The study of physics as a modern science was born in Europe, which has produced many great names in the field. This long tradition of excellence was extended yet again when the Royal Swedish Academy of Sciences announced the Nobel Prize for physics will go to the German scientist Theodor Hänsch for his pioneering work in spectroscopy. His research group at the Max Planck Institute of Quantum Optics is also involved in the EU-funded research project CONQUEST studying quantum phenomena.
Europe's scientific inquiry into the nature of physical laws got its start 400 years ago with the mathematical treaties of Galileo and Newton. The forward motion of that curiosity continues unabated to this day: many of the world's best physics research centres got their start – and continue to be staffed – thanks to European talent.
|Staff at the Max Planck Institute of Quantum Optics celebrating Theodor Hänsch's (front-left) success in this year's Nobel Prize for physics.|
One of the more renowned centres of physics research is the Max Planck Institute of Quantum Optics (MPQ) in Munich, which has its finger in a number of sub-atomic pies. Focused on basic experimental and theoretical research in the field of light-matter interaction, it develops – among other things – precision spectroscopy, or new laser techniques and their applications to atomic and plasma physics.
The Garching, Germany-based institute was itself the target, however, of a different kind of laser beam – the limelight of fame – with the recent revelation that one of its researchers was among the recipients of the coveted Nobel Prize for physics.
The Royal Swedish Academy of Sciences announced, earlier in October, that it awarded the 2005 honour in physics to Theodor Hänsch. He and US researcher John Hall will split half of the award for their contribution to the development of laser-based precision spectroscopy. The other half of the physics prize will go to US scientist Roy Glauber of Harvard University, USA for his work in the quantum theory of optical coherence.
According to the Academy, the work of Hänsch and Hall has made it possible to measure frequencies with an accuracy of fifteen ‘significant' digits. Lasers with extremely sharp colours can now be constructed and precise readings can be made of all colours. “This technique makes it possible to carry out studies of, for example, the stability of the constants of nature over time and to develop extremely accurate clocks and improved GPS technology,” the Academy said when announcing the winners.
Conquest of another kind
The process of selecting a winner of the Nobel Prize in physics starts in September, about a year before the prize is announced. Nominations reach the Swedish Academy of Sciences between September and February, with about 250-350 persons being nominated annually. Nominees are reviewed by the academy throughout the following summer, leading to final selections and the announcement of winners in October of each year. In December, Hänsch and the other Nobel science winners will travel to Stockholm to take part in the Academy's ceremonies where they will receive their medal, personal diploma, and a monetary award.
In addition to his work at the Max Planck Institute, Hänsch is also a member of the EU project CONQUEST (Controlled Quantum Coherence and Entanglement in Sets of Trapped Particles). The four-year Sixth Framework Programme (FP6) research, led by the Slovak Academy of Sciences, is building on pioneering science aimed at controlling the dynamics of individual quantum systems using small sets of trapped particles.
Professor Hänsch's contributions to laser spectroscopy – in particular, his application of the so-called ‘frequency comb' technique – caught the Academy's eye. The comb cleverly uses pulsed lasers for measuring optical frequency (light oscillations per second) with much greater precision than ever before. This is groundbreaking work, according to Dr Jakob Reichel, a CONQUEST team member and a former postdoc under Prof. Hänsch.
“For the first time, the frequency – that is, the colour – of light emitted by atoms and ions can now be directly measured in terms of the fundamental SI (internationally recognised) unit of frequency, which is realised in atomic clocks,” he notes.
Applications for this work range from the measurement of fundamental constants all the way to higher-bandwidth optical fibre communications. “In particular, the frequency comb opens the door for use of trapped atoms and ions (as studied in CONQUEST) as ‘clockwork' in optical clocks, which are expected to be more than 100 times more precise than the best clocks existing today,” explains Dr Reichel.
Professor Hänsch was born in 1941 and earned his PhD in 1969 from the University of Heidelberg. Between 1972 and 1986, he was a professor at Stanford University in California, USA. He was appointed director of MPQ in Garching and professor of experimental physics and laser spectroscopy at Ludwig-Maximilians-Universität in Munich.