• B.S. 1961, University of Ottawa
• M.A., 1962, University of Ottawa
• D. Phil, 1967, University of Oxford (England)

Research Interests:

Professor Symko’s field of research is in very low temperature physics, superconductivity, solid state, and thermoacoustics. His current areas of research are in quasicrystals and thermoacoustics, where he is investigating the basic phenomena and their applications. In the field of quasicrystals he and his group have developed methods of producing thin films of quasicrystals for studies of mechanical, transport, and optical properties; films of this new class of materials are important for coatings and a variety of applications. Of special interest is the formation of the quasicrystalline state in the form of thin films and its interaction with substrates. Investigations of the properties of the QC films consist of optical transmission and reflectivity, tunneling with STM, XPS, and AFM. The characteristics of the film surface, important for application due to the low surface energy, are determined by friction measurements, liquid drop-solid contact angle, and by AFM. As a consequence of the low surface energy, this material has an extremely low coefficient of friction and it has a non-stick surface; yet it is very strong. Since many of the unusual properties of quasicrystals can be related to a pseudogap in the electronic density of states, this gap has been investigated using tunneling and optical techniques. Many of the unusual properties of this class of materials can be attributed to its cluster structure.

Thermoacoustic devices are becoming important for applications dealing with current energy issues. Such devices are attractive because the working gases do not pollute the environment, they are simple and have good efficiencies. There are essentially two basic devices, one where heat produces sound and one where sound pumps heat. The latter is a refrigerator or a heat pump, with essentially no moving parts. Professor Symko and his group are developing such a refrigerator for small scale applications in heat management for microcircuits and computers where heat is pumped by a high frequency sound or an ultrasound. Because this type of cooler is simple it is being adapted to miniaturization and electronic circuit interfacing. The second type of thermoacoustic device, where heat produces sound, has also many applications. This device shows much promise as an energy converter where heat is directly converted to electricity. It is especially important for waste heat management. There are fundamental questions of efficiency and onset of oscillations triggered by fluctuations, instabilities, heat flow and heat transfer on microscopic scales, and dissipation in nanoscale structures. The onset of acoustic oscillations is an interesting example of a non-equilibrium phase transition to a coherent state in the presence of thermal fluctuations and non-linearities. Miniaturization of this type of device using MEMS technology leads to arrays with high power densities with numerous energy conversion applications.

Selected Recent Publications

• "Observation of a Narrow Pseudo-Gap Near the Fermi Level of AlCuFe Quasicrystalline Thin Films" (with T. Klein. D.N. Davydov and A.G.M. Jansen), Phys. Rev. Lett. 74, 3656 (1995).
• "Macroscopic Quantum Tunneling in Long Josephson Junctions," in Quantum Tunneling of the Magnetization, ed. By Barbara and Gunther (NATO ASI Series 1995), Vol. 301, p. 481.
• "Quasicrystal Thin Films for Biomedical Applications" (with W. Park and D. Kieda), in Proc. of the 11th Intern. Conf. On Surface Modification Technologies, ed. T.S. Sudarshan, M. Jeandin, and K. Khor (1998), p. 1051.
• "Energy Conversion Using Thermoacoustic Devices," Proc. of 18th International Conference on Thermoelectricity, 1999, p. 645, the International Thermoelectric Society.
• "Miniaturization of Thermoacoustic Devices for Thermal Management of Microelectronics," Heat Transfer and Transport Phenomena in Microscale, 2000, p. 335, Begell House, Inc., New York, Ed. C.P. Celata.
• "Design and Development of High Frequency Thermoacoustic Engines for Thermal Management in Microelectronics" (with E. Abdel-Rahman, Y.S. Kwon, M. Emmi, and R. Behunin), Microelectronics J. 35, 185 (2004).