Jan Hampe

Electro-optic modulation in slotted resonant photonic crystal heterostructures

Two dimensional photonic crystal waveguides in high index materials enable integrated optical devices with an extremely small geometrical footprint on the scale of micrometers. Slotted waveguides are based on the guiding of light in low refractive index materials and a field enhancement in this particular region of the device. In this letter we experimentally demonstrate electro-optic modulation in slotted photonic crystal waveguides based on silicon-on-insulator substrates covered and infiltrated with nonlinear optical polymers. A photonic crystal heterostructure is used to create a cavity, while simultaneously serving as an electrical connection from the slot to the metal electrodes that carry the modulation signal.

40 GHz electro-optic modulation in hybrid silicon–organic slotted photonic crystal waveguides

In this Letter we demonstrate broadband electro-optic modulation with frequencies of up to 40 GHz in slotted photonic crystal waveguides based on silicon-on-insulator substrates covered and infiltrated with a nonlinear optical polymer. Two-dimensional photonic crystal waveguides in silicon enable integrated optical devices with an extremely small geometric footprint on the scale of micrometers. The slotted waveguide design optimizes the overlap of the optical and electric fields in the second-order nonlinear optical medium and, hence, the interaction of the optical and electric waves.

Resonance splitting in gyrotropic ring resonators

We present the theoretical concept of an optical isolator based on resonance splitting in a silicon ring resonator covered with a magneto-optical polymer cladding. For this task, a perturbation method is derived for the modes in the cylindrical coordinate system. A polymer magneto-optical cladding causing a 0.01 amplitude of the off-diagonal element of the dielectric tensor is assumed. It is shown that the derived resonance splitting of the clockwise and counterclockwise modes increases for smaller ring radii. For the ring with a radius of approximately 1.5μm, a 29GHz splitting is demonstrated. An integrated optical isolator with a 10μm geometrical footprint is proposed based on a critically coupled ring resonator.

Nonreciprocal silicon waveguides and ring resonators with gyrotropic cladding

Concepts are demonstrated for nonreciprocal Mach-Zehnder interferometers (MZIs) and ring resonators with polymer gyrotropic cladding. The isolation with −20 dB suppression is theoretically demonstrated in a 2µm radius ring resonator.

Hybrid silicon-organic racetrack resonator designs for electro-optical modulation

Racetrack resonators based on the silicon-on-insulator platform are proposed for electro-optical modulation. The resonators are functionalized by a cladding of a second order nonlinear optical polymer. Two different concepts for the racetrack design employing different waveguide geometries for quasi-TE and quasi-TM polarization operation are presented. In both resonator designs the electrical contact is established by fully etched segmented electrode sections to allow for an easy fabrication process. For quasi-TM polarization the width of the strip waveguide is optimized to 400 nm. The Q factor of 2000 is measured for a sample with segmented electrode. A loss of 0.4 dB per segmented waveguide is deducted. For the quasi-TE polarization the slot waveguide geometry is optimized to 470 nm total width including a vertical slot of 90 nm width. Only the straight parts of the racetrack are slotted, while the bends are built from strip waveguides. To convert the mode from strip to slot geometry stub like couplers of 100 nm length are employed. The measured Q factor is 550. The in device Pockels coefficient is measured to r33 = 1 pm/V. This small value indicates a very low poling induced polar order which needs to be improved. This is a topic of current investigation.

Integrated Non Reciprocal Ring Resonators

We present the theoretical concept of an optical isolator based on a resonance splitting in a silicon ring resonators covered by a magneto-optical polymer cladding. A polymer magneto optical cladding causing a 0.01 amplitude of the off-diagonal element of the dielectric tensor is assumed. Using a perturbation method it is shown that the resonance splitting of the clockwise and counter-clockwise modes increases for smaller ring radii. For the ring with a radius of approximately 1.5μm a 29GHz splitting is demonstrated. An optical isolator is proposed based on a critically coupled ring resonator.

High speed electro-optic modulation in hybrid silicon on insulator slotted photonic crystal

We demonstrate GHz electro-optic modulation in a slotted silicon photonic crystal infiltrated with nonlinear optical polymer material.

Multi GHz modulation in ultra compact organic-inorganic structures

In this letter we demonstrate broadband electro-optic modulation with frequencies up to 40 GHz in slotted photonic crystal waveguides based on silicon-on-insulator substrates covered and infiltrated with a nonlinear optical polymer. Two dimensional photonic crystal waveguides in silicon enable integrated optical devices with an extremely small geometrical footprint on the scale of micrometers. The slotted waveguide design optimizes the overlap of the optical and electric field in the second order nonlinear optical medium and hence the interaction of the optical and electric wave.

Electro-optic modulation in hybrid SOI and polymer slotted resonant photonic crystal heterostructures

We present experimental evidence of electro-optic modulation in slotted photonic crystal heterostructure waveguides based on silicon-on-insulator substrates covered and infiltrated with nonlinear optical polymer material.

Disorder limits in passive and amplifying slow light waveguides

We present a simulation approach to estimate the effect of disorder induced backscattering in slow light photonic crystal line-defect waveguides. The backscattering leads to localization and thus limits the maximal length of such waveguides. Loss in passive waveguides in the localization regime reduces ripples in spectral transmission and group delay whereas gain increases these resonant multiple scattering effects.