Quantum DOT laser devices for optoelectronic information COMmunication

The DOTCOM consortium of universities, research institutions and industrial companies aims to realise and investigate innovative optoelectronic quantum dot semiconductor lasers. The project spans the entire spectrum from materials development via device fabrication to systems testing. State-of-the-art methods will be employed for growing quantum dot material fibre 1300 nm and 1550 nm emission wavelength. Calculations of material properties and microscopic device simulation will together with advanced experimental investigation optimise the quantum dot nano-technologies and guide the design of laser devices.

Objectives:
The central objective of the DOTCOM project is the development of innovative quantum dot lasers based on GaAs quantum dot wafer technology. To fabricate high quality quantum dots for 1300 nm and 1550 nm emission wavelength in a controlled and reproducible manner the MBE and MOCVD materials technologies will be employed. They are to be assessed with respect to reliability, market applicability and environmental friendliness. Calculations of electronic quantum dot properties as well as experimental characterisation will allow an optimisation of the growth process. For highest information system flexibility high-performance lasers will be designed, realised and optimised by comparison with simulation and experiment. Based on this novel 1300 and 1550 nm quantum dot laser technology testbeds for optoelectronic metropolitan and local area information systems will be realised and their characteristics analysed.

Work description:
The unique combination of expertise of the DOTCOM partners combines exploratory MBE and MOCVD epitaxial quantum dot material development and characterisation, quantum dot laser device fabrication and optimisation as well as opto-electronic information system realisation and testing. New theories and electronic structure calculations as well as state-of-the-art experimental characterisation will provide direct feedback for optimisation of the growth process. To meet the ultra broad-band system requirements of next-generation optoelectronic information networks, innovative quantum dot lasers and amplifiers will be fabricated. The lasers will be optimised in close comparison with microscopic simulations and ultra-short time experimental characterisation. Laser modules will be characterised and integrated into a laboratory testbed with capability for changing module temperature and fibre type and length at speeds of 2.5 Gb/s and 10 Gb/s. 1300 nm lasers will be assessed to verify compliance with datacom standards such as the proposed IEEE 10 Gigabit Ethernet standard. 1550 nm lasers will be assessed in the context of telecommunications networks with the emphasis on extended reach. Quantum dot semiconductor optical amplifiers at both 1300 nm and 1550 nm will be assessed in the systems context with e.g. saturation power, noise performance, linearity. The suitability of the semiconductor optical amplifiers as both line and pre-amplifiers will be evaluated. Amplified systems at both wavelength will be theoretically and experimentally demonstrated and the limits for amplified transmission will be determined.