@inproceedings{22ff3de0b7784da1975967f46003a176,
title = "Erbium-doped spiral amplifiers with 20 dB gain on a silicon chip",
abstract = "We report the fabrication and optical characterization of long, spiral-shaped erbium-doped aluminum oxide (Al2O3:Er3+) channel waveguides for achieving high overall signal amplification on a small footprint. Al2O3:Er3+ films with Er3+ concentrations in the range between 0.443.1×10^20 cm^-3 were deposited by reactive co-sputtering onto standard, thermally oxidized silicon substrates. Spiral-shaped waveguides were designed and structured into the films by chlorine-based reactive ion etching. In the current design, each spiral waveguide occupies an area of 1 cm^2. Typical background propagation losses near 1500 nm are (0.2±0.1) dB/cm. A commercially available, pigtailed diode laser at 976 nm was employed as the pump source. The erbium-doped waveguide amplifiers were characterized in the small-signal-gain regime at the peak-gain wavelength (λ = 1532 nm) of Al2O3:Er3+. A maximum of 20 dB of internal net gain was measured for a 24.5-cm-long spiral waveguide with an Er3+ concentration of 0.95×10^20 cm^-3. Similar results were obtained for a shorter spiral with an Er3+ concentration about twice as high. Samples with lower concentration exhibited lower gain because of insufficient pump absorption, while samples with higher concentration showed less gain because of migration-accelerated energy transfer up-conversion and, more importantly, a fast quenching process.",
keywords = "EWI-24710, IR-90655, METIS-304093, IOMS-APD: Active Photonic Devices",
author = "V{\'a}zquez-C{\'o}rdova, {Sergio Andr{\'e}s} and Edward Bernhardi and Kerstin Worhoff and {Garc{\'i}a Blanco}, {Sonia Maria} and Markus Pollnau",
note = "eemcs-eprint-24710 - Paper 913308 ",
year = "2014",
month = may,
doi = "10.1117/12.2052298",
language = "English",
isbn = "978-1-62841-081-5",
series = "Proceedings of the SPIE",
publisher = "SPIE",
number = "913308",
pages = "Paper 913308",
editor = "Laurent Vivien and Seppo Honkanen and Lorenzo Pavesi and Stefano Pelli and Shin, {Jung Hun}",
booktitle = "Photonics Europe",
address = "United States",
}