Final Report Summary - ULTRALASER (ULTRALONG FIBRE LASERS)
Nowadays, lasers have become ubiquitous devices equally important in fundamental science, engineering technologies and in a range of practical applications. The progress in laser science and technology is driven by a variety of new applications that these emerging laser systems can open-up. This progress is facilitated by advances in material science, achievements in technology and by the improvement in our understanding of the fundamental laser principles and physics underlying the operation and performance of new types of lasers.
The ULTRALASER project has developed new science and technologies based on the concept of ultra-long lasers. The research included theoretical, numerical and experimental studies of various types of ultra-long fibre lasers and a variety of their immediate and future applications. Lasers are usually considered as sources of coherent light. However, an ultra-long laser cavity implemented in optical fibre can also be thought of as a special type of transmission medium. Such an ultra-long resonator, which can have a length scale of several hundreds of kilometres, is not only an exciting new physical system, but it might also lead to a radical new outlook on transmission of information and secure communications
The length of the cavity is one of the fundamental laser characteristics. As the result of ULTRALASER, a large variety of different types of ultralong laser have been proposed and demonstrated. Innovative designs of ultralong laser based on new underlying physics offer opportunities for creating systems with non-incremental changes of performance characteristics leading to new platform for disruptive progress for telecommunications, spectroscopy, global positioning systems, material processing and bio-medical imaging.
ULTRALASER has explored novel configurations of mode-locked lasers, including isolator-free cavities, and various gain fibres to support generation in 1–2 micron wavelength range. A novel spontaneous pattern formation mechanism in ultralong lasers, due to periodic zig-zag modulation of losses for different spectral components has been discovered. ULTRALASER led to development of new measurement and signal processing techniques to characterise the partially mode-locked and stochastic generation, uncovering its complex intra-cavity dynamics of radiation with localized structures. The project has advanced technology of lasers with greatly extended cavity length and with combination of Raman and rare-earth doped fibre gains to reach high-energy laser generation.
New type of random distributed feedback lasers, exploiting multiple Rayleigh scattering in fibre core, to generate coherent light in a long fibre amplified through the Raman effect was proposed and developed. Multi-wavelength lasing and high quantum conversion efficiency have been demonstrated.
The research results were adapted to real world applications, such as sensing and telecommunications. Using originally designed and engineered novel low noise CW and pulsed pumps for Raman amplification, we have demonstrated ultralong broadband quasi-lossless signal propagation with low signal variation. The project made strong contribution into development of the nonlinear Fourier transform technique that requires quasi-lossless transmission spans. We have also demonstrated the gyroscopic effect in the rotating femtosecond ring bidirectional fibre laser.
The investigation of ultralong lasers stimulates flow of new ideas from research fields of turbulence and disordered systems into the laser science. Ultralong fibre laser is an excellent test-bed for studying optical wave turbulence, optical rogue waves and disordered systems in photonic experiments providing high precision of measurements.
Overall, the project advanced the physics underlying operation of fibre lasers and revealed new opportunities and directions in high-speed fibre communications, secure communications, laser physics and other fields of science and technology.
The ULTRALASER project has developed new science and technologies based on the concept of ultra-long lasers. The research included theoretical, numerical and experimental studies of various types of ultra-long fibre lasers and a variety of their immediate and future applications. Lasers are usually considered as sources of coherent light. However, an ultra-long laser cavity implemented in optical fibre can also be thought of as a special type of transmission medium. Such an ultra-long resonator, which can have a length scale of several hundreds of kilometres, is not only an exciting new physical system, but it might also lead to a radical new outlook on transmission of information and secure communications
The length of the cavity is one of the fundamental laser characteristics. As the result of ULTRALASER, a large variety of different types of ultralong laser have been proposed and demonstrated. Innovative designs of ultralong laser based on new underlying physics offer opportunities for creating systems with non-incremental changes of performance characteristics leading to new platform for disruptive progress for telecommunications, spectroscopy, global positioning systems, material processing and bio-medical imaging.
ULTRALASER has explored novel configurations of mode-locked lasers, including isolator-free cavities, and various gain fibres to support generation in 1–2 micron wavelength range. A novel spontaneous pattern formation mechanism in ultralong lasers, due to periodic zig-zag modulation of losses for different spectral components has been discovered. ULTRALASER led to development of new measurement and signal processing techniques to characterise the partially mode-locked and stochastic generation, uncovering its complex intra-cavity dynamics of radiation with localized structures. The project has advanced technology of lasers with greatly extended cavity length and with combination of Raman and rare-earth doped fibre gains to reach high-energy laser generation.
New type of random distributed feedback lasers, exploiting multiple Rayleigh scattering in fibre core, to generate coherent light in a long fibre amplified through the Raman effect was proposed and developed. Multi-wavelength lasing and high quantum conversion efficiency have been demonstrated.
The research results were adapted to real world applications, such as sensing and telecommunications. Using originally designed and engineered novel low noise CW and pulsed pumps for Raman amplification, we have demonstrated ultralong broadband quasi-lossless signal propagation with low signal variation. The project made strong contribution into development of the nonlinear Fourier transform technique that requires quasi-lossless transmission spans. We have also demonstrated the gyroscopic effect in the rotating femtosecond ring bidirectional fibre laser.
The investigation of ultralong lasers stimulates flow of new ideas from research fields of turbulence and disordered systems into the laser science. Ultralong fibre laser is an excellent test-bed for studying optical wave turbulence, optical rogue waves and disordered systems in photonic experiments providing high precision of measurements.
Overall, the project advanced the physics underlying operation of fibre lasers and revealed new opportunities and directions in high-speed fibre communications, secure communications, laser physics and other fields of science and technology.