1,955 research outputs found
Transmission of Slow Light through Photonic Crystal Waveguide Bends
The spectral dependence of a bending loss of cascaded 60-degree bends in
photonic crystal (PhC) waveguides is explored in a slab-type
silicon-on-insulator system. Ultra-low bending loss of (0.05+/-0.03)dB/bend is
measured at wavelengths corresponding to the nearly dispersionless transmission
regime. In contrast, the PhC bend is found to become completely opaque for
wavelengths range corresponding to the slow light regime. A general strategy is
presented and experimentally verified to optimize the bend design for improved
slow light transmission.Comment: 4 pages, 3 figures; submitted to Optics Letter
Mapping the optical properties of slab-type two-dimensional photonic crystal waveguides
We report on systematic experimental mapping of the transmission properties
of two-dimensional silicon-on-insulator photonic crystal waveguides for a broad
range of hole radii, slab thicknesses and waveguide lengths for both TE and TM
polarizations. Detailed analysis of numerous spectral features allows a direct
comparison of experimental data with 3D plane wave and finite-difference
time-domain calculations. We find, counter-intuitively, that the bandwidth for
low-loss propagation completely vanishes for structural parameters where the
photonic band gap is maximized. Our results demonstrate that, in order to
maximize the bandwidth of low-loss waveguiding, the hole radius must be
significantly reduced. While the photonic band gap considerably narrows, the
bandwidth of low-loss propagation in PhC waveguides is increased up to 125nm
with losses as low as 82dB/cm.Comment: 10 pages, 8 figure
Mid-infrared broadband modulation instability and 50 dB Raman assisted parametric gain in silicon photonic wires
Abstract: We demonstrate broadband modulation instability, > 40 dB parametric amplification with on-chip gain bandwidth > 580 nm, and narrowband Raman-assisted peak on-chip gain exceeding 50 dB, using mid-infrared dispersion-engineered silicon nanophotonic wires
Deterministic tuning of slow-light in photonic-crystal waveguides through the C and L bands by atomic layer deposition
We demonstrate digital tuning of the slow-light regime in silicon
photonic-crystal waveguides by performing atomic layer deposition of hafnium
oxide. The high group-index regime was deterministically controlled (red-shift
of 140 +/- 10 pm per atomic layer) without affecting the group-velocity
dispersion and third-order dispersion. Additionally, differential tuning of 110
+/- 30 pm per monolayer of the slow-light TE-like and TM-like modes was
observed. This passive post-fabrication process has potential applications
including the tuning of chip-scale optical interconnects, as well as Raman and
parametric amplification.Comment: 14 pages, 5 figure
- …