Sources and Detectors Group

The Sources and Detectors Group conducts research on the characterization of lasers, detectors, and related components. Principally through measurement services and innovation, the group provides the optoelectronics industry with traceability to national standards. Activities of the group are currently carried out in three project areas: Fiber Sources and Applications,  Laser Radiometry, and High Speed Measurements. 

Members of the Fiber Sources and Applications Project use frequency combs working at optical telecommunications wavelengths to develop measurement technology for a growing list of applications. Project physicists have transmitted signals from next-generation optical atomic clocks across hundreds of kilometers and have demonstrated how pairs of combs can increase by a factor of one hundred the speed of infrared spectroscopy for chemical analysis, while also enhancing sensitivity. Frequency combs also promise to provide extremely accurate distance measurements and to assess the quality of high-speed telecommunications signals with unprecedented precision.

Research in the Laser Radiometry Project is concerned with measuring laser, detector, and component properties such as laser power, laser beam profile, detector spectral responsivity, detector linearity and the attenuation of transmission components. To calibrate detectors and instruments used to measure the power or energy produced by a laser, the project has developed a family of standards that allow the accurate comparison of absorbed optical power to dissipated electrical power. Together, these standards permit calibrations at power levels from nanowatts to hundreds of kilowatts and energy levels from femtojoules to megajoules. Wavelength ranges include the visible through the near infrared, and selected wavelengths in the ultraviolet and mid infrared. For more information, see the Measurement Services section of this site. Instruments designed to receive power either in collimated beams or through optical fibers can be accommodated.

The High-Speed Measurements Project focuses on laser and detector temporal properties, such as detector and receiver frequency response and laser and optical amplifier noise. Project scientists calibrate photodiodes that can be used as electrical pulse generators. Electronics manufacturers use these NIST photodiodes to help tune oscilloscopes and other high-speed test equipment, which in turn tune commercial communications hardware. Project scientists are also developing metrology to characterize the quality of light signals pulsing through optical fiber, which will be vital to for future networks with all-optical switching equipment. The end result is better, faster, more robust hardware for current and next-generation fiber-optic networks.