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Physical Measurement Laboratory / Applied Physics Division

Sources and Detectors Group

Projects/Programs

Displaying 1 - 12 of 12
bolometer

Earth Energy Budget

Ongoing
The Earth Energy Balance is a fundamental climate measurement that has been monitored from space for over 40 years. Microfabricated, absolutely calibrated bolometers with vertically-aligned carbon nanotubes that are developed by this project provide a more accurate and more compact method for
High Amplification Laser-pressure Optic

High Amplification Laser-pressure Optic (HALO)

Ongoing
We have assembled a high-accuracy laser power meter based on radiation pressure with multiple reflections of the laser on the sensing mirror. A custom electrostatic force balance supports a high-reflectivity sensing mirror upon which a high-power continuous wave laser beam is incident at ~ 45
x-ray laser welding setup

High-Power Laser Applications

Ongoing
Measurement challenges Traditional measurements of laser power or energy involve absorbing the laser light and measuring the resulting temperature increase of the absorber. However, as the power and total energy delivered by these lasers increases, thermal management, absorber size, and response
Laser Power and Energy Meter Calibration team

Laser Power and Energy Meter Calibration

Ongoing
For calibrating instruments used to measure the power or energy emitted by a laser, or single photon source specially designed primary and secondary standards consisting of calorimeters, pyroelectric detectors, thermal radiometers, photodiode traps and recently superconducting nanowire single-photon
summary plot

Metal Additive Manufacturing Laser Power Assessment

Ongoing
A calibrated (U=1.2 %, k=2) power meter was taken to a variety of AM locations (industry, academic, government, DoD) to anonymously assess the accuracy with which these institutions know the laser power being delivered to the workpiece. At each site, the LPBF operator was asked to use the AM system
beam box

The Photoforce Project

Ongoing
Traditional power meters measure the power of a laser beam by absorbing its energy. Radiation pressure (photon momentum) permits the measurement of a beam’s power by “absorbing” its momentum and reflecting its energy. Light reflecting from a mirror causes a force that is proportional to its optical
Planar absolute cryogenic radiometer with multiwall vertically-aligned carbon nanotubes. Superconducting transition-edge sensor. Fully-lithographic fabrication.

Photonic Radiometry

Ongoing
Meeting the needs of the photonics industry and anticipating emerging technologies requires investigation and development of improved measurement methods and instrumentation. This project develops state-of-art, absolute microfabricated thermal detectors with absorber coatings consisting of carbon
equipment

Quantum Radiometry

Ongoing
For quantum applications, it is important to generate quantum states of light and detect them with extremely high efficiency. This project explores the metrology challenges associated with precision measurement of single photon sources and detectors. The classical photonic radiometry techniques used
Passive millimeter-wave image of concealed contraband (handgun and ceramic knife).

Terahertz Imaging and Sources

Ongoing
Over the past several years, we have focused on bolometric detection of THz radiation. Our initial work on cryogenic detectors has been extended to antenna-coupled bolometers operating at room temperature. These detectors provide a rugged, low-cost alternative for homeland security applications; e.g

Training and optimization of hardware neural networks

Ongoing
The goal of this project is to develop a general method that can train many different types of neural networks, and to demonstrate and evaluate their performance on new emerging hardware. We aim to develop and demonstrate training on diverse hardware platforms, and in the presence of realistic noise