EPFL

Bose-Einstein condensation of microcavity polaritons

Sarchi, Davide ; Savona, Vincenzo (Dir.)

Thèse sciences Ecole polytechnique fédérale de Lausanne EPFL : 2007 ; no 3906.

Université de Neuchâtel

Design, fabrication, and testing of intersubband infrared photodetectors operating at wavelengths between 2 ųm and 17 ųm

Giorgetta, Fabrizio ; Hofstetter, Daniel (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2007 ; Th.1982.

Intersubband (ISB) photon detectors based on photon – electron interactions between quantized electron subbands in the conduction band of semiconductor heterostructures are presented. As opposed to interband devices, the operating wavelength of ISB devices is set by choosing appropriate layer thicknesses of the heterostructure and is not fixed by the semiconductor material system. As only...

Université de Neuchâtel

Optical pumping : a possible approach towards a SiGe Quantum Cascade Laser

Scheinert, Maxi ; Faist, Jérôme (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2007 ; Th.1979.

Since the first Quantum Cascade Laser (QCL) was realized in 1994 in the AlInAs/InGaAs material system, it has attracted a wide interest as infrared light source. Main applications can be found in spectroscopy for gas-sensing, in the data transmission and telecommunication as free space optical data link as well as for infrared monitoring. This type of light source differs in fundamental ways from...

Université de Neuchâtel

Near infrared intersubband absorption and photovoltaic detection in GaN/AIN multi quantum well structures

Baumann, Esther ; Hofstetter, Daniel (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2007 ; Th.1956.

Due to the large conduction band offset of nearly 2 eV between GaN and AlN, group III nitride semiconductor heterostructures are of great interest for optoelectronics based on intersubband transitions (ISBTs). These properties allow the extension of the ISBT wavelength range into the near infrared. In this work near infrared ISBTs in GaN/AlN heterostructures were investigated for samples grown by...

Université de Neuchâtel

Quantum cascade lasers at terahertz frequencies

Ajili, Lassaad ; Faist, Jérôme (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2007 ; 1941.

The thesis which I have pleasure to present you is the fruit of the research work during four years in the laboratory of mesoscopic physic located at the institute of physics of Neuchâtel. The extraordinary progress realized at the end of the seventy years, in the control of the growth, atomic layer by atomic layer, of semiconductor heterostructures have developed a true quantum engineering of...

Université de Neuchâtel

Broadly tunable mid-infrared quantum cascade lasers for spectroscopic applications

Maulini, Richard ; Faist, Jérôme (Dir.)

Thèse de doctorat : Université de Neuchâtel, 2006 ; 1895.

Quantum cascade lasers are unipolar semiconductor lasers based on intersubband transitions in heterostructures. These lasers, which have demonstrated continuous wave operation at room temperature in the mid-infrared spectral range, are well suited for the realization of compact, ultra-sensitive, trace-gas sensors based on absorption spectroscopy. Up to now, only distributed feedback (DFB)...