INVESTIGATION OF THE SPECTRUM OF ZN I ATOMS IN THE TRIPLET RYDBERG STATES

• Дата: 2021
• Автори: Pogrebnyak, N. I., Dyubko, S. F., Perepechai, M. P., Kutsenko, A. S.
• Формат: Стаття
• Мова: Ukrainian
• Опубліковано: Видавничий дім «Академперіодика» 2021
• Теми: zinc atom; triplet states of atoms; Rydberg states; laser excitation; microwave radiation
• Онлайн доступ: http://rpra-journal.org.ua/index.php/ra/article/view/1365
• Назва журналу: Radio physics and radio astronomy

Purpose: This work aims at investigating the zinc atoms in the triplet preionization – Rydberg states. The energy levels of atoms having two electrons outside the closed shell were studied mainly by the optical spectroscopy methods. However, just using the microwave spectroscopy to measure the frequency of transitions between the two Rydberg states allows to increase the accuracy of measurements in two or more orders of magnitude.Disign/methodology/approach:A line of three dye lasers is used to excite the zinc atoms into the triplet Rydberg states with a predetermined set of quantum numbers. The radiation of the first two of them is transformed into the second harmonic in nonlinear crystals. Dye lasers are excited by the radiation of the second harmonic of one YAG: ND3+ laser. All three radiations are reduced to the zone of interaction with the laser and the microwave radiation, which is located between the plates of the ionization cell, where the pulsed electric field is created. The excited Rydberg atoms are recorded with the field ionization procedure. The beam of neutral atoms is created by an effusion cell under the vacuum conditions, the residual pressure does not exceed 10-5 mm Hg. A pulsed electric field of some certain intensity results inionization of atoms excited by microwave radiation and in acceleration of electrons, which have appeared in the direction of the secondary electron multiplier, though being insufficient for ionization of atoms excited only by the laser radiation and which are initial for interaction with microwaves. By scanning the microwave radiation frequency with the given step and measuring the signal intensity of the secondary electron multiplier, the excitation spectrum of the atoms under study can be obtained.Findings: Using the created laser-microwave spectrometer, the frequencies of the F→D, F→F and F→G  transitions between the triplet Rydberg states of zinc atoms were measured. From the analysis made of the transition frequencies, the quantum defect decomposition constants were obtained by the Ritz formula for the D, F, and G states of zinc atoms. Conclusions: The frequencies of the F→D, F→F and F→G  transitions between the triplet Rydberg states of zinc atoms were measured that allowed obtaining the quantum defect decomposition constants according to the Ritz formula for the D, F and G states of zinc atoms, that in turn had allowed to calculate the energy of these terms and the transition frequencies at least in two orders of magnitude more accurately as against the similar measurements made by the optical spectroscopy.Key words: zinc atom, triplet states of atoms, Rydberg states, laser excitation, microwave radiationManuscript submitted  17.06.2021Radio phys. radio astron. 2021, 26(3): 256-269REFERENCES1. BIEMONT, E. and GODEFROID, M., 1980. A Reassessment of the Zinc Solar Abundance. Astron. Astrophys. vl. 84, no. 3, p. 361–363.2. SNEDEN, C., GRATTON, R. G. and CROCKER, D. A., 1991. Trends in copper and zinc abundances for disk and halo stars. Astron. Astrophys. vol. 246, no. 2, pp. 354–367.3. BROWN, C. M. and TILFORD, S. G., 1975. Absorption spectra of Zn i and Cd i in the 1300–1750 Å region. J. Opt. Soc. Am. vol. 65, is. 12, pp. 1404–1409. DOI: https://doi.org/10.1364/JOSA.65.0014044. GULLBERG, D. and LITZEN, U., 2000. Accurately measured wavelengths of Zn I and Zn II Lines of Astrophysical interest. Phys. Scr. vol. 61, no. 6, pp. 652–656. DOI: https://doi.org/10.1238/Physica.Regular.061a006525. COMMENTS.UA., 2021. What diseases cause zinc deficiency in the body. [online] (in Rusian). [viewed 9 June 2021]. Available from: https://health.comments.ua/ua/news/vitamins-and-nutritional-supplements/yaki-zahvoryuvannya-viklikae-deficit-cinku-v-organizmi-676087.html6. NIST., 2021. Atomic Spectra Database [online]. [viewed 9 June 2021]. Available from: http://physics.nist.gov/asd7. ESHKOBILOV, N. B., 2000. Laser spectroscopy of the Rydberg states of atoms group IIB (Zn, Cd, Hg). J. Appl. Spectrosc. vol. 67, no. 2, pp. 343–345. DOI: https://doi.org/10.1007/BF026818568. NADEEM, A., NAWAZ, M., BHATTI, S. A., and BAIG, M. A., 2006. Multi-step laser excitation of the Highly excited states of zinc. Opt. Commun. Vol. 259, Is. 2, pp. 834–839. DOI: https://doi.org/10.1016/j.optcom.2005.08.0759. NAWAZ, M., NADEEM, A., BHATTI, S. A. and BAIG, M. A., 2006. Two-step laser excitation of 4snd 3D1,2,3 and 4sns 3S1 states from the 4s4p 3P levels in zinc. J. Phys. B: At. Mol. Opt. Phys. vol 39, no. 4, pp. 871–882. DOI: https://doi.org/10.1088/0953-4075/39/4/01110. SUGAR, J. and MUSGROVE, A., 1995. Energy levels of Zinc, Zn I through Zn XXX. J. Phys. Chem. Ref. Data. vol. 24, no. 6, pp. 1803–1872. DOI: https://doi.org/10.1063/1.55597111. KUTSENKO, A. S., MACADAM, K. B., DYUBKO, S. F. and POGREBNYAK, N.L., 2015. Millimeter-wave spectroscopy of Zn I in 1D2, 1F3 and 1G4 Rydberg states. J. Phys. B: At. Mol. Opt. Phys. vol. 48, no. 24, id. 245005. DOI: https://doi.org/10.1088/0953-4075/48/24/24500512. POGREBNYAK, N. L., DYUBKO, S. F., ALEKSEEV, E. A., PEREPECHAI, M. P., TKACHEV, A. I. and VLASENKO, S. A., 2019. Laser-microwave spectrometer and spectroscopy of zinc atom in triplet rydberg states. Radio Phys. Radio Astron. vol. 24, no. 4. pp. 272–284. (in Ukrainian). DOI: https://doi.org/10.15407/rpra24.04.27213. GALLAGHER, T. F., 1994. Rydberg Atoms. New York: Cambridge University Press. DOI: https://doi.org/10.1017/CBO978051152453014. CIVIŠ, S., FERUS, M., CHERNOV, V. E., ZANOZINA, E. M. and JUHA, L., 2014. Zn I spectra in the 1300-6500 cm-1 range. J. Quant. Spectrosc. Radiat. Transf. vol. 134, pp. 64–73. DOI: https://doi.org/10.1016/j.jqsrt.2013.10.01715. GULLBERG, D. and LITZÉN, U., 2000. Accurately Measured Wavelengths of Zn I and Zn II Lines of Astrophysical Interest. Phys. Scr. vol. 61, no. 6, pp. 652–656. DOI: https://doi.org/10.1238/Physica.Regular.061a0065216. MUNTENBRUCH, H., 1960. Die vervollständigung des termschemas von Zn I mit hilfe einer hohlkathodenentladung. Spectrochimica Acta. vol. 16, is. 9, pp. 1040–1053, E5-E6. DOI: https://doi.org/10.1016/0371-1951(60)80144-017. KOMPITSAS, M., BAHARIS, C. and PAN, Z., 1994. Rydberg states of zinc and measurement of the dipole polarizability of the Zn+ ion. J. Opt. Soc. Am. B. vol. 11, no. 5, pp. 697–702. DOI: https://doi.org/10.1364/JOSAB.11.00069718. DYUBKO, S. F., EFREMOV, V. A., GERASIMOV, V. G. and MACADAM, K. B., 2003. Microwave spectroscopy of Al I Rydberg states: F terms. J. Phys. B: At. Mol. Opt. Phys. vol. 36, no. 18, pp. 3797–3804. DOI: https://doi.org/10.1088/0953-4075/36/18/30819. SHAH, M., AISHA, G., SHAHZADA, S., HAQ, S. U. and NADEEM, A., 2018. Step-Wise Laser Excitation of the 4snf 3F Rydberg States of Neutral Zinc. Spectrosc. Lett. vol. 51, is. 1, pp. 1–6. DOI: https://doi.org/10.1080/00387010.2017.1357636