Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-24T16:15:15.940Z Has data issue: false hasContentIssue false

Exploiting the Metal-Insulator Transition of VO2 Thin Films for Terahertz Wave Modulation and Switching

Published online by Cambridge University Press:  11 June 2015

Md Nadim Ferdous Hoque
Affiliation:
Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock, Texas 79409, USA
Gulten Karaoglan-Bebek
Affiliation:
Department of Physics and Nano Tech Center, Texas Tech University, Lubbock, Texas 79409, USA
Mark Holtz
Affiliation:
Department of Physics and MSEC, Texas State University, San Marcos, Texas 78666, USA
Ayrton A. Bernussi
Affiliation:
Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock, Texas 79409, USA
Zhaoyang Fan
Affiliation:
Department of Electrical and Computer Engineering and Nano Tech Center, Texas Tech University, Lubbock, Texas 79409, USA
Get access

Abstract

VO2 is one of the very few natural materials that can be used to modulate terahertz (THz) radiations. A 100-nm thick VO2, when in its metallic phase, has a charge density of more than ∼ 1015 cm-2 which will strongly reflect and absorb the THz radiation; while in its insulator state, the charge density is lowered by several orders of magnitude to be THz transparent. Therefore, exploiting the metal-insulator transition of VO2 is a potential approach to modulate or even switch THz radiation for THz optics. Here we report that VO2 epitaxial thin films on sapphire substrate exhibits 85% amplitude modulation depth in a broad bandwidth, while this value can be improved to 95% when VO2 film is coated on both sides of a substrate. We further demonstrate that with wafer bonding, 4-layered VO2 thin films exhibit a transmittance as low as -20 dB to -30 dB at their metallic state, enough for switching applications. We also report our proof-of-concept demonstration of THz spatial light modulator that exhibits amplitude modulation as large as 96%, -30 dB pixel-to-pixel crosstalk, and a broad THz bandwidth.

Type
Articles
Copyright
Copyright © Materials Research Society 2015 

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

Chen, C. and Fan, Z., Appl. Phys. Lett. 95, 262106 (2009).CrossRefGoogle Scholar
Nazari, M., Zhao, Y., Kuryatkov, V. V., Fan, Z. Y., Bernussi, A. A., and Holtz, M., Phys. Rev. B 87, 035142 (2013).CrossRefGoogle Scholar
Zhang, J. and Averitt, R., Ann. Rev. Mater. Res. 44, 19 (2014).CrossRefGoogle Scholar
Zhao, Y., Karaoglan-Bebek, G., Pan, X., Holtz, M., Bernussi, A.A., and Fan, Z., Appl. Phys. Lett. 104, 241901 (2014).10.1063/1.4884077CrossRefGoogle Scholar
Chen, C., Zhu, Y., Zhao, Y., Lee, J.H., Wang, H., Bernussi, A., Holtz, M., and Fan, Z., Appl. Phys. Lett. 97, 211905 (2010).CrossRefGoogle Scholar
Zhang, Y., Qiao, S., Sun, L., Shi, Q. W., Huang, W., Li, L., and Yang, Z., Opt. Express 22, 11070 (2014).CrossRefGoogle Scholar
Zhu, Y., Vegesna, S., Zhao, Y., Kuryatkov, V., Holtz, M., Fan, Z., Saed, M., and A Bernussi, A., Opt. Lett. 38, 2382 (2013).10.1364/OL.38.002382CrossRefGoogle Scholar
Jeong, Y.-G., Bernien, H., Kyoung, J.-S., Park, H.-R., Kim, H. S., Choi, J.-W., et al., Opt. Express 19, 21211 (2011).CrossRefGoogle Scholar
Fan, F., Hou, Y., Jiang, Z.-W., Wang, X.-H., and Chang, S.-J., Appl. Optics 51, 4589 (2012).10.1364/AO.51.004589CrossRefGoogle Scholar
Chan, W. L., Chen, H.-T., Taylor, A. J., Brener, I., Cich, M. J., and Mittleman, D. M., Appl. Phys. Lett. 94, 213511 (2009).10.1063/1.3147221CrossRefGoogle Scholar
Hoque, M. N. F., Karaoglan-Bebek, G., Holtz, M., Bernussi, A. A., and Fan, Z., Opt. Comm. 350, 309 (2015).CrossRefGoogle Scholar
Zhao, Y., Lee, J. H., Zhu, Y., Nazari, M., Chen, C., Wang, H., Bernussi, A., Holtz, M., and Fan, Z., J. Appl. Phys. 111, 053533 (2012).CrossRefGoogle Scholar
Zhu, Y., Zhao, Y., Holtz, M., Fan, Z., and Bernussi, A. A., J. Opt. Soc. Am. B 29, 2373 (2012).CrossRefGoogle Scholar