Skip to main content
Log in

Behaviour of Poynting vector for dielectric-metal-dielectric optical waveguides and applications

  • Published:
Optical and Quantum Electronics Aims and scope Submit manuscript

Abstract

In this paper, we derive analytical expressions for the spatial evolution of the instantaneous Poynting vector for the transverse magnetic (TM) surface plasmon (SP) modes of a symmetric planar dielectric-metal-dielectric optical waveguide. We discuss the behaviour of the Poynting vector in the metal film due to the optical absorption of electromagnetic waves propagating through the medium to excite the surface plasmons in a resonant manner in the metal film at the interface. This optical absorption of the electromagnetic waves results in a finite propagation length of SP modes. We derive an analytical formula for the penetration depth of the instantaneous Poynting vector in the dielectric cladding regions and show that it is different as compared to the penetration depth of the average Poynting vector. We utilize this analytical formula to calculate the optimum thickness of the affinity layer in a graphene-based surface plasmon resonance (SPR) biosensor and analyze its performance in terms of sensitivity and Figure-of-Merit. We also show that our analytical formula can be used to calculate the optimum thickness of a thin high-index dielectric layer which is added to any conventional SPR based sensor to enhance its sensitivity. The optimum thickness thus calculated correlates closely with the experimental results that have been published previously. The analysis done in this paper can also be utilized in calculating the separation between any two adjacent waveguides/optical films which are coupled together evanescently, such as directional couplers and TE/TM polarisers.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10

Similar content being viewed by others

Availability of data and material

Available with the corresponding author.

Code availability

Available with the corresponding author.

References

Download references

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Author information

Authors and Affiliations

Authors

Contributions

JKA contributed to the original idea, supervised the study, and contributed to language improvement. HK developed the software using MATLAB for simulation and data analysis; prepared the manuscript and generated the figures.

Corresponding author

Correspondence to Jagneet Kaur Anand.

Ethics declarations

Conflict of interest

The authors declare no competing interests.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Anand, J.K., Kushwah, H. Behaviour of Poynting vector for dielectric-metal-dielectric optical waveguides and applications. Opt Quant Electron 52, 410 (2020). https://doi.org/10.1007/s11082-020-02519-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s11082-020-02519-x

Keywords

Navigation