Photon Manipulation Applications In Semiconductor Lasers Based On Surface Plasmons

Surface plasmons can localize photons along the metal surface, which makesmanipulating light in subwavelength scale or even nanoscale possible. Surfaceplasmons find their applications in the fields of bio-sensing, chemical sensing,nano-optical lithography, data storage, optical chips interconnection, solar cells, andoptical beaming. This thesis mainly research on manipulating photons insemiconductor lasers using surface plasmons, concerning optical mode selection,plasmonic lasering, and divergence angle optimizing. The main research result andcontent of the thesis contains:1. The coupling conditions for surface plasmons in a metal grating. Thecoupling condition for a500nm duration Au-SiO2grating is discussed. When thefilling factor reaches95%, the wavelength766nm photon coupling efficiency fromphotons to surface plasmons reaches over94%. This wavelength is the mainlyworking wavelength for the absorption of solar cells, which makes theoptical-voltage materials more efficient in absorbing photons.2. The unsymmetrical transmission phenomenon in a metal grating isdiscovered. This phenomenon is basically caused by different coupling conditionbetween surface plasmon and photons when incident light travels forward and backward. An obvious unsymmetrical transmission phenomenon between555nmand766nm in the specific500nm duration Au-SiO2grating has been observed.Especially between wavelength565nm and589nm at a filling factor of0.7, thephotons are allowed to transmit from only forward direction. The backwardtransmission is blocked. This phenomenon disobeys the transmission theorem ofoptical films, which makes the single side transmission mirror and optical logicalcircuit possible.3. A940nm semiconductor laser with top coupling metal grating is madeexperimentally. The grating serves as mode selecting mechanism. Surface plasmonblocks the TM mode. Thus the lasering spectrum has been narrowed to0.07nm. Thelasering divergent angle for fast axis is reduced from36°to17.6°, as well as thedivergent angle for slow axis is reduced from7.3°to2.7°.4. A surface plasmon laser source is designed. This laser source is based onmonoside Bragg reflection waveguide and Otto configuration. It supplies808nmhigh power plasmonic laser source in the near field meanwhile works in roomtemperature electrical pumping condition. The lasering power may reach overmilliwatt, comparing to nanowatt for other surface plasmon laser sources.5. A facet structure based on dual metal gratings used for808nm Braggreflection waveguide is designed. The double lasering farfield lobes, each22.2°indivergient angle has been optimized to a single lasering farfield lobe with only6.1°farfield divergient angle. Both enhanced transmission and optical beaming usingsurface plasmons are concerned.