The television channel Castilla y León Television publishes on its website the news about the meeting of the expert council of the ATTOSTRUCTURA project.
You can read the press release and watch the video on their website.
Next August will be thirty months since the ATTOSTRUCTURA project began, which means that half of its duration has already elapsed.
For this reason, the first meeting of the project’s scientific advisory committee has been held. The committee, made up of external researchers who are experts in the different fields of the project, has the objective of evaluating the development of the project, the results obtained to date and, if necessary, proposing changes or modifications in the lines of research. In this way, it is intended to ensure that the project achieves the best possible results while maintaining the highest level of excellence.
The members of the scientific advisory committee are:
The meeting, which took place on Friday, July 22, in the Board Room of the Faculty of Sciences, began with an open-door session in which the status of the project and the main results obtained to date were presented. The videos of that session will be available on the project website.
On the occasion of the meeting, Carlos Hernández García (principal investigator of the project) speaks in this video recorded by the audiovisual services of the University of Salamanca, about the project, its objectives and the results obtained.
#InvestigadoresDeLaUSAL | Carlos Hernández, investigador del GIR Aplicaciones de los Láseres y Fotónica de la USAL (@OpticaExtrema), explica en qué consiste el proyecto europeo ATTOSTRUCTURA, financiado por el @ERC_Research. pic.twitter.com/pKgAX1kF6E
— Universidad de Salamanca (@usal) July 25, 2022
From July 11 to 15, the XXXVIII Biennial Meeting of the Royal Spanish Society of Physics was held. The Laser and Photonics Applications group (ALF – USAL) has participated in said biennial, presenting some of the most recent results of the research it is currently carrying out.
The works presented were:
In addition, Carlos Hernández García participated in the organization of the congress as part of the scientific committee.
The OSAL Student Chapter of the University of Salamanca has been awarded second place at the Foton 2022 Awards in the Foton Emitted category, for its informative video “The colors in soap bubbles”.
The jury has positively valued “his ability to disclose to the general public, explaining the operation of the phenomenon of interference of light with an accessible and attractive example” in addition to his creativity when showing the colors that are produced in the bubbles.
The video explains the thin film interference phenomenon, which is responsible for the appearance of colors in soap bubbles and which also appears in other situations such as puddles or butterfly wings.
You can see this video (and other very interesting ones too) on the page of the OSAL Student Chapter of Salamanca and read the complete review of the award on the CSIC website.
Sterling silver jewelry, rose gold with exclusive designs, rings, earrings, bracelets… made out of light? Like a high fashion jewelry workshop, the Laser and Photonics Applications research group of the University of Salamanca (ALF-USAL) focuses its efforts on designing light jewels through non-linear optics. Jewels, not only for their beauty in the form of high-frequency lasers, but also for their usefulness in observing and controlling unknown processes in nature. In fact, the design of coherent and high-frequency laser light beams (towards the X-rays) has become a unique tool to access processes that take place in very small sizes (nanometers) and in very short times (trillionths of seconds).
The theoretical-experimental collaboration between ALF-USAL and the group of Profs. Murnane and Kapteyn at the University of Colorado at Boulder (USA) have been developing fine jewelry for the last few years. After generating high-frequency rings with properties never seen before (see references [1,2]), the researchers have gone a step further, entering the world of necklaces. The design of an infrared laser in the form of a necklace allows to control the frequency and divergence (or spatial size) of the X-rays that are produced after the non-linear process of high-order harmonic generation. In this work, published in the journal Science Advances, the researchers also demonstrate that the spectral content of these X-ray lasers can be calibrated by means of the number of beads in the necklace. One more step in the high fashion jewelry with lasers that tries to help in the understanding of the fastest processes of nature.
More information in:
“Necklace-structured high harmonic generation for low-divergence, soft X-ray harmonic combs with tunable line spacing”, Laura Rego, Nathan J. Brooks, Quynh L. D. Nguyen, Julio San Román, Iona Binnie, Luis Plaja, Henry C. Kapteyn, Margaret M. Murnane, Carlos Hernández-García, Science Advances 8, eabj7380 (2022).
References::
[1] “Generation of extreme-ultraviolet beams with time-varying orbital angular momentum”, Laura Rego, Kevin M Dorney, Nathan J Brooks, Quynh Nguyen, Chen-Ting Liao, Julio San Román, David E Couch, Allison Liu, Emilio Pisanty, Maciej Lewenstein, Luis Plaja, Henry C Kapteyn, Margaret M Murnane, Carlos Hernández-García, Science 364, eaaw9486 (2019).
[2] “Controlling the polarization and vortex charge of attosecond high-harmonic beams via simultaneous spin-orbit momentum conservation”, Kevin M. Dorney, Laura Rego, Nathan J. Brooks, Julio San Román, Chen-Ting Liao, Jennifer L. Ellis, Dmitriy Zusin, Christian Gentry, Quynh L. Nguyen, Justin. M. Shaw, Antonio Picón, Luis Plaja, Henry C. Kapteyn, Margaret M. Murnane, Carlos Hernández-García, Nature Photonics 13, 123–130 (2019).
On the occasion of the proclamation of May 16 as “International Day of Light and Light-Based Technologies” by the United Nations Organization, the Master’s Degree in Laser Physics and Technology” announces the IV edition of the Photo Contest “Day of the light”.
In the organization of the contest and formation of the jury participate:
The contest is open to undergraduate, master’s or doctoral students, professors and members of the university community of the University of Salamanca and the University of Valladolid, as well as graduates of the Master’s Degree in Laser Physics and Technology who are not part of the jur
The participation period is open until May 3. Each participant can send up to two photographs to each of the established categories:
4 prizes will be awarded:
In addition, all the winners will receive one year of free subscription to the Royal Spanish Physics Society with online access to the Physics Journal. The winning photographs will be published in the Pure and Applied Optics magazine of the Spanish Optical Society (SEDOPTICA).
The complete rules of the competition are available on the website of the Master’s Degree in Physics and Technology of Lasers (laser.usal.es/posgrado)
Our friends and frequent collaborators from JILA (University of Colorado) echo the paper “Necklace-structured high-harmonic generation for low-divergence, soft x-ray harmonic combs with tunable line spacing” recently published in ScienceAdvances.
You can read his review at the following link: https://jila.colorado.edu/news-events/articles/necklace-made-doughnuts
More information at:
In spite of having an extremely short life, of just a few quadrillionths of a second, ultrashort femtosecond laser pulses have become an indispensable tool in many areas of science and technology, as they allow to probe the most fundamental properties of matter on ultrafast time scales.
Generating these such short pulses of light in a controlled manner and with a good quality is not an easy task, and in the last years various strategies have been proposed. The main idea is to generate a very wide light spectrum, made up of many frequencies, by means of nonlinear processes starting from a narrower one, and then correcting its phase to synchronize all the frequencies, giving rise to an ultrashort pulse. A widely used method to achieve this large spectral broadening is to propagate an initial light pulse through a hollow cylindrical fiber filled with a gas. In this case, one of the parameters that most influences the propagation is the pressure of the filling gas, which allows for a continuous tuning of the dispersion and the intensity of the nonlinear effects experienced by the pulse. In particular, if the fiber and gas parameters are carefully chosen, the incident pulse can broaden its spectrum while correcting its phase due to the interaction between the linear and nonlinear processes. In this way, the pulse reduces its duration on its own, in a process known as soliton self-compression.
Usually, these experiments are carried out keeping the gas at constant pressure, homogeneously filling the fiber. However, in one of our latest studies we have shown that applying a decreasing pressure gradient, causing the gas concentration to gradually decrease during propagation, can improve the quality of the self-compressed pulses and reduce their duration even more than constant pressure.
You can look up for all the details of this work at:
F. Galán, E. C. Jarque, and J. San Roman, Optimization of pulse self-compression in hollow capillary fibers using decreasing pressure gradients, Optics Express 30(5), 6755–6767 (2022). https://doi.org/10.1364/OE.451264
On February 2nd, Carlos Hernández García, Ramón y Cajal researcher, member of the Laser and Photonic Applications research group and principal investigator of the Attostructura project (ERC 851201) gave the seminar “Structuring ultrafast laser light through highly nonlinear physics” within the cycle of seminars of the Rocasolano Institute of the CSIC.
The degree of control we have achieved over the manipulation of light is truly amazing. Initiated by our Greek ancestors using mirrors to guide light, we live in a world where the most advanced laser technology allows us to create and sculpt light beams with great precision. In particular, nowadays we can create ultrashort attosecond pulses (with durations of trillionths of a second), of very high frequencies (up to the soft X-rays), and with increasingly complex spatial structures thanks to our ability to harness their angular momentum. In this talk we will review our recent work in the generation of structured ultrashort laser pulses. Thanks to the highly nonlinear process of high harmonic generation, we can tailor the spin and orbital angular momentum properties of extreme ultraviolet/soft x-ray laser pulses directly at their generation. By properly controlling the process of high harmonic generation, from the driving laser beam to the target (gas or solid), different families of structured ultrashort laser beams can be created: self-torqued beams, vector-vortex beams, tunable high-frequency combs, or hexagonal harmonic beams. These new optical tools allow us to fantasize of new laser-matter interaction processes at the nanoscale, whose physical laws are yet to be discovered. For example, structured laser pulses offer an appealing alternative to study sub-femtosecond magnetization dynamics, where a complete understanding of the electronic and spin interactions remains unexplored
You can see the full video of the seminar on this page or on Youtube channel of the Rocasolano Institute.
Jorge Souto, from the University of Valladolid, will give the seminar entitled “Degradation of laser diodes: physical models and resolution by finite element methods (FEM)” on December 14 at 11:30.
The seminar is open to all who want to attend, it will take place in the Aula Sancho Guimerá (Exactas) of the Faculty of Sciences of the University of Salamanca.
The entire seminar will be uploaded to this website and to the YouTube channel of the ALF-USAL group.