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Mid-infrared quantum dot emitters utilizing planar photonic crystal technology

Shaner, Eric A.; Passmore, Brandon S.; Lyo, S.K.; Cederberg, Jeffrey G.; Subramania, Ganapathi S.; El-Kady, I.

The three-dimensional confinement inherent in InAs self-assembled quantum dots (SAQDs) yields vastly different optical properties compared to one-dimensionally confined quantum well systems. Intersubband transitions in quantum dots can emit light normal to the growth surface, whereas transitions in quantum wells emit only parallel to the surface. This is a key difference that can be exploited to create a variety of quantum dot devices that have no quantum well analog. Two significant problems limit the utilization of the beneficial features of SAQDs as mid-infrared emitters. One is the lack of understanding concerning how to electrically inject carriers into electronic states that allow optical transitions to occur efficiently. Engineering of an injector stage leading into the dot can provide current injection into an upper dot state; however, to increase the likelihood of an optical transition, the lower dot states must be emptied faster than upper states are occupied. The second issue is that SAQDs have significant inhomogeneous broadening due to the random size distribution. While this may not be a problem in the long term, this issue can be circumvented by using planar photonic crystal or plasmonic approaches to provide wavelength selectivity or other useful functionality.

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TYPE SAND Report YEAR 2008
DOIOSTI

Investigation of 2D laterally dispersive photonic crystal structures : LDRD 33602 final report

Vawter, Gregory A.; Peters, D.W.; Wendt, J.R.; Hadley, G.R.; Peake, Gregory M.; Guo, Junpeng; Subramania, Ganapathi S.

Artificially structured photonic lattice materials are commonly investigated for their unique ability to block and guide light. However, an exciting aspect of photonic lattices which has received relatively little attention is the extremely high refractive index dispersion within the range of frequencies capable of propagating within the photonic lattice material. In fact, it has been proposed that a negative refractive index may be realized with the correct photonic lattice configuration. This report summarizes our investigation, both numerically and experimentally, into the design and performance of such photonic lattice materials intended to optimize the dispersion of refractive index in order to realize new classes of photonic devices.

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TYPE Report YEAR 2003
DOIOSTI

Turning the microcavity resonant wavelength in a 2D photonic crystal by modifying the cavity geometry

Proposed for publication in Applied Physics Letters.

Subramania, Ganapathi S.; Lin, Shung W.; Wendt, J.R.; Rivera, Jonathan M.

High-quality-factor microcavities in two-dimensional photonic crystals at optical frequencies have a number of technological applications, such as cavity quantum electrodynamics, optical switching, filtering, and wavelength multiplexing. For such applications, it is useful to have a simple approach to tune the microcavity resonant wavelength. In this letter, we propose a microcavity design by which we can tune the resonant wavelength by changing the cavity geometry while still obtaining a high quality factor.

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TYPE Journal Article YEAR 2003
DOIOSTI
Results 101–122 of 122
Results 101–122 of 122