356 research outputs found
Maximizing the quality factor to mode volume ratio for ultra-small photonic crystal cavities
Small manufacturing-tolerant photonic crystal cavities are systematically
designed using topology optimization to enhance the ratio between quality
factor and mode volume, Q/V. For relaxed manufacturing tolerance, a cavity with
bow-tie shape is obtained which confines light beyond the diffraction limit
into a deep-subwavelength volume. Imposition of a small manufacturing tolerance
still results in efficient designs, however, with diffraction-limited
confinement. Inspired by numerical results, an elliptic ring grating cavity
concept is extracted via geometric fitting. Numerical evaluations demonstrate
that for small sizes, topology-optimized cavities enhance the Q/V-ratio by up
to two orders of magnitude relative to standard L1 cavities and more than one
order of magnitude relative to shape-optimized L1 cavities. An increase in
cavity size can enhance the Q/V-ratio by an increase of the Q-factor without
significant increase of V. Comparison between optimized and reference cavities
illustrates that significant reduction of V requires big topological changes in
the cavity
Influence of Pure Dephasing on Emission Spectra from Single Photon Sources
We investigate the light-matter interaction of a quantum dot with the
electromagnetic field in a lossy microcavity and calculate emission spectra for
non-zero detuning and dephasing. It is found that dephasing shifts the
intensity of the emission peaks for non-zero detuning. We investigate the
characteristics of this intensity shifting effect and offer it as an
explanation for the non-vanishing emission peaks at the cavity frequency found
in recent experimental work.Comment: Published version, minor change
Two-dimensional phase-space picture of the photonic crystal Fano laser
The recently realized photonic crystal Fano laser constitutes the first
demonstration of passive pulse generation in nanolasers [Nat. Photonics
, 81-84 (2017)]. We show that the laser operation is confined
to only two degrees-of-freedom after the initial transition stage. We show that
the original 5D dynamic model can be reduced to a 1D model in a narrow region
of the parameter space and it evolves into a 2D model after the exceptional
point, where the eigenvalues transition from being purely to a complex
conjugate pair. The 2D reduced model allows us to establish an effective band
structure for the eigenvalue problem of the stability matrix to explain the
laser dynamics. The reduced model is used to associate a previously unknown
origin of instability with a new unstable periodic orbit separating the stable
steady-state from the stable periodic orbit.Comment: 12 pages, 7 figures, journal, Phys. Rev. A, before editorial
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Highly efficient photonic nanowire single-photon sources for quantum information applications
Bone remodeling of the proximal tibia after uncemented total knee arthroplasty:secondary endpoints analyzed from a randomized trial comparing monoblock and modular tibia trays—2 year follow-up of 53 cases
High-Q AlAs/GaAs adiabatic micropillar cavities with submicron diameters for cQED experiments
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