December 12, 2005 Ipswich, UK -- The Centre for Integrated Photonics (CIP) announced that it has developed a reflective semiconductor optical amplifier offering highly optimized performance for WDM passive optical network (PON) applications. Capable of delivering 20 dB of gain, CIP says the semiconductor optical amplifier (SOA) can be modulated at rates up to 1.5 Gbits/sec to provide wavelength-agile optical data transmission facilities for clients in FTTH/FTTP access network architectures, without the expense of a tunable wavelength source.
According to CIP, a novel curved waveguide architecture inside the monolithic InP (indium phosphide) based SOA, the SOA-RL-OEC-1550, delivers smooth output characteristics with a ripple of just 0.5 dB typical and a polarization-dependent gain of 1.5 dB typical. This highly optimized performance - which is believed to be unique on the market - provides the first practical building block for the development of flexible and cost-effective PONs based on wavelength division multiplexing (WDM).
"A lot of PON development is in progress, but for this kind of optical transmission architecture we're seeing engineers using prototypes based on standard SOAs with less than optimal anti-reflection characteristics," says Neil Weston of CIP. "This reflective SOA offers application-specific performance to support development and trials, and is based on a monolithic device design that is well suited to high-yield, low-cost volume manufacture."
The SOA-RL-OEC-1550 has ultra-low front facet reflectivity (<10-5), and is ideal as a reflective colourless amplifying modulator in WDM-PON schemes, or as a gain block for external cavity lasers. The device employs CIP's proprietary InP buried heterostructure design which delivers very high light confinement. It is available in a 7-pin butterfly/SMA package with a thermistor, thermo-electric cooler, singlemode fiber pigtail and a 50-ohm input impedance matching circuit, or as a custom chip-on-carrier product.
Key specifications include a small signal gain of 20 dB typical over a wavelength range from 1530 to 1570 nm, gain ripple of 0.5 dB typical/1.5 dB maximum, polarization dependent gain of 1.5 db typical/3 db maximum, and a data modulation rate of up to 1.5 Gbits/sec.
CIP also offers a highly polarization-selective variant of the device, the SOA-R-OEC-1550.