelaskan sifat-sifat luar biasa sinar laser, khususnya dalam bidang fisika kuantum modern. Dengan sifat-sifat ini, ia dapat menjelaskan perbedaan mendasar antara sumber cahaya yang panas, misalnya dari bohlam dengan campuran frekuensi dan fase dengan laser yang memiliki frekuensi dan fase tertentu. Peristiwa ini dikenang sebagai awal dari pengembangan bidang fisika optika kuantum.
Cerita berawal pada tahun 1963, ketika Roy Glauber menuliskan dasar-dasar teorinya pada sebuah paper singkat yang ia kirim dalam jurnal Physical Review Letters dan kemudian dipublikasikan. Dalam teorinya, Glauber menyatakan bahwa penjelasan eksperimen korelasi foton harus berlandaskan pada aplikasi konsisten dari elektrodinamika kuantum. Pada paper tersebut Glauber memperkenalkan konsep kuasi-distribusi yang merupakan penggambaran kuantum dari satu keadaan, akan tetapi memiliki hubungan langsung dengan distribusi ruang fase klasik.
Sedangkan John Hall dan Theodor Hänsch yang berbagi setengah hadiah sisanya berperan mengembangkan spektroskopi menggunakan laser yang dapat digunakan untuk menentukan warna cahaya atom dan molekul dengan ketelitian yang tinggi. Di sini mereka mengembangkan teknik pembuatan sisir frekuensi optik menggunakan laser yang dapat digunakan untuk mengukur warna cahaya yang berbeda dengan sangat teliti. Dengan adanya temuan Hall dan Hänsch ini, pengukuran frekuensi dapat dilakukan lebih akurat hingga lima belas digit.
Fisika optika kuantum dan spektroskopi berbasis laser berpresisi tinggi ini sangat penting. Salah satu aplikasinya yaitu dalam definisi satuan-satuan yang digunakan dalam fisika, contohnya definisi satu meter. Satu meter diartikan sebagai jarak yang ditempuh cahaya dalam waktu 1/299.792.458 detik. Bukan itu saja aplikasinya, teori relativitas khusus Einstein pun telah berhasil dikonfirmasi sampai ketelitian yang sangat tinggi.
Teknik ini pula dijadikan dasar untuk mempelajari kestabilan konstanta alami waktu dan memperbaiki kemampuan teknologi global positioning system (GPS). Para peneliti juga mengaplikasikannya untuk mengembangkan jam atom yang lebih akurat. Dengan teknik tersebut, secara teori mereka hanya akan kehilangan satu detik sejak alam semesta terbentuk. Penggunaan lainnya adalah dalam upaya peningkatan keamanan dalam teknologi komunikasi dan dalam pemrosesan informasi.
http://www.opto.lipi.go.id/utama.cgi?cetakartikel&1135035672
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Roy J. Glauber
Roy Jay Glauber (born September 1, 1925) is an American theoretical physicist. He is the Mallinckrodt Professor of Physics at Harvard University and Adjunct Professor of Optical Sciences at the University of Arizona. Born in New York City, he was awarded one half of the 2005 Nobel Prize in Physics "for his contribution to the quantum theory of optical coherence", with the other half shared by John L. Hall and Theodor W. Hänsch.
In this work, published in 1963, he created a model for photodetection and explained the fundamental characteristics of different types of light, such as laser light (see coherent state) and light from light bulbs (see blackbody). His theories are widely used in the field of quantum optics.
Biography
Glauber was born in 1925 in New York City, a member of the 1941 graduating class of the Bronx High School of Science, and went on to do his undergraduate work at Harvard University. After his sophomore year he was recruited to work on the Manhattan Project, where (at the age of 18) he was one of the youngest scientists at Los Alamos. His work involved calculating the critical mass for the atom bomb. After two years at Los Alamos, he returned to Harvard, receiving his bachelor's degree in 1946 and his PhD in 1949.
Glauber has received many honors for his research, including the Albert A. Michelson Medal from the Franklin Institute in Philadelphia (1985),[1] the Max Born Award from the Optical Society of America (1985), the Dannie Heineman Prize for Mathematical Physics from the American Physical Society (1996), and the 2005 Nobel Prize in Physics. On 22 April 2008, Professor Glauber was awarded the 'Medalla de Oro del CSIC' ('CSIC's Gold Medal') in a ceremony held in Madrid, Spain.[2]
He currently lives in Arlington, Massachusetts and is the Mallinckrodt Professor of Physics at Harvard University, where both past and present students enthusiastically praised his teaching to Harvard Crimson reporters. On April 15, 2010 police in Arlington caught a man they suspected of breaking into Glauber's home, he was later convicted of breaking and entering, but in the end it was only a replica of Glauber's Nobel Prize that was stolen.
Glauber has two children, a son and a daughter, and five grandchildren.
Recent work
Glauber's recent research has dealt with problems in a number of areas of quantum optics, a field which, broadly speaking, studies the quantum electrodynamical interactions of light and matter. He is also continuing work on several topics in high-energy collision theory, including the analysis of hadron collisions, and the statistical correlation of particles produced in high-energy reactions.
Specific topics of his current research include: the quantum mechanical behavior of trapped wave packets; interactions of light with trapped ions; atom counting-the statistical properties of free atom beams and their measurement; algebraic methods for dealing with fermion statistics; coherence and correlations of bosonic atoms near the Bose–Einstein condensation; the theory of continuously monitored photon counting-and its reaction on quantum sources; the fundamental nature of “quantum jumps”; resonant transport of particles produced multiply in high-energy collisions; the multiple diffraction model of proton-proton and proton-antiproton scattering
Works by Glauber
- R. J. Glauber, Quantum Theory of Optical Coherence. Selected Papers and Lectures, Wiley-VCH, Weinheim 2007. (A collection of reprints of Glauber's most important papers from 1963 to 1999, selected by the author.)
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John L. Hall
Biography
Born in Denver, Colorado, Hall holds three degrees from Carnegie Institute of Technology, a B.S. in 1956, an M.S. in 1958, and a Ph.D. in 1961. He completed his postdoctoral studies at the Department of Commerce's National Bureau of Standards, now the National Institute of Standards and Technology (NIST), where he remained from 1962 until his retirement in 2004. He has lectured at the University of Colorado at Boulder since 1967.
Hall is currently a NIST Senior Fellow, Emeritus and remains a Fellow at JILA, formerly the Joint Institute for Laboratory Astrophysics, and Lecturer at the CU Boulder Physics Department. JILA is a research institute managed jointly by CU Boulder and NIST.
Hall's Nobel prize was awarded for his work on laser-based precision spectroscopy, and the optical frequency comb technique. The other half of the prize was awarded to Roy J. Glauber.
Hall has received many other honors for his pioneering work, including the Optical Society of America's Max Born Award "for pioneering the field of stable lasers, including their applications in fundamental physics and, most recently, in the stabilization of femtosecond lasers to provide dramatic advances in optical frequency metrology."
Honours and Award
- National Carbon Company Fellow in Physics, 1957–1961
- Department of Commerce Gold Medal, 1969
- Samuel W. Stratton Award, 1971
- Department of Commerce Gold Medal, 1974 (group awards)
- IR-100: Laser stabilizer selected as one of “100 best new products of the year,” 1975
- IR-100: Laser wavelength meter (“Lambdameter”) selected as one of “100 best new products of the year,” 1977
- E. U. Condon Award, 1979
- Charles Hard Townes Award of the Optical Society of America, 1984, jointly with V. P. Chebotayev (Academy of Sciences, USSR)
- Davisson-Germer Prize of the American Physical Society, 1988
- Docteur Honoris Causa de l’Universite Paris Nord, 1989
- Frederic Ives Medal of the Optical Society of America, 1991
- Arthur L. Shawlow Prize of the American Physical Society, 1993
- Allen V. Astin Measurement Science Award, 2000
- Max Born Award of the Optical Society of America, 2002[1]
- Presidential Rank Award from the Office of Personnel Management, 2002
- Department of Commerce Gold Medal, 2002 (group awards)
- Rabi Award of the IEEE Ultrasonics, Ferroelectrics, and Frequency Control Society, 2004[2]
- Légion d’Honneur Membership, 2004
- Nobel Prize in Physics, 2005
- Doctor of Science, honoris causa, University of Glasgow, 2007
http://en.wikipedia.org/wiki/John_L._Hall
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Theodor W. Hänsch
Theodor Wolfgang Hänsch (b. 30 October 1941 in Heidelberg, Germany) is a German physicist. He received one fourth of the 2005 Nobel Prize in Physics for "contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique", sharing the prize with John L. Hall and Roy J. Glauber.
Hänsch is Director of the Max-Planck-Institut für Quantenoptik (quantum optics) and Professor of experimental physics and laser spectroscopy at the Ludwig-Maximilians University in Munich, Bavaria, Germany.
Hänsch gained his Diplom and doctoral degree from Ruprecht-Karls-Universität Heidelberg in 1960s. Subsequently, he became a professor at Stanford University, California from 1975 to 1986. He was awarded the Comstock Prize in Physics from the National Academy of Sciences in 1983.[1] In 1986, he received the Albert A. Michelson Medal from the Franklin Institute.[2] In the same year Hänsch returned to Germany to head the Max-Planck-Institut für Quantenoptik. In 1989, he received the Gottfried Wilhelm Leibniz Prize of the Deutsche Forschungsgemeinschaft, which is the highest honour awarded in German research. In 2005, he also received the Otto Hahn Award of the City of Frankfurt am Main, the Society of German Chemists and the German Physical Society. In that same year, the Optical Society of America awarded him the Frederic Ives Medal and the status of honorary member in 2008.
One of his students, Carl E. Wieman, received the Nobel Prize in Physics in 2001.
In 1970 he invented a new type of laser which generated light pulses with an extremely high spectral resolution (i.e. all the photons emitted from the laser had nearly the same energy, to a precision of 1 part in a million). Using this device he succeeded to measure the transition frequency of the Balmer line of atomic hydrogen with a much higher precision than before. During the late 1990s, he and his coworkers developed a new method to measure the frequency of laser light to an even higher precision, using a device called the optical frequency comb generator. This invention was then used to measure the Lyman line of atomic hydrogen to an extraordinary precision of 1 part in a hundred trillion. At such a high precision, it became possible to search for possible changes in the fundamental physical constants of the universe over time. For these achievements he became co-recipient of the Nobel Prize in Physics for 2005.
Background to Nobel Prize
The Nobel Prize was awarded to Professor Hänsch in recognition for work that he did at the end of the 1990s at the Max Planck Institute in Garching, near Munich, Germany. He developed an optical "frequency comb synthesiser", which makes it possible, for the first time, to measure with extreme precision the number of light oscillations per second. These optical frequency measurements can be millions of times more precise than previous spectroscopic determinations of the wavelength of light.
The work in Garching was motivated by experiments on the very precise laser spectroscopy of the hydrogen atom. This atom has a particularly simple structure. By precisely determining its spectral line, scientists were able to draw conclusions about how valid our fundamental physical constants are - if, for example, they change slowly with time. By the end of the 1980s, the laser spectroscopy of hydrogen had reached the maximum precision allowed by interferometric measurements of optical wavelengths.
The researchers at the Max Planck Institute of Quantum Optics thus speculated about new methods, and developed the optical frequency comb synthesizer. Its name comes from the fact that it generates a light spectrum out of what are originally single-colour, ultrashort pulses of light. This spectrum is made of hundreds of thousands of sharp spectral lines with a constant frequency interval.
Such a frequency comb is similar to a ruler. When the frequency of a particular radiation is determined, it can be compared to the extremely acute comb spectral lines, until one is found that "fits". In 1998, Professor Hänsch received a Philip Morris Research Prize for the development of this "measurement device".
One of the first applications of this new kind of light source was to determine the frequency of the very narrow ultraviolet hydrogen 1S-2S two-photon transition. Since then, the frequency has been determined with a precision of 15 decimal places.
The frequency comb now serves as the basis for optical frequency measurements in large numbers of laboratories worldwide. Since 2002, the company Menlo Systems, in whose foundation the Max Planck Institute in Garching played a role, has been delivering commercial frequency comb synthesizers to laboratories all over the world.
http://en.wikipedia.org/wiki/Theodor_W._Hansch
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