A high-Q reflection notch method for measuring large dielectric losses in absorbing materials when using a stack resonator, which is a one-dimensional analogue of a capillary-in-a-waveguide technique, has been proposed. A detailed explanation of the effects that lay the basis of the method has been presented. The method is particularly accurate and sensitive for highly absorbing materials when other techniques are inadequate. The method can be used for dielectric spectroscopy of a broad range of liquid and solid materials, with applications in chemical, pharmaceutical and food industry, biomedical sciences, agriculture etc, in those frequency bands of infrared, millimeter wave and, especially, THz waves where dielectric losses are significant.
2. Baker-Jarvis, J., M. D. Janezic, B. F. Riddle, R. T. Johnk, P. Kabos, C. L. Holloway, R. G. Geyer, and C. A. Grosvenor, Measuring the Permittivity and Permiability of Lossy Materials: Solids, Liquids, Metals, Building Materials, and Negative-Index Materials, NIST, Boulder, CO, 2005.
3. Afsar, M. N., N. Suwanvisan, and Y. Wang, "Permittivity measurement of low and high loss liquids in the frequency range of 8 to 40 GHz using waveguide transmission line technique," Microw. Opt. Tech. Lett., Vol. 48, No. 2, 275-281, Feb. 2006.
4. Krupka, J., "Frequency domain complex permittivity measurements at microwave frequencies," Meas. Sci. Technol., Vol. 17, No. 6, R55-R70, Jun. 2006.
5. Sheen, J., "Comparisons of microwave dielectric property measurements by transmission/reflection techniques and resonance techniques," Meas. Sci. Technol., Vol. 20, No. 4, 042001, 2009.
6. Egorov, V. N., "Resonance methods for microwave studies of dielectrics (review)," Instrum. Exp. Tech., Vol. 50, No. 2, 143-175, Mar. 2007.
7. Akay, M. F., Y. V. Prokopenko, and S. Kharkovsky, "Resonance characteristics of whispering gallery modes in parallel-plates-type cylindrical dielectric resonators," Microw. Opt. Tech. Lett., Vol. 40, No. 2, 96-101, Jan. 2004.
8. Krupnov, A. F., V. N. Markov, G. Y. Golubyatnikov, I. I. Leonov, Y. N. Konoplev, and V. V. Parshin, "Ultra-low absorption measurement in dielectrics in millimeter- and submillimeter-wave range," IEEE Trans. Microw. Theory Tech., Vol. 47, No. 3, 284-289, Mar. 1999.
9. Addamo, G., G. Virone, D. Vaccaneo, R. Tascone, O. A. Peverini, and R. Orta, "An adaptive cavity setup for accurate measurements of complex dielectric permittivity," Progress In Electromagnetics Research, Vol. 105, 141-155, 2010.
10. Chen, Q., K.-M. Huang, X. Yang, M. Luo, and H. Zhu, "An artificial nerve network realization in the measurement of material permittivity," Progress In Electromagnetics Research, Vol. 116, 347-361, 2011.
11. Matvejev, V., C. de Tandt, W. Ranson, J. Stiens, R. Vounckx, and D. Mangelings, "Integrated waveguide structure for highly sensitive THz spectroscopy of nano-liter liquids in capillary tubes," Progress In Electromagnetics Research, Vol. 121, 89-101, 2011.
12. Belyakov, E. V., "High-quality resonance in a waveguide with a highly-absorbing dielectric," Elektronnaya Tekhnika. Ser. Elektronika SVCh (Electronic Engineering), Vol. 393, No. 9, 3-5, 1986.
13. Bakaushina, G. F., E. V. Belyakov, N. B. Zinov'eva, and A. M. Khrapko, "UHF-analyzer of concentration of liquid pharmaceutical substances," Elektronnaya Tekhnika. Ser. Elektronika SVCh (Electronic Engineering), Vol. 393, No. 9, 54-56, 1986.
14. Belyakov, E. V., "A resonant UHF dielcometer for absorbing liquids," Elektronnaya Tekhnika. Ser. Elektronika SVCh (Electronic Engineering), Vol. 401, No. 7, 51-53, 1987.
15. Belyakov, E. V., "Tunable UHF-resonator for measuring absorbing liquids," Elektronnaya Tekhnika. Ser. Elektronika SVCh (Electronic Engineering), Vol. 424, No. 10, 59-61, 1989.
16. Kirichenko, A. Y., V. I. Lutsenko, Y. F. Filippov, Y. V. Prokopenko, and E. V. Krivenko, "Temperature-dielectric spectroscopy of aqueous solutions using the method of capillary-waveguide resonance," Izv. VUZov. Radiofizika, Vol. 51, No. 8, 711-716, 2008.
17. Bludov, Y. V., "Propagation of the H10 mode in a rectangular waveguide with a dielectric discontinuity," Tech. Phys., Vol. 50, No. 8, 1062-1068, 2005.
18. Malyshenko, Y. I., V. L. Kostina, and A. N. Roenko, "A model of water dielectric permittivity in microwave and terahertz ranges," Ukr. J. Phys., Vol. 52, No. 2, 155-161, 2007.
19. Furashov, N. I., V. E. Dudin, and B. A. Sverdlov, "Study of the dielectric properties of water in the frequency band 75-120 GHz," Izv. VUZov. Radiofizika, Vol. 49, No. 6, 489-501, 2006.
20. Born, M. and E. Wolf, Principles of Optics, 7th edition, Cambridge, 2003.