introduction the potential hazards posed by exposure to radiation from radon have been of great concern worldwide, since it is especially associated with increased risk of lung cancer. some radioisotopes of radon progeny deposited in the human lungs emit β particles followed by the γ rays. while γ rays are comparatively less damaging to the respiratory system than α and β particles, it is the p...

introduction evaluation of the delivered dose of externally wedged photon beams by external diode dosimeters during the treatment process requires the estimation of exit surface dose correction factors in various wedge angles and field sizes. materials and methods a system of absorbed dose evaluation, using p-type diode dosimeters placed on the exit surface of a phantom, was characterized for e...

Temporal modulation of the quantum vacuum through fast motion a neutral body or changes its optical properties is known to promote virtual into real photons, so-called dynamical Casimir effect. Empowering protocols with spatial control could enable shaping spectral, spatial, spin, and entanglement emitted photon pairs. Space–time metasurfaces have been proposed as platform realize this physics ...

The advent of photon-based quantum cryptography, communication and computation schemes is increasing the need for light sources that produce individual photons; as unwanted additional photons can render quantum cryptographic links insecure and degrade quantum-computation efficiencies. More specifically, it would be useful to have these photons created in response to an external trigger, or even...