Short pulse solid state Lasers and amplifiers Beyond 2 µm – SPLENDID2

SPLENDID2 project addresses contemporary challenges by proposing innovative laser solutions in the mid-infrared (MIR), necessary for the generalization of material processing technologies for soft materials processing in industry as well as for ablation and cutting of tissues in surgery. These developments are also highly desired for scientific applications, particularly for strong field physics. This 36-month collaborative project combines the original and complementary contributions of four academic partners CIMAP, IRCP, LCF and CORIA. The partners are working on the development of ultrafast oscillators and efficient amplifiers with unprecedented performances in terms of energy and high repetition rates, operating in the femtosecond regime in the MIR beyond 2 microns, in particular around 2.3 and 2.8 µm. To date, there are no such solid state lasers and/or amplifiers and this research program would be an essential support to allow the consortium to become the pioneers in this field. The lasers and amplifiers that will be studied in this project, will be based on Er or Tm doped CaF2, YLF and CALGO crystals, as well as Y2O3 transparent ceramics. The impact of this project in case of success lies in the possibility to develop innovative experimental tools for fundamental research and could lead at medium term to the development of novel scientific and medical instrumentation.
To build high energy laser systems emitting in the MIR between 2 and 3 µm, we propose to explore two wavelength ranges by exploiting very promising laser crystals. The first part of the project is based on the exploitation of the 2.3 µm laser transition of Tm ions which presents a more interesting alternative than the standard transition centered at 1.9 µm which coincides with the water vapor absorption band. The development of this source will benefit from the deep know-how of the CIMAP and the IRCP on fluoride and oxide-based laser materials. The generation of sub-ps pulses approaching the mJ energy level is expected at this wavelength by exploiting adapted laser architectures that will draw on the expertise of the LCF and CORIA. The development of hybrid architectures combining fiber-based seeders with bulk-crystal amplifiers will be preferred. The second part of the SPLENDID2 aims to develop mode-locked laser sources and power amplifiers emitting around 2.8 µm by exploiting erbium-doped host crystals. Our scientific and technological efforts will focus on the exploration of different laser architectures including waveguides which are very suitable for the production of very high repetition rate pulse trains. This will pass through the development of different strategies for dispersion management and the study of different mode locking mechanisms in these oscillators. If successful, the results will be a remarkable breakthrough in the field by paving the way for the construction of highly integrated ultrafast lasers based on an original growth technology.
Our approach based on the control of the whole manufacturing chain from material growth to assembly and qualification of original laser sources in the MIR has a great potential for valorization. We will pay particular attention to patentability so as to insure industrial exploitation of our innovations.