Micro- and nano-cavity lasers for sensing applications | Posted on:2011-10-05 | Degree:Ph.D | Type:Dissertation | University:University of Illinois at Urbana-Champaign | Candidate:Giannopoulos, Antonios | Full Text:PDF | GTID:1468390011972382 | Subject:Engineering | Abstract/Summary: | | Lasers can be used for a multitude of sensing applications. This dissertation discusses two types of lasers for sensing applications. The use of an integrated vertical-cavity surface-emitting laser and photodetector as a position sensor is first detailed. Design, fabrication, and simulation of the position sensing capabilities are discussed. The use of a grating as the position gauge ultimately makes the range of measurement very large. Experimental demonstration of position sensing and velocity sensing is shown.;Photonic crystal membrane lasers, a type of nanoscale laser, are advantageous for sensing because of their compactness and ultra-small modal volume. Different aspects and properties of photonic crystal membrane lasers are discussed. The thermal characteristics of a photonic crystal laser are studied using a finite element method. Two new types of photonic crystal membrane cavity lasers are also presented and discussed: the decimated photonic crystal cavity and the heterostructure photonic crystal cavity. The later cavity is analyzed in greater detail via experiment and simulation.;Progress towards creating an electrically injected photonic crystal emitter is also discussed. The materials design and fabrication technique are presented. Here, the devices are fabricated in the InGaAs/GaAs material system. An oxidation layer is used to create a current aperture as well as to provide index contrast to the photonic crystal membrane. Calculations pertaining to the quality factor of the cavities in the diode configuration are presented. A fabrication sequence and required process development is discussed, as well as progress toward laser diode fabrication. | Keywords/Search Tags: | Laser, Sensing, Photonic crystal, Cavity, Discussed, Fabrication | | Related items |
| |
|