Quantum Sensors Program (QSP)
Program Manager: Dr. Peter Haaland
The Quantum Sensors Program (QSP) is applying phenomenology from quantum mechanics to improve the performance of military sensors that use electromagnetic radiation.
The resolution of a classical sensor is limited by the wavelength, l, of radiation that is sensed. This limit is inversely proportional to l, so that shorter wavelength radiation achieves higher resolution. In other words, the classical resolution of green laser radar operating at l = 532 nanometers is about twice that of a night vision goggle operating at l =1 micron and 20 times that of a forward looking infrared camera operating at l =10.6 microns. According to classical physics this relationship between wavelength and resolution is unbreakable.
Scattering and absorption of radiation by the atmosphere also limit the range of wavelengths that can be used to sense the environment. For example, light whose wavelength is shorter than 280 nm is strongly absorbed by oxygen, and wavelengths around 2 microns are absorbed by water vapor. The combined effects of propagation losses and the classical limit constrain the practical resolution of classical military sensors.
In quantum mechanics, higher resolution is attributed to higher energy per quantum state. This reduces to the classical limit when the state has only one photon. However, in a purely quantum mechanical phenomenon called entanglement, multiple photons can jointly constitute a single quantum state, so that resolution is now a multiple of the classical limit. For example, laboratory experiments have shown that two entangled red photons yield the same resolution as a single blue photon. This decoupling of optical wavelength and optical resolution would provide a basis for new, high resolution sensor concepts based on laser radars, FLIR cameras, night vision equipment, and microwave platforms.
Phase I of the Quantum Sensors Program investigates several quantum sensor approaches to determine whether the resolution improvement through entanglement is robust to outdoor propagation and interaction with targets. In the “Type I” approach sensors transmit entangled photons to the target whereas “Type II” sensors constrain the entangled state to the detector. A third approach, based on ghost imaging, is also being explored. If any of these approaches is robust, Phase II of the program will define component technology requirements for development of quantum sensors during Phase III.
Register on the QSP web site to ensure you receive information on future meetings and solicitations: https://dtsn.darpa.mil/qsp/
