Flexible Optical Design Method for Superconducting Nanowire Single-Photon Detectors
October 25, 2016 | NICTEstimated reading time: 2 minutes
The National Institute of Information and Communications Technology has succeeded in the development of flexible optical design method for superconducting nanowire single-photon detectors (SSPDs or SNSPDs).
This technique enables SSPDs with a broadband high detection efficiency reject a specific wavelength, and is effective for multidisciplinary applications in fields such as the quantum cryptography, fluorescence spectroscopy, and remote sensing that require high efficiency over a precise spectral range and strong signal rejection at other wavelengths.
This achievement appeared in the Scientific Reports on October 24, 2016 ("Superconducting nanowire single-photon detectors with non-periodic dielectric multilayers"). The reported results have been partially obtained as a part of JST-SENTAN program and AMED-SENTAN program from April 2015.
Achievements
We have developed SSPDs on dielectric multilayers and their optical design method, which enable us to design a variety of wavelength dependences of optical absorptance by optimizing the dielectric multilayer.
In order to achieve the high detection efficiency in SSPDs, it is crucial to optimize the optical absorptance for a target wavelength. In the conventional SSPDs, a simple cavity structure consisting of dielectric resonant layers with a mirror layer has been used. This structure is relatively simple and can effectively achieve high absorptance at the target wavelength, and the wavelength dependencies of absorptance show a single peak structure. However, in this structure, it is difficult to realize the SSPDs with high efficiency over a carefully controlled spectral range, with rejection at other wavelengths to reduce the noises.
By adopting a new SSPD structure with dielectric multilayers, it became possible to design desired wavelength dependences of the optical absorptance. As materials of dielectric multilayer, silicon dioxide (SiO2) and titanium oxide (TiO2) were used, and the niobium nitride (NbN) superconducting nanowire was put on the dielectric multilayer. The wavelength dependences of the optical absorptance in the nanowire could be designed by optimizing the layer number and thicknesses of each layer in the dielectric multilayer. We developed the SSPDs based on the optimized design, and experimentally demonstrated that the wavelength dependences of the detection efficiency follow the calculated results well. Regarding the optical design method, in order to optimize the wavelength dependence of the absorptance effectively, we perform two-step simulation of the optical multilayer calculation and the finite element analysis.
In support of the SSPD measurements, the NICT team collaborated with Osaka University, Japan and the University of Glasgow, Scotland through the NICT internship scheme.
Future Prospects
The developed SSPD with the dielectric multilayer and the optical design method can be applied for wide wavelength region between ultraviolet and mid-infrared, and thus provides an important basis for development of application of SSPD to quantum cryptography, fluorescence spectroscopy, and remote sensing.
Suggested Items
Real Time with… IPC APEX EXPO 2024: Magnalytix's Services and Trends in the Electronics Industry
05/10/2024 | Real Time with...IPC APEX EXPOMike Bixenman, president of Magnalytix, explains Magnalytix's services, including third-party validation, test boards, electrical testing, and comprehensive reports. He also discusses emerging trends such as power electronics and reliability. Standards and design improvements also form part of this conversation.
Podcast Review: On the Line with… Designing for Reality
05/09/2024 | Duane Benson, Positive Edge LLCAs a technologist, if I were forced to come up with just one recurring theme that I might call a professional “nemesis,” it would be the difference between theory and reality. A lot of technology we have at our disposal works well in theory but falls short when reality hits. That’s not the only reason I chose to listen to and review On the Line with… Designing for Reality, featuring a series of conversations with ASC Sunstone’s Matt Stevenson, but it certainly helped that the title caught my eye.
EMA Webinar: Next Generation MCAD/ECAD for SOLIDWORKS
05/09/2024 | EMA Design AutomationLearn how the MCAD and ECAD experts at Hawk Ridge and EMA can help you solve your MCAD/ECAD integration challenges with this unique collaboration environment.
Sondrel Awarded New Video Processor ASIC Design and Supply Contract
05/09/2024 | SondrelSondrel, a leading provider of ultra-complex custom chips for leading global technology brands, is pleased to announce that it has won a major ASIC design and supply contract for a next generation, video processing chip.
Connect the Dots: Designing for Reality—The Pre-Manufacturing Process
05/08/2024 | Matt Stevenson -- Column: Connect the DotsI have been working with Nolan Johnson on a podcast series about designing PCBs for the reality of manufacturing. By sharing lessons learned over a long career in the PCB industry, we hope to shorten learning curves and help designers produce better boards with less hassle and rework. Episode 2 deals with the electronic pre-manufacturing process. Moving from CAD (computer-aided design) to CAM (computer-aided manufacturing) is a key step in PCB manufacturing. CAM turns digital designs into instructions that machines can use to actually build the PCB.