Feb 28 2008
Hitachi, Ltd. and Opnext, Inc. today announced the first wide temperature range operation of 1310-nm 25Gbit/s EA-DFB lasers for 100Gbit Ethernet 10km single-mode fiber (SMF) application at OFC/NFOEC 2008.
A study by the IEEE HSSG (High Speed Study Group) showed that by the year 2010, the bandwidth required in core networking will be best satisfied by 100Gbit/s interfaces. Furthermore, bandwidth needs are expected to double every eighteen months resulting in demand for multi-port 100Gbit/s systems. In the IEEE 802.3ba taskforce, a 10km SMF (single mode fiber) 100Gbit/s Ethernet specification is being discussed. For this application, 1310-nm four channels by 25Gbit/s WDM (wavelength division multiplexing) transmission is the most attractive technology. One of the technology challenges is to achieve 1310-nm 25Gbit/s WDM optical devices. CWDM (course wavelength division multiplexing) technology is expected to be the most cost effective solution due to the wide wavelength pitch that enables 100 percent of wavelength yield and less strict or no temperature control.
Hitachi and Opnext have demonstrated EA-DFB lasers operating at 25Gbit/s with wavelengths of 1290-, 1310-, 1330- and 1350-nm. The 25Gbit/s operation was achieved using high speed device technology which has been already confirmed in 1550-nm 40Gbit/s EA-DFB lasers currently used commercially in 40Gbit/s transceivers. A wide temperature range operation from 0ºC to 85ºC was also reported. This was achieved using advanced aluminum-based material system in the EA (electro-absorption) modulator section. This semiconductor material system has a temperature tolerant band-gap structure which decreases the temperature dependent performance of the modulator.
These EA-DFB (electro-absorption modulator with integrated distributed feedback laser) lasers demonstrate the technical feasibility of the CWDM grid which achieves low cost 100Gbit/s optical transceiver modules with low power consumption and compact size which is expected to accelerate the adoption of 100Gbit/s interfaces in the network.
“The demonstrated 25Gbit/s 1310-nm CWDM EA-DFB lasers were achieved based on Hitachi’s advanced technology for uncooled and high speed lasers which has already been demonstrated in previous work of uncooled 10Gbit/s and cooled 40Gbit/s EA-DFB lasers,” said Masahiko Aoki, Central Research Laboratories, Hitachi, Ltd. “We believe that uncooled operation is the key to achieve small and low cost 100GbE transceivers for LAN application.”
The post deadline paper detailing this EA-DFB laser results will be presented at OFC/NFOEC 2008 being held February 26-28, at the San Diego Convention Center, San Diego, California.
Opnext will be located at Booth #1216 at OFC/NFOEC 2008 being held February 26-28, at the San Diego Convention Center, San Diego, California.