Nd-doped polymer waveguide amplifiers

Nd3+-complex-doped polymer channel waveguide amplifiers with various lengths and Nd3+ concentrations are fabricated by a simple procedure. Internal net gain at 840–950 nm and 1064 nm is experimentally and theoretically investigated under continuous-wave excitation at 800 nm. Internal net gain in the range 865–930 nm is observed and a peak gain of 2.8 dB at 873 nm is obtained in a 1.9-cm-long waveguide with a Nd3+ concentration of 0.6x10e20 cm-3 at a launched pump power of 25 mW. The small-signal gain measured in a 1-cm-long sample with a Nd3+ concentration of 1.03x10e20 cm-3 is 2.0 dB/cm and 5.7 dB/cm at 873 nm and 1064 nm, respectively. By use of a rate-equation model, the internal net gain at these two wavelengths is calculated and the macroscopic parameter of energy-transfer upconversion as a function of Nd3+ concentration is derived. Ease of fabrication, compatibility with other materials, and low cost make such rare-earth-ion-doped polymer waveguide amplifiers suitable for providing gain in many integrated optical devices

Improved arrayed-waveguide-grating layout avoiding systematic phase errors

We present a detailed description of an improved arrayed-waveguide-grating (AWG) layout for both, low and high diffraction orders. The novel layout presents identical bends across the entire array; in this way systematic phase errors arising from different bends that are inherent to conventional AWG designs are completely eliminated. In addition, for high-order AWGs our design results in more than 50% reduction of the occupied area on the wafer. We present an experimental characterization of a low-order device fabricated according to this geometry. The device has a resolution of 5.5 nm, low intrinsic losses (< 2 dB) in the wavelength region of interest for the application, and is polarization insensitive over a wide spectral range of 215 nm

Neodymium-complex-doped, photo-defined polymer channel waveguide ampliers

Channel waveguides based on a polymer, 6-fluorinated-dianhydride/epoxy, which is actively doped with a Nd complex, $Nd(thenoyltrifluoroacetone)_{3}$ 1,10-phenanthroline, are fabricated by a simple and reproducible procedure, spin coating a photodefinable cladding polymer onto a thermally oxidized silicon wafer, photopatterning, backfilling with the active core polymer, and spin coating with an upper cladding layer. Photoluminescence at 1060 nm from the $Nd^{3+}$ ions with a lifetime of 130 μs is observed. Optical gain at 1060 nm is demonstrated in channel waveguides with different $Nd^{3+}$ concentrations. By accounting for the waveguide loss of 0.1 dB/cm, an internal net gain of 8 dB is demonstrated for a 5.6-cm-long channel waveguide amplifier. Owing to the nature of the $Nd^{3+}$ complex, energy-transfer upconversion affects the gain only at $Nd^{3+}$ concentrations above $1 x 10^{20} cm^{-3}$

Demonstration of net gain at 1060nm in a Nd-complex-doped, photo-defined polymer channel waveguide

Optical amplification at 1060 nm was demonstrated in Nd(TTA)3phen-doped 6-FDA/epoxy channel waveguides, which indicates that a Nd-complex-doped polymer waveguide is well suited for optical amplification and potentially lasing.\u