Advertisement

Optical Review

, Volume 25, Issue 2, pp 205–214 | Cite as

Mechanisms of the anomalous Pockels effect in bulk water

  • Shunpei Yukita
  • Yuto Suzuki
  • Naoyuki Shiokawa
  • Takayoshi Kobayashi
  • Eiji Tokunaga
Regular Paper
  • 115 Downloads

Abstract

The “anomalous” Pockels effect is a phenomenon that a light beam passing between two electrodes in an aqueous electrolyte solution is deflected by an AC voltage applied between the electrodes: the deflection angle is proportional to the voltage such that the incident beam alternately changes its direction. This phenomenon, the Pockels effect in bulk water, apparently contradicts what is believed in nonlinear optics, i.e., macroscopic inversion symmetry should be broken for the second-order nonlinear optical effect to occur such as the first-order electro-optic effect, i.e., the Pockels effect. To clarify the underlying mechanism, the dependence of the effect on the electrode material is investigated to find that the Pockels coefficient with Pt electrodes is two orders of magnitude smaller than with indium tin oxide (ITO) electrodes. It is experimentally confirmed that the Pockels effect of interfacial water in the electric double layer (EDL) on these electrodes shows an electrode dependence similar to the effect in bulk water while the effects depend on the frequency of the AC voltage such that the interfacial signal decreases with frequency but the bulk signal increases with frequency up to 221 Hz. These experimental results lead to a conclusion that the beam deflection is caused by the refractive index gradient in the bulk water region, which is formed transiently by the Pockels effect of interfacial water in the EDL when an AC electric field is applied. The refractive index gradient is caused by the diffuse layer spreading into the bulk region to work as a breaking factor of inversion symmetry of bulk water due to its charge-biased ionic distribution. This mechanism does not contradict the principle of nonlinear optics.

Keywords

Pockels effect Electro-optic effect Water Sagnac interferometer Electric double layer Diffuse layer ITO Pt 

Notes

Acknowledgements

The authors would like to thank Prof. Kiyoshi Asakawa and Prof. Yasuhiro Horiike from University of Tsukuba for their valuable comments. This work was supported by a Grant-in-Aid for Scientific Research(C) (Grant Number JP15K05134), Japan Society for the Promotion of Science (JSPS).

Compliance with ethical standards

Conflicts of interest

There are no conflicts of interest to declare.

References

  1. 1.
    Yariv, A.: Quantum Electronics, 3rd edn. Wiley, New York (1988)Google Scholar
  2. 2.
    Chen, W., Feller, M.B., Shen, Y.R.: General considerations on optical second-harmonic generation from surfaces and interfaces. Phys. Rev. B 33, 8254 (1986)ADSCrossRefGoogle Scholar
  3. 3.
    Gragson, D.E., McCarty, B.M., Richmond, G.L.: Ordering of interfacial water molecules at the charged air/water interface observed by vibrational sum frequency generation. J. Am. Chem. Soc. 119, 6144–6152 (1997)CrossRefGoogle Scholar
  4. 4.
    Wen, Y.-C., Zha, S., Liu, X., Yang, S., Guo, P., Shi, G., Fang, H., Shen, Y.R., Tian, C.: Unveiling microscopic structures of charged water interfaces by surface-specific vibrational spectroscopy. Phys. Rev. Lett. 116, 016101 (2016)ADSCrossRefGoogle Scholar
  5. 5.
    Tokunaga, E., Nosaka, Y., Hirabayashi, M., Kobayashi, T.: Pockels effect of water in the electric double layer at the interface between water and transparent electrode. Surf. Sci. 601, 735 (2007)ADSCrossRefGoogle Scholar
  6. 6.
    Nosaka, Y., Hirabayashi, M., Kobayashi, T., Tokunaga, E.: Gigantic optical Pockels effect in water within the electric double layer at the electrode-solution interface. Phys. Rev. B. 77, 241401(R) (2008)ADSCrossRefGoogle Scholar
  7. 7.
    Kanemaru, H., Nosaka, Y., Hirako, A., Ohkawa, K., Kobayashi, T., Tokunaga, E.: Electrooptic effect of water in electric double layer at interface of GaN electrode. Opt. Rev. 17, 352 (2010)CrossRefGoogle Scholar
  8. 8.
    Suzuki, Y., Osawa, K., Yukita, S., Kobayashi, T., Tokunaga, E.: Anomalously large electro-optic Pockels effect at the air–water interface with an electric field applied parallel to the interface. Appl. Phys. Lett. 108, 191103 (2016)ADSCrossRefGoogle Scholar
  9. 9.
    Grahame, D.C.: The electrical double layer and the theory of electrocapillarity. Chem. Rev. 41, 441 (1947)CrossRefGoogle Scholar
  10. 10.
    Brown Jr., G.E., Henrich, V.E., Casey, W.H., Clark, D.L., Eggleston, C., Felmy, A., Goodman, D.W., Grätzel, M., Maciel, G., McCarthy, M.I., Nealson, K.H., Sverjensky, D.A., Toney, M.F., Zachara, J.M.: Metal oxide surfaces and their interactions with aqueous solutions and microbial organisms. Chem. Rev. 99, 77 (1999)CrossRefGoogle Scholar
  11. 11.
    Yukita, S., Shiokawa, N., Kanemaru, H., Namiki, H.: Takayoshi Kobayashi, Deflection switching of a laser beam by the Pockels effect of water. Appl. Phys. Lett. 100, 171108 (2012)ADSCrossRefGoogle Scholar
  12. 12.
    Gabriel, M.C., Whitaker Jr., N.A., Dirk, C.W., Kuzyk, M.G., Thakur, M.: Measurement of ultrafast optical nonlinearities using a modified Sagnac interferometer. Opt. Lett. 16(17), 1334 (1991)ADSCrossRefGoogle Scholar
  13. 13.
    Shiokawa, N., Tokunaga, E.: Quasi first-order Hermite Gaussian beam for enhanced sensitivity in Sagnac interferometer photothermal deflection spectroscopy. Opt. Express 24(11), 11961 (2016)ADSCrossRefGoogle Scholar
  14. 14.
    Misawa, K., Kobayashi, T.: Femtosecond Sagnac interferometer for phase spectroscopy. Opt. Lett. 20, 1550–1552 (1995)ADSCrossRefGoogle Scholar
  15. 15.
    Takahashi, T., Ishii, Y., Onodera, R.: Phase-shifting interferometric profilometry with a wavelength-tunable diode source. Opt. Rev. 21(3), 410 (2014)CrossRefGoogle Scholar
  16. 16.
    Toney, M.F., et al.: Near-surface alignment of polymers in rubbed films. Nature 374, 709 (1995)ADSCrossRefGoogle Scholar
  17. 17.
    Ho, P.P., Alfano, R.R.: Optical Kerr effect in liquids. Phys. Rev. A 20, 2170 (1979)ADSCrossRefGoogle Scholar
  18. 18.
    Dworczak, R., Kieslinger, D.: Electric Deld induced second harmonic generation (EFISH) experiments in the swivel cell: new aspects of an established method. Phys. Chem. Chem. Phys. 2, 5057–5064 (2000)CrossRefGoogle Scholar
  19. 19.
    Fricke, H.: The theory of electrolytic polarization. Philos. Mag. 14, 310 (1932)CrossRefGoogle Scholar
  20. 20.
    Born, M., Wolf, E.: Principles of Optics, 6th edn. Pergamon Press, Oxford (1980)Google Scholar
  21. 21.
    Kobiyama, M.: Theory of Optical Thin Films, vol. 2, p. 83. Optronics, Tokyo (2003)Google Scholar
  22. 22.
    Morrow, R., McKenzie, D.R., Bilek, M.M.M.: The time-dependent development of electric double-layers in saline solutions. J. Phys. D Appl. Phys. 39, 937–943 (2006)ADSCrossRefGoogle Scholar
  23. 23.
    Little, C.A.E., Orloff, N.D., Hanemann, I.E., Long, C.J., Bright, V.M., Booth, J.C.: Modeling electrical double-layer effects for microfluidic impedance spectroscopy from 100 kHz to 110 GHz. Lab. Chip 17, 2674–2681 (2017)CrossRefGoogle Scholar
  24. 24.
    Kanemaru, H., Yukita, S., Namiki, H., Nosaka, Y., Kobayashi, T., Tokunaga, E.: Giant Pockels effect of polar organic solvents and water in the electric double layer on a transparent electrode. RSC Advs. 7, 45682–45690 (2017)CrossRefGoogle Scholar
  25. 25.
    Sopra, S.A., Optical Data from Sopra SA. http://www.sspectra.com/sopra.html. Accessed 5 Jan 2018

Copyright information

© The Optical Society of Japan 2018

Authors and Affiliations

  1. 1.Department of Physics, Faculty of ScienceTokyo University of ScienceShinjuku-kuJapan
  2. 2.Research Center for Water Frontier Science and TechnologyTokyo University of ScienceShinjuku-kuJapan
  3. 3.Advanced Ultrafast Laser Research Center and Brain Science Inspired Life Support Research CenterThe University of Electro-CommunicationsChofuJapan
  4. 4.Advanced Ultrafast Laser Research Center, Department of ElectrophysicsNational Chiao-Tung UniversityHsinchuTaiwan

Personalised recommendations