This paper reviews the development of cerebral scintigraphy from its early days of planar imaging with simple technetium-99m labelled compounds to the recent revival of the technique in the form of positron-emission and single-photon emission tomography. A short explanation of instrumentation and radiopharmaceuticals is given as a prelude to a description of both techniques in normal and pathol...

We predict a bistability in the photon emission from a solid-state single-atom laser comprising a microwave cavity coupled to a voltage-biased double quantum dot. To demonstrate that the single-atom laser is bistable, we evaluate the photon emission statistics and show that the distribution takes the shape of a tilted ellipse. The switching rates of the bistability can be extracted from the ele...

For gamma-ray bursts (GRBs) born in a stellar wind, as the reverse shock crosses the ejecta, usually the shocked regions are still precipitated by the prompt MeV γ−ray emission. Because of the tight overlapping of the MeV photon flow with the shocked regions, the optical depth for the GeV photons produced in the shocks is very large. These high energy photons are absorbed by the MeV photon flow...

We present an exactly solvable model for photon emission, which allows us to examine the evolution of the photon wave function in space and time. We apply this model to coherent phenomena in three level sytems with special emphasis on the effects of the photon detection process.

In this paper, we present a high quality single-photon source based on the two-level system undergoing rapid adiabatic passage (RAP). A trigger strategy (sweet region) is suggested to optimize the single-photon emission and explain a counter-intuitive phenomenon on the optimal parameters. The RAP strategy of single-photon source is robust against control error and environmental fluctuation.

We explore the characteristics of a source of anti-bunched microwave photons. This source has been developed by Max Hofheinz’s and its stationary properties have been characterized. In order to fully characterize this source when operated with pulse excitation, we modify the experimental setup and develop new numerical tools to extract the time resoled first and second order photon correlation ...

Pre-breakdown (leakage) and breakdown currents and photon-emission associated with the currents, under impulse (0.36!10 IJ-S) voltage stress, along high purity (p>30 KQ em) silicon, with and without gold end contacts in vacuum (-lQ-6 Torr), are discussed. Three distinct phases leading to the breakdown condition are observed. These are one-carrier (hole) leakage current, two-carrier (electrons a...

We consider theoretically nonlinear effects in a semiconductor quantum well embedded inside a photonic microcavity. Two-photon absorption by a 2p exciton state is considered and investigated; the matrix element of two-photon absorption is calculated. We compute the emission spectrum of the sample and demonstrate that under coherent pumping the nonlinearity of the two photon absorption process g...

introduction 3d reconstruction of an object from its 2d cross-sections (slices) has many applications in different fields of sciences such as medical physics and biomedical engineering. in order to perform 3d reconstruction, at first, desired boundaries at each slice are detected and then using a correspondence between points of successive slices surface of desired object is reconstructed. mate...

We report a facile strategy to synthesize folic acid-functionalized two-photon absorbing (TPA) nanoparticles with aggregation-induced emission for targeted cancer cell imaging using a two-photon fluorescence microscope.