Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Research Highlight
  • Published:

MID-INFRARED OPTICS

On-chip spectroscopy

Nature Photonics volume 12, page 189 (2018)Cite this article

Access through your institution
Buy or subscribe

APL Photon. 3, 021301 (2018)

Spontaneous parametric down-conversion (SPDC) spectroscopy is attracting attention as it offers a means for performing mid-infrared (mid-IR) spectroscopy without the need for dedicated sources and detectors in the mid-IR, which can be expensive and are limited in performance. Instead, the scheme harnesses the principles of nonlinear optics to split a short-wavelength pump photon into a pair of photons (a long-wavelength (mid-IR) idler photon and a short-wavelength signal (visible or IR) photon) using a nonlinear crystal. Correlations between the signal and idler photons mean that collecting information about one also provides information about the other. As a result, the short-wavelength signal photon can be read out using affordable, high-performance detection equipment while the mid-IR idler photons probe the sample. To date, demonstrations of the technique have relied on the use of bulk nonlinear crystals, but scientists in Australia and Germany have now shown that it should be possible to create an integrated on-chip version using lithium niobate waveguides to perform the SPDC. Their experiments with pump wavelengths in the 740–780 nm range and Ti-diffused LiNbO3 waveguides suggest that idler wavelengths as long as 2.5 μm can be generated. An on-chip system employing such waveguides would not only be compact but should also offer a high SPDC efficiency of up to 9 × 106 photon pairs per second for just 0.5 mW of pump power .

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Access through your institution

Buy this article

  • Purchase on SpringerLink
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Author information

Authors and Affiliations

  1. Nature Photonics https://www.nature.com/naturephotonics

    Oliver Graydon

Authors
  1. Oliver Graydon
    View author publications

    Search author on:PubMed Google Scholar

Corresponding author

Correspondence to Oliver Graydon.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Graydon, O. On-chip spectroscopy. Nature Photon 12, 189 (2018). https://doi.org/10.1038/s41566-018-0149-9

Download citation

  • Published:

  • Issue date:

  • DOI: https://doi.org/10.1038/s41566-018-0149-9

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing