Report on the QuantumLaP project will be presented as a 1h seminar at Hilase Centre, on the 28th of March 2017, 2pm.

Development of predictive tools for the laser tailoring of material properties

Using intense laser beams, materials can be functionalized by inducing local modifications of the surface topography and/or the band gap, and by triggering local chemical reactions (oxidation, bond restructuring, etc.). Impressive capabilities of ultrashort laser pulses have already enabled the emergence of a wide range of real-world applications, such as surface colorizing and wetting engineering. Novel possibilities are now being explored toward tabletop particle accelerators, high-harmonic generation, potentials of using mixed laser beams. Fundamental novelty behind these applications lies in the laser-induced modification of the electronic structure which is still poorly understood because of lack of ultrafast probing experimental techniques with nanoscale spatial resolution. In this context, improvement of available theories and modeling tools used for studying laser processing is highly demanded for bringing more understanding and accurate predicting of material evolution at nanoscale in a wide range of laser parameters. Developing a bridge between the classical descriptions with first-principle theories is an essential part of advancing laser processing technologies.

In this seminar, I will present how modeling the behavior of electron dynamics upon high intensity enables the possibility to perform reliable predictions for single- and bi-color laser irradiation of semiconductors [https://www.quantumlap.eu/]. Two different scales of the same physics will be addressed: modeling of the experimental effects (such as transient reflectivity change), and the corresponding quantum processes (time-resolved dynamics of electron excitation in bandgap material).

A new collaborative paper was recently published, where simulation code on Surface Plasmon Polaritons was used to compare with experimental results on laser induced nanostructures periods for several laser wavelengths.

To meet requirements from Horizon 2020, we also submitted the paper on arXiv.

Maragkaki et al, Wavelength Dependence of Picosecond Laser-Induced Periodic Surface Structures on Copper, Applied Surface Science, DOI: 10.1016/j.apsusc.2017.02.068 (IF 2015: 3.15).

Our new paper together with several famous authors in modeling the laser-matter interaction was just published online in MRS Bulletin (impact factor 6.06). And we are proud to see that it actually made the cover of the journal. :o)
Shugaev et al, MRS Bulletin 41, 960 (2016)

The 6th international LIPSS (Laser Induced Perodic Surface Structures) workshop was held in FORTH University of Heraklion, in Crete.

The latest developments of the theory on Surface Plasmon Polaritons (SPP) adapted for laser ablation conditions were presented in an invited talk, after 1st publication of the project appeared online. The future open-source tool for performing predictions of surface nanostructuring by lasers was promoted.

An abstract of the presented work is available on the BAM repository.

I attended the Octopus Developer Meeting 2016, held in Max Planck Institute for Structure and Dynamics of Matter (Hamburg), and was proposed to give an oral presentation.

More details are available there.

The “Benasque school of physics” hosts famous physics school all along the year. This year, I could attend to the “Time-Dependent Density Functional Theory: Prospects and Application” for a duration of 2 weeks. The school is composed of 1 week of lessons, including the week-end, and one week of workshop to get a view on the latest developments in the field of TD-DFT and beyond.

See the website for more information.

Shanghai TV tower

I got invited oral presentation to present my latest results of continuum modeling in Si irradiated by femtosecond lasers at the Progress in Electromagnetic Research Symposium, held in Shanghai (China).

Link to the conference: http://www.piers.org/piers2016Shanghai/

Title: Transient Electron-hole Dynamics at the Surface of Silicon upon Femtosecond Laser Irradiation in Modification Regime

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On July 10, 2016, Dr. Thibault J.-Y. Derrien and Dr. Yoann Levy travelled to Venice, Italy for the 5^th International School “Lasers in Materials Science” on the Isola de San Servolo, home to Venice International University.

The school was directed by Maria Dinescu (National Institute for Laser, Plasma and Radiation Physics, Bucharest, Romania), David B. Geohegan (Oak Ridge National Laboratory, USA), Antonio Miotello (Trento University, Italy), and Paolo M. Ossi (Politecnico di Milano, Italy). The School provided undergraduate students, PhD students and young research scientists with a wide opportunity to learn on fundamental roots of the interactions of laser light with different materials that are usually missed in traditional programs. The attendees were offered with 18 lectures from world-leading scientists, ranging from fundamentals of laser-matter interaction to scientific and industrial applications in various fields including new material production and bio-medicine.

One of the lectures was given by the RP4 Leader Nadezhda Bulgakova. The school also provided excellent opportunities of interactions and establishing cooperation with other researchers and colleagues working in similar, yet diverging fields.

Yoann presented work on Temperature relaxation after modulated absorption of femtosecond laser pulse in gold and fused silica in the LIPSS formation regime and Thibault presented work on the Role of electron-hole pair dynamics in modification of silicon upon femtosecond laser irradiation.

For his excellent work and presentation, Thibault Derrien was awarded the 2^nd place among “Rising Stars” (Third Year PhD and Post-doc researchers) in the schools poster competition in memory of Prof. Roger Kelly.

Official announcement can be found here.

Biography of Roger Kelly can be found here.