Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-02T18:55:41.615Z Has data issue: false hasContentIssue false
  • English
  • Français

Mid-infrared silicon photonics for sensing applications

Published online by Cambridge University Press:  28 May 2012

Goran Z. Mashanovich ,
Milan M. Milosevic ,
Milos Nedeljkovic ,
David Cox ,
Vittorio M. N. Passaro ,
Harold M. H. Chong  and
Richard Soref
Goran Z. Mashanovich
Affiliation:
School of Electronics and Computer Science, University of Southampton, Southampton, UK*
Milan M. Milosevic
Affiliation:
Advanced Technology Institute, University of Surrey, Guildford, Surrey, UK
Milos Nedeljkovic
Affiliation:
School of Electronics and Computer Science, University of Southampton, Southampton, UK*
David Cox
Affiliation:
Advanced Technology Institute, University of Surrey, Guildford, Surrey, UK
Vittorio M. N. Passaro
Affiliation:
Dipartimento di Elettrotecnica ed Elettronica, Politecnico di Bari, 70125 Bari, Italy
Harold M. H. Chong
Affiliation:
School of Electronics and Computer Science, University of Southampton, Southampton, UK*
Richard Soref
Affiliation:
Physics and Engineering Departments, University of Massachusetts at Boston, Boston, MA 02125 USA
Get access

Abstract

The mid-infrared wavelength region offers a plethora of possible applications ranging from sensing, medical diagnostics and free space communications, to thermal imaging and IR countermeasures. Hence group IV mid-infrared photonics is attracting more research interest lately. Sensing is an especially attractive area as fundamental vibrations of many important gases are found in the 3 to 14 μm spectral region. To realise group IV photonic mid-infrared sensors several serious challenges need to be overcome. The first challenge is to find suitable material platforms for the mid-infrared. In this paper we present experimental results for passive mid-infrared photonic devices realised in silicon-on-insulator (SOI), silicon-on-sapphire (SOS), and silicon on porous silicon (SiPSi). Although silicon dioxide is lossy in most parts of the mid-infrared, we have shown that it has potential to be used in the 3-4 μm region. We have characterized SOI waveguides with < 1 dB/cm propagation loss. We have also designed and fabricated SOI passive devices such as MMIs and ring resonators. For longer wavelengths SOS or SiPSi structures could be used. An important active device for long wavelength group IV photonics will be an optical modulator. We present relationships for the free-carrier induced electro-refraction and electro-absorption in silicon in the mid-infrared wavelength range. Electro-absorption modulation is calculated from impurity-doping spectra taken from the literature, and a Kramers-Kronig analysis of these spectra is used to predict electro-refraction modulation. We have examined the wavelength dependence of electro-refraction and electro-absorption, and found that the predictions suggest longer-wave modulator designs will in many cases be different than those used in the telecom range.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1437: Symposium L – Group IV Photonics for Sensing and Imaging , 2012 , mrss12-1437-l02-03
Copyright
Copyright © Materials Research Society 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1] Soref, R.A., “Mid-infrared photonics in silicon and germanium,” Nature Photonics vol. 4, pp. 495–497, Aug. 2010.Google Scholar
[2] Soref, R.A., “Towards silicon-based longwave integrated optoelectronics,” Proc. SPIE vol. 6898, pp. 6898–09, Jan. 2008.Google Scholar
[3] Soref, R. A., Emelett, S. J., and Buchwald, W. R., “Silicon waveguided components for the long-wave infrared region,” J. Opt. A (U.K.), Pure Appl. Opt., vol. 8, pp.840–848, Aug. 2006.Google Scholar
[4] Milošević, M. M., Thomson, D. J., Chen, X., Cox, D., and Mashanovich, G. Z., “Silicon waveguides for the 3-4 μm wavelength range,” 8th IEEE Group IV Photonics conference, London, UK, 14-16 September 2011.Google Scholar
[5] Baehr-Jones, T., Spott, A., Ilic, R., Penkov, B., Asher, W., and Hochberg, M., “Silicon-on-sapphire integrated waveguides for the mid-infrared,” Opt Express, vol. 18, no. 12, pp. 12127–12135, Jun. 2010.Google Scholar
[6] Li, F., Jackson, S., Grillet, C., Magi, E., Hudson, D., Madden, S. J., Moghe, Y., O’Brien, C., Read, A., Duvall, S. G., Atanackovic, P., Eggleton, B. J. and Moss, D., “Low propagation loss silicon-on-sapphire waveguides for the mid-infrared,” Opt Express, vol. 19, no. 16, pp. 15212–15220, Aug. 2011.Google Scholar
[7] Spott, A., Liu, Y., Baehr-Jones, T., Ilic, R., and Hochberg, M., “Silicon waveguides and ring resonators at 5.5μm,” Appl. Phys. Lett., vol. 97, no. 21, pp. 213501, Nov. 2010.Google Scholar
[8] Mashanovich, G. Z., Milošević, M. M., Nedeljkovic, M., Owens, N., Xiong, B., Teo, E. J., and Hu, Y., “Low loss silicon waveguides for the mid-infrared,” Opt Express, vol. 19, no. 8, pp. 7112–7119, Mar. 2011.Google Scholar
[9] Wei, Y., Li, G., Hao, Y., Li, Y., Yang, J., Wang, M. and Jiang, X., “Long-wave infrared 1 x 2 MMI based on air-gap beneath silicon rib waveguides,” Opt. Express, vol. 19, no. 17, pp. 15803–15809, Aug. 2011.Google Scholar
[10] Milošević, M. M., Matavulj, P. S., Yang, P.Y., Bagolini, A. and Mashanovich, G. Z., “Rib waveguides for mid-infrared silicon photonics,” J. Opt. Soc. Am. B, vol. 26, no. 9, pp. 1760–1766, Sep. 2009.Google Scholar
[11] Nedeljkovic, M., Soref, R. A. and Mashanovich, G. Z., “Free-carrier electro-absorption and electro-refraction modulation in group IV materials at mid-infrared wavelengths,” Proc. SPIE 8266, 82660Y, Jan. 2012.Google Scholar
[12] Soref, R. A. and Bennett, B. R., “Electrooptical effects in silicon,” IEEE J. Quantum Electronics., vol. 23, no. 1, pp. 123–129, Jan. 1987.Google Scholar
[13] Reed, G. T., Mashanovich, G., Gardes, F. Y., Thomson, D. J., “Silicon optical modulators,” Nature Photonics, vol. 4, pp. 518–526, Aug. 2010.Google Scholar
[14] Thomson, D. J., Gardes, F. Y., Hu, Y., Mashanovich, G., Fournier, M., Grosse, P., Fedeli, J-M., and Reed, G. T., “High contrast 40Gbit/s optical modulation in silicon,” Opt Express, vol. 19, no.12, pp. 11507–11516, Jun. 2011.Google Scholar
[15] Gardes, F. Y., Thomson, D. J., Emerson, N. G., and Reed, G. T., “40 Gb/s silicon photonics modulator for TE and TM polarisations,” Opt Express, vol. 19, no. 12, pp. 11804–111814, Jun. 2011.Google Scholar
[16] Collocott, S. J. and Troup, G.J., “Adaptation: numerical solution of the Kramers-Kronig transforms by trapezoidal summation as compared to a Fourier method,” Computer Physics Communications, vol. 17, pp. 393–395, 1979.Google Scholar
[17] Nedeljkovic, M., Soref, R. A. and Mashanovich, G. Z., “Free-carrier electro-absorption and electro-refraction modulation predictions for silicon over the 1-14 μm infrared wavelength range,” IEEE Photonics Journal, vol. 3, no. 6, pp. 1171–1180, Dec. 2011.Google Scholar
[18] Huang, H. C., Yee, S. and Soma, M., “Quantum calculations of the change in refractive index due to free carriers in silicon with nonparabolic band structure,” J. Appl. Phys. 67(4), 2033–2039 (1990).Google Scholar
[19] Kahn, A. H., “Theory of the infrared absorption of carriers in germanium and silicon,” Phys. Rev. 97(6), 1647–1652 (1954).Google Scholar
[20] Soref, R. A. and Friedman, L., “Electro-optical modulation in Si1-xGex/Si and related heterostructures,” International Journal of Optoelectronics 9(2), 205–210 (1994).Google Scholar