Report to the 1999 General Assembly for 1996-99
A large number of laboratories worldwide, in universities and public institutions as well as in private companies, are doing a leading research work in the broad field of quantum electronics, which, according to the C-17 mandate, encompasses the physics of coherent electromagnetic energy generation and transmission, the physics of interaction of coherent electromagnetic radiation with matter, and the application of quantum electronics to technology. The membership of C-17 tries to reflect this technical-scientific as well as geographic variety of interests: 8 members are from Europe, 1 from Russia, 4 from Pacific Rim, and 2 from North America. Of them, 8 are from Universities, 6 from Research Institutions, and 1 from Industry. (At this regard, with a deep sorrow and grief, we have to report the sudden and untimely death, occurred in December, 1998, of one of C-17 members, Professor Nikolai Koroteev. Prof. Koroteev, 51 years old, was director of the International Laser Center, and Head of the Chair of General Physics and Wave Processes at the M.V. Lomonosov Moscow State University. One of the leading scientists in nonlinear optics, he will be greatly missed by his colleagues.)
Most of the work of the Commission is now being done by e-mail, but at least an annual meeting is held, generally during a major conference sponsored by C-17 at which a majority of members would be expected to attend. The meeting site is usually rotated among the geographic areas, also in order to try to evenly distribute in the three-year period the cost of the travelling.
In the past three years the Commission meetings were held in Sydney (Australia, 1996), Hangzhou (China, 1997), and San Francisco (USA, 1998). The first meeting was convened at Sydney on July 16, 1996, during the International Quantum Electronics Conference (IQEC '96). The second meeting was held in Hangzhou on June 3, 1997 on the occasion of the 13th International Laser Spectroscopy Conference. The third meeting was held in San Francisco on May 7, 1998, during the International Quantum Electronics Conference (IQEC'98). This was the only case where the meeting took place on the occasion of a conference not sponsored by our Commission (just because the organizers had not applied for sponsorship; IQEC, in fact, remains one of the major international events in the area of quantum electronics and applications).
The 1999 meeting is likely to go back to Europe, and to be convened in Naples (Italy) in the period 24-29 May during which ICSSUR '99, the 6th International Conference on Squeezed States and Uncertainty Relations, will occur.
Six international events (5 conferences and 1 school) were recommended by the C-17 Commission; all the conferences awarded patronage of the IUPAP. The situation, therefore, was very similar to that in the previous three-year term, when six meetings were sponsored. The events sponsored in the 1997-1999 term were as follows:
1997 - 5th International Conference on Squeezed States and Uncertainty Relations (ICSSUR'97), Balatonfured, Hungary, May 27-31, 1997
- 13th International Laser Spectroscopy Conference (THICOLS), Hangzhou, China, June 2-6, 1997
1998 - 16th International Conference on Coherent and Nonlinear Optics (ICONO'98), Moscow, Russia, June 29 - July 3, 1998
- 2nd Workshop on Optoelectronic Materials and their Applications, Havana, Cuba, November 2-6, 1998 [co-sponsored with C-8 Commission]
1999 - 6th International Conference on Squeezed States and Uncertainty Relations (ICSSUR '99), Naples, Italy, May 24-29, 1999.
All these conferences have met the IUPAP guidelines concerning international participation and free circulation of scientists, as well as the other IUPAP policy matters. The Commission during this term of office has received no complaints.
Developments in the Field
The international meetings sponsored by the Commission have been very effective in gathering a high number of experts, and in providing them a suitable forum where to discuss the most recent advances and the perspectives of a continuously growing field.
Let us very briefly consider some of the hot topics:
R&D of novel or advanced laser sources
An important trend in quantum electronics has been the development of increasingly robust and practical sources of coherent radiation. This aim has been made possible by the recent advances in diode laser technology, solid state laser technology, and nonlinear frequency conversion.
Diode laser output powers have been increasing, as has the range of room temperature operating wavelengths, extending on one side towards the UV (e.g. GaN blue diode lasers) and on the other side into the mid-IR (both quantum cascade and more traditional semiconductor lasers have been developed). Injection diode lasers in the GaN system have been demonstrated, and products are expected to appear on the market in a short term. The high-power near-IR diodes have also enabled the development of other devices, like the fiber lasers (with outputs in excess of 10 W) and the multiwatt green and blue sources, constituted by diode-pumped frequency-doubled solid-state lasers, such as frequency-doubled Nd:YAG or Nd:YVO4.
Solid-state lasers continue to be object of R&D for generation of new wavelengths or as drivers of nonlinear optical converters, such as optical parametric oscillators. An increasing attention is being focused onto rare-earth-doped integrated optical devices (in glass, lithium niobate or silicon material systems), having in mind the development of advanced components especially for optical telecom systems.
Novel light emitting materials, such as nanoporous or amorphous silicon, photoluminescent polymers, and room temperature operating tunable lasers based on color centers in fluorides are also being explored.
Ultrashort-pulse lasers and nonlinear optics
The advances in laser technology, in turn, have fueled rapid progress in more basic research. A wide range of practical picosecond/femtosecond laser systems, enabled by nonlinear optical effects, have been demonstrated; record ultrafast pulses and their extension into the deep UV, which allow us to observe extremely high-order nonlinear effects, have represented important recent achievements.
Developments of nonlinear optics have included for example the generation of squeezed states photons, the exploitation of quantum coherence effects to obtain lasing without inversion and electromagnetically induced transparency, and the use of transverse effects to achieve optical switching by spatial solitons. Quantum mechanical aspects of laser beam propagation, and the role of local field effects in dense atomic media have also been the subject of investigations. Cooling and trapping of ions and neutral atoms also continue to hold special interest to this scientific community.
Much work is being devoted to the study of the nonlinear properties of nanostructured materials, including photonic band gap materials, or photonic crystals, nanocomposite materials, and quasi-phase matched materials for efficient second-order nonlinear effects.
It is clear that ultrafast and nonlinear optics have an important synergy that will benefit both fields in the future.
Laser and ultrafast-laser applications
Many industrial applications are taking advantage of the higher variety, higher power, higher compactness and ruggedness of recently developed laser sources. These "industrial-quality" lasers are opening up new manufacturing, metrologic and medical applications.
Near-IR laser diodes and amplifiers are of great importance in optical communications systems, where ultrafast optical technologies may be used to provide new kinds of capabilities.
The availability of LEDs, ELEDs and LDs in an increasingly wide wavelength range enables the development of effective and rugged optical sensors, while high-power solid state lasers are the core of remote sensing systems (e.g. LIDARs).
The use of ultrafast tools in biological imaging, material removal for precision machining and medical applications represents another area of active R&D.
Established areas of ultrafast science, such as spectroscopy, continue to provide important insights into the physics and chemistry of fundamental processes. In particular, ultrafast spectroscopy has provided a wealth of new information about the dynamics and function of many biological systems.
The recent demonstrations of quantum teleportation, still using ultrafast technology, definitely are among the most exciting new applications in basic science.
Other exciting new topics in technology are concerned with the generation of extreme ultra-violet (XUV) and/or x-ray radiation. Techniques include high harmonic generation and laser-plasma formation using ultra-intense femtosecond and nanosecond laser pulses, and x-ray generation using femtosecond electron bunches. Nano-machining of a large variety of materials would represent a follow-up application of these new sources.
Such a vigorous situation ensures the reason for the existence of the Quantum Electronics Commission in IUPAP, and stimulates close cooperation with other Commissions, first of all with AC-1 (ICO) and C15.
Giancarlo C. Righini, Chairman email@example.com