S. Declair

Whispering gallery modes in zinc-blende AlN microdisks containing non-polar GaN quantum dots

Whispering gallery modes (WGMs) were observed in 60 nm thin cubic AlN microdisk resonators containing a single layer of non-polar cubic GaN quantum dots. Freestanding microdisks were patterned by means of electron beam lithography and a two step reactive ion etching process. Micro-photoluminescence spectroscopy investigations were performed for optical characterization. We analyzed the mode spacing for disk diameters ranging from 2-4 μm. Numerical investigations using three dimensional finite difference time domain calculations were in good agreement with the experimental data. Whispering gallery modes of the radial orders 1 and 2 were identified by means of simulated mode field distributions.

Photonic crystal waveguides intersection for resonant quantum dot optical spectroscopy detection

Using a finite-difference time-domain method, we theoretically investigate the optical spectra of crossing perpendicular photonic crystal waveguides with quantum dots embedded in the central rod. The waveguides are designed so that the light mainly propagates along one direction and the cross talk is greatly reduced in the transverse direction. It is shown that when a quantum dot (QD) is resonant with the cavity, strong coupling can be observed via both the transmission and crosstalk spectrum. If the cavity is far off-resonant from the QD, both the cavity mode and the QD signal can be detected in the transverse direction since the laser field is greatly suppressed in this direction. This structure could have strong implications for resonant excitation and in-plane detection of QD optical spectroscopy.

Simulation of Mutual Coupling of Photonic Crystal Cavity Modes and Semiconductor Quantum Dots

We present numerical results of the mutual coupling between photonic crystal cavities and semiconductor quantum dots. Normal mode splitting between a single cavity mode and a single quantum dot is shown under weak excitation, while under strong excitation Q‐factor dependent side bands appear, according to the AC‐Stark effect. Coupled photonic crystals, aligned parallel but displaced under a 30°‐angle for efficient coupling, show line splittings of all eigenmodes, if a single eigenmode is resonantly coupled to a single quantum dot. The mutual coupling of N resonant quantum dots to a single cavity mode results in a N scaling of the splitting, known from quantum optics, but corrected by the field amplitude fraction for not collocated quantum dots.

Numerical Analysis of Coupled Photonic Crystal Cavities

We present an analysis of the coupling between photonic crystal cavities in different geometries. Inline‐, side‐ and angle‐coupled L3‐geometries are investigated numerically in three dimensions. Asymmetric mode splitting of the fundamental mode for the L3‐cavity is shown for all geometrical setups evidencing for strong cavity‐cavity interactions. The coupling efficiency for the fundamental mode is shown to be best for a 30° angle between the cavity‐centers due to the direction of in‐plane leackage out of the cavites.

Anticrossing of Whispering Gallery Modes in Microdisk Resonators Embedded in a Liquid Crystal

We numerically investigate Whispering Gallery Modes (WGM) in a subwavelength microdisk resonator [1] embedded in an uniaxial anisotropic liquid crystal environment. It is shown that the WGMs have anticrossing behavior when modes of different radial mode order M or azimuthal order N approach each other spectrally.