Multispectral Superconducting Nanowire Single-Photon Detector Based on Thickness-Modulated Optical Film Stack

Abstract

We report on a multispectral superconductingphoton detector based on a thickness-modulated optical film stack. This unique optical film structure provides a modulated reflection bands used for single-photon detection in well-separated multiple wavelength ranges. The fabricated detector shows four detection bands with the system detection efficiencies of 76.2%, 76.9%, 81.3%, and 85.0% at the wavelengths of 505, 610, 1030, and 1550 nm, respectively. A 4-pixel multispectral detector array is then demonstrated, and a photon flux reconstruction experiment is performed to reconstruct the photon flux at the wavelengths of interest. The present multispectral detector enriches the available optical architectures and may have interesting multispectral applications such as multispectral ranging or imaging.

Multispectral SNSPD Using a Modified Distributed Bragg Reflector, Gold Mirror, and Multilayer-Nanowire Structures

“…Early work into the development of multispectral or broadband SNSPDs has shown promising results in achieving high SDE across specific wavelength ranges, through strategies such as utilizing a single nanowire layer in conjunction with a special dielectric stack, which generates distinct reflected waves on the mirror surface that results in multiple absorption resonances [11,12]. Furthermore, employing multiple nanowire layers atop mirror structures has also been explored to enhance the overall SDE [13][14][15].…”

“…Nevertheless, many reported detectors are still limited in terms of bandwidth, exhibiting high SDE across a bandwidth of typically a few hundred nanometers around a single resonant wavelength, preventing SNSPDs from fully exploiting the potential of broader wavelength ranges. To extend the detection bandwidth, recent efforts in developing broadband or multispectral SPSNDs have taken advantage of multiple optical absorption resonances [11,12] or multilayer-nanowire structures [13][14][15], thus extending the detection bandwidth, and providing solutions for a wider range of applications, such as fluorescence correlation spectroscopy [16], singlet oxygen luminescence detection [17], as well as ranging and imaging [18,19].…”