Sharif Digital Repository

Detectors play an important role in almost all scientific experiments and the results of the experiment highly depend on the performance of the applied detector (e.g. the detector detectivity, noise, detection threshold, time constant, …). In general a detector is defined as a device which transforms a quantity (e.g. pressure, energy, photon, …) to another one(e.g. mechanical displacement, electrical current, voltage, …). High temperature superconductor transition edge bolometers (TEB) are one of the most promising devices that due to the wavelength independent nature of their optical response can be used to detect the electromagnetic radiation over the whole spectrum from x-ray to the far... 

Conventionally all objects radiate most of its energy in the from of infrared waves, therefore, infrared photodetectors for detecting objects is important and more study is done on improve the detecting parameters. The proposed structures are developed from bulk to quantum well and quantum dots in recently years. In this work at reason insensitivity to incident light polarization, flexible operation wavelength, high operation temperature, inherent photovoltaic effect, low capture probability we study the structure of quantum dot infrared photodetectors and then for improve the detecting parameters structure of two layers quantum dot separated with a layer thin barrier (bilayer). And then a...