Sökning: "Infrared devices"
Visar resultat 1 - 5 av 104 avhandlingar innehållade orden Infrared devices.
1. Mid-infrared photonic devices for on-chip optical gas sensing
Sammanfattning : Gas detection is crucial in a wide range of fields and applications, such as safety and process control in the industry, atmospheric sciences, and breath diagnostics. Optical gas sensing offers some key advantages, compared to other sensing methods such as electrochemical and semiconductor sensing: high specificity, fast response, and minimal drift. LÄS MER
2. Spectral Management in Quasi-Phase-Matched Parametric Devices
Sammanfattning : Nonlinear optical interaction in quasi-phase-matched structures opens up unique possibilities to build compact and efficient parametric devices such as optical parametric oscillators, generators, and amplifiers with tailored spectral properties. The focus of this thesis is on novel parametric interactions with periodically-poled KTiOPO4 (PPKTP) as the parametric gain medium. LÄS MER
3. Optical modelling of conjugated polymers : from materials to devices
Sammanfattning : Measurements and modelling of theoretical properties of polymer-based photovoltaic devices, PPVDs, are the subjects of this thesis. Modelling refers both to modelling of materials, based on extraction of the dielectric function, and to modelling of devices by computer simulation of the optical electrical field inside PPVDs. LÄS MER
4. Novel Materials and Technologies for IR Optoelectronic Applications
Sammanfattning : This thesis focuses on novel III-V materials (InAs/GaSb type-II superlattices, T2SL, and dilute bismides) and metamorphic growth techniques for infrared optoelectronics all of which may find wide spread applications in telecommunication, energy harvesting and saving, sensing and imaging. Mid-wavelength infrared (MWIR) and long-wavelength infrared (LWIR) photodetectors at the atmospheric windows of 3-5 and 8-12 µm, respectively, are currently dominated by HgCdTe and quantum well infrared photodetectors. LÄS MER
5. Type-II interband quantum dot photodetectors
Sammanfattning : Photon detectors based on single-crystalline materials are of great interest for high performance imaging applications due to their low noise and fast response. The major detector materials for sensing in the long-wavelength infrared (LWIR) band (8-14 µm) are currently HgCdTe (MCT) and AlGaAs/GaAs quantum wells (QW) used in intraband-based quantum-well infrared photodetectors (QWIPs). LÄS MER