Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - MINDFLY (Mid-IR ultrabroadbaNd thulium-doped Fiber Laser sYstems)

Teaser

The Fellowship, entitled “Mid-IR ultrabroadbaNd thulium-doped Fibre Laser sYstems” (MINDFLY) has successfully reached its ultimate goal of training a talented researcher, Dr. Maria Chernusheva, through a research project in the fast-growing field of science, technology and...

Summary

The Fellowship, entitled “Mid-IR ultrabroadbaNd thulium-doped Fibre Laser sYstems” (MINDFLY) has successfully reached its ultimate goal of training a talented researcher, Dr. Maria Chernusheva, through a research project in the fast-growing field of science, technology and industrial applications of fibre lasers, material science and nonlinear optics. The success of the multidisciplinary project has led to a number of disruptive innovations in photonics. Particularly, the project has led to discovering of new regimes of ultrafast fibre laser generation at 1550 and 1900 nm wavelength range, developing of new numerical codes for ultrashort pulse formation and propagation, thorough investigation of carbon nanotubes (CNT) properties as saturable absorber, as well as new designing of novel rotation sensing ultrafast laser gyroscopes.
The overall objectives of the project are: (i) Broadening of the Fellow’s expertise; (ii) Development of novel theoretical models for MLFLs and ultrabroadband SC generation; (iii) Design an advanced technique for high-stable laser mode-locking; (iv) Development of the nonlinear science techniques for the SC generation applying novel types of optical fibres; and (v) Applications of the laser systems for optical frequency metrology, sensing, and optical communications.
The development of Mid-IR fibre lasers and sensors contributes to the EU economy by itself, as a largely growing industrial sector, which market is anticipated to increase tenfold in 5 years and reach $7 billion by 2019. The demonstrated through the project ultrafast fibre laser systems overtake earlier reported state-of-the-art results, hence increasing the EU Research Area competitiveness in the world. Being applied in medicine, the burst-mode operating ultrashot pulse fibre laser has high potential to be applied for high-precision soft and fragile tissue ablation, which does not induce collateral damage and heat accumulation, therefore, significantly enhancing medical capabilities. The accurate measurements of velocities and relative motion, also used for GPS, require high precision and compact gyroscopes. The demonstrated elegant configuration of ultrafast fibre laser gyroscope has a performance, which can be tailored to one of large ring gyroscopes, therefore can be applied in seismological measurements or for detection of Earth axis wobble.

Work performed

WP 1 the overall training activities and knowledge transfer. Work carried:
Courses attended (complementary skills):
1. “Writing and submitting a successful fellowship” (03 Mar 2016) Aston Uni
2. “Developing research: Writing Research Proposals Programme” (19 Jan – 13 Jun 2016)
3. Individual English Language Tutorials, the Centre for English Language and Communication at Aston (10 May 13 Jun 2016)
4. Purchase Orders – Raising on Agresso (27 July 2017)
5. Be a Conversation starter: Engaging with the media for academics (11 Oct 2017)

WP 2 Development of the new theoretical models and the in-house solver software to model MLFL and SC generation. Work carried:
1) Numerical modelling of the hybrid mode-locked laser, incorporating both double-walled carbon nanotubes and nonlinear polarisation evolution as saturable absorbers with different relaxation time
2) Simulation of Thulium-doped fibre laser with high normal intracavity dispersion and high nonlinearity has demonstrated new regimes of generation.
3) Numerical simulation of bidirectional Erbium-doped fibre laser, operating as angular velocity sensor.
Disseminations: Sci Rep. 7: 44314, 2017; International Conference on Laser Optic 2016)

WP 3 Design an advanced technique for high-stable laser mode- locking. Work carried:
1) Single and double walled carbon nanotubes performance as a SA in Thulium-doped fibre lasers have been compared.
2) The thermal damage threshold of CNT-polymer samples has been studied.
3) The ink-jet technology for printing thin layers of pure SWNT solution (without polymer) onto the edge of fibre ferrule has been studied.
4) The surfactant (sodium dodecylbenzene sulfonate) concentration in final solution for SWNT/polymer sample has been analysed for potential optimisation of the ultrafast laser performance.
Dissemination: Sci Rep. 7: 44314, 2017

WP 4 MLFL optimisation by regulating intracavity dispersion and nonlinearity. Work carried:
1) Experimental investigation of isolator-free ring configuration of Erbium-doped ultrafast fibre laser, mode-locked with coaction of SWNT-SA and nonlinear polarisation evolution.
2) Using hybrid mode-locking scheme with DWNTs and NPE, the generation of conventional soliton pulses and bound states of solitons in the Tm-doped fibre laser has been experimentally demonstrated.
3) The dispersion control in the ring thulium-doped fibre laser mode-locked with SWNT has been realised using highly doped germanium-silica fibre (Ge concentration ~75%).
4) The elongation of the laser cavity and evolution of the output parameters has been studied.
Dissemination: Optics express 24 (14), 15721-15729, proceeding of Photon-16 Conference and International Conference on Laser Optic 2016; Sci Rep. 7: 44314, 2017, proceedings ICONO-LAT 2016

WP 5 Supercontinuum generation. Due to cropping of Fellowship duration, the work package has not been implemented.

WP6 Application of the developed ultrabroadband laser systems. Work carried:
The gyroscopic effect has been demonstrated by measuring the gyroscopic shift in the time domain.
Dissemination: proceedings of CLEO-Europe 2017; submitted to Conference Photonics West 2018

Other publications are being prepared for submission or submitted (under review)

Final results

1) Justification of high potential of carbon nanotubes for robust and reliable high power laser operation for wide range of industrial application
2) Development of ink-jet printing technology for carbon nanotubes implementation on optical fibre core
3) Demonstration of the switching mechanism between generation directions in isolator-free ring fibre laser. This allows a single laser to operate as two separate femtosecond lasers simultaneously, which can find potential application in imaging techniques and sensing, dramatically reducing the price of the final measurement system.
4) Systematic analysis of bound-state solitons generation, examination of the key role of the relaxation time of saturable absorber using the example of single- and double-walled carbon nanotubes. It was proved that faster relaxation time of double-walled carbon nanotubes allows generation of robust soliton molecules.
5) demonstration of quasi-lossless ultralong erbium-doped fibre laser and achievement of high power burst generation
6) Spatio-temporal dynamics of the pulse in bidirectional erbium-doped fibre laser takes pulse relative motion as an advantage by analysing slow time evolution of pulses co-ordinates for gyroscopic measurements of the angular velocities of the laser cavity rotation. The presented configuration can measure the difference of angular velocities of less than 6.6·10-4 rad/sec, which is order of magnitude better than beat-note frequency measurements based measurements via mode-locked fibre laser gyroscopes. The sensitivity can be further improved by stabilising rotation platform from parasitic vibrations and better control of mode-locked laser generation regime.

Website & more info

More info: http://www.aston.ac.uk/eas/research/groups/photonics/aipt-research-projects/.