Engineering light using large area photonic crystal devices

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2005.Includes bibliographical references.Photonic crystals are fabricated structures composed of a periodic arrangement of materials with differing indices of refraction. This research has focused on the realization of two distinct photonic crystal structures in which large area has played a key role: 1) large area broadband saturable Bragg reflectors, and 2) large area 2D photonic crystal devices. Saturable Bragg reflectors (SBRs) can be used to self-start ultra-short pulse generation in a variety of solid state and fiber lasers. To form shorter pulses, SBRs with broadband reflectivity and large area (100's of [mu]m) are required. This thesis describes the design and fabrication of large area broadband saturable Bragg reflectors through the monolithic integration of semiconductor saturable absorbers with large area broadband Bragg mirrors. One of the key elements for realizing this device is the development of a wet oxidation process to create buried low-index ... layers over large areas. Large area 2D photonic crystals enable new methods for routing and guiding light with applications in compact integrated optical circuits. This research has explored the design and fabrication of two large area (centimeter-scale) 2D photonic crystal devices: a superprism and a super- collimator.(cont.) A superprism is a photonic crystal device in which the direction of light propagation is extremely sensitive to the wavelength and angle of incidence. A super- collimator is a device in which light is guided by the dispersion properties of a photonic crystal slab without boundaries which define the light's path. Design, fabrication, and testing are discussed for both 2D photonic crystal devices.bu Sheila N. Tandon.Ph.D

Optically Induced Nanostructures

Nanostructuring of materials is a task at the heart of many modern disciplines in mechanical engineering, as well as optics, electronics, and the life sciences. This book includes an introduction to the relevant nonlinear optical processes associated with very short laser pulses for the generation of structures far below the classical optical diffraction limit of about 200 nanometers as well as coverage of state-of-the-art technical and biomedical applications. These applications include silicon and glass wafer processing, production of nanowires, laser transfection and cell reprogramming, optical cleaning, surface treatments of implants, nanowires, 3D nanoprinting, STED lithography, friction modification, and integrated optics. The book highlights also the use of modern femtosecond laser microscopes and nanoscopes as novel nanoprocessing tools