Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503226
Title: Spectral properties and modes of surface microcavities
Author: Pennington, R. C.
Awarding Body: University of Southampton
Current Institution: University of Southampton
Date of Award: 2009
Availability of Full Text:
Access from EThOS:
Access from Institution:
Abstract:
This thesis describes the experimental investigations into the transverse mode structure of nearly hemispherical microcavities. The nearly hemispherical niicrocavity structures are fabricated electrocemically through a template of self assembled latex spheres. Controlling the electrochemical parameters, such as the electrochemical solution and electrode potential. allows a wide range of uearly henuspherical rnicrocavities to be realised. The spatial intensity profiles arid resonant frequeucies of the transverse modes of nearly hemispherical nucrocavities are measured experimentally for a wide range of cavity lengths amid mirror curvatures. The experimental mode profiles are radially symmetric Gauss-Laguerre modes, but do not display the frequency degeneracies typical of large scale optical cavities. The nearly hemispherical mnicrocavity samples are compared to investigate how the cavity parameters. such as cavity length and mirror curvature, affect the experimental spatial intensity profiles and resonant frequencies of the transverse modes. Higher order modes are observed despite the fact that they are forbidden due to the symmetrical coupling geometry. rrhe symmetry breaking is shown to be produced by the surface roughness of the curved nnrror. The frequency degeneracy lifting which occurs in the nearly hemispherical niicrocavity structures can he explained and modelled by considering non-parabolic elements in the cavity. A nmnher of mathematical models for the cavity propagation are developed based on paraxial theory. rrliese models are analysed and the predictions made from the models are compared with the experimental profiles and frequencies. The basic agreement between theory and experinient shows that the paraxial theory is able to model the cavity modes. However, the spectrum and the mnode profiles are cpnte sensitive functions of the geometry of the cavity amid the surface roughness of the cavity mirrors. The nearly hemispherical mnicrocavities are structures which offer a new fabrication technique allowing inexpensive and a ummconmplicated method of fabrication. An important feature of the nearly hemispherical microcavities is the tunablity, and the ease in which this can be achieved. The structures are also empty, and this will allow them, in the future, to be easily filled with functional optical nmaterials such as liquid crystals.
Supervisor: Kaczmarek, Malgosia ; Baumberg, Jeremy Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.503226  DOI: Not available
Keywords: TP Chemical technology ; TK Electrical engineering. Electronics Nuclear engineering ; QC Physics
Share: