The main objectives of the Project are the understanding of the underlying physical mechanisms relevant to VCSEL operation, the subsequent improvement of their efficiency and the transfer of this knowledge to VCSEL based systems.

The research objectives can be broken down in two categories,
I characterisation , modelling and testing of the models
II fabrication and assessments of devices.

The research objectives for the two main sections are the following:
I 1 - characterisation modelling and test of the influence of fabrication techniques (cavity design, detuning) and internal parameters (Alpha factor, amplification/ absorption, thermal properties) on the laser dynamical properties.
I 2 - Characterisation modelling and test of the effects that influence the performance of VCSELs in communication systems, in particular polarisation and pattern dynamics and coupling between them, chirp, feedback.
I 3 - Characterisation modelling and test of nonlinear and collective effects, including polarisation, co-operative phenomena, stationary patterns and dynamics, self-organised structures (cavity solitons) in broad-area VCSELs and arrays.
I 4 - Characterisation modelling and control of intensity and polarisation noise and of polarisation and transverse modes correlation down to the quantum level.
I 5 - Control of nonlinear effects by means of feedback and optical injection and pumping.
Improvement of the system performance by exploiting the special features (polarisation and pattern switching, localised structures) of VCSELs.
I 6 - Definition of the AM/FM response and of electrical characteristics of VCSELs.
Definition of time-response and switching characteristics of new kind of VCSELs (based on new materials, quantum wires, quantum dots, new geometries).

II 1 - Device optimisation of near-infrared (0.75-0.98mm) lasers for their use in communication and data processing systems. The optimisation includes low threshold and high efficiency, low noise, control of pattern and polarisation, higher modulation frequency, ultrafast switching.
II 2 - Laser fabrication using novel III-V materials, extending the wavelength (1.3mm, red), exploiting quantum wire and quantum dot structures for increased gain and efficiency, exploring new laser geometries for a better polarisation stability and feedback insensitivity.
II 3 - Assessment of new devices.