Projects / Programmes
Triggering forbidden phenomena with twisted light and particle beams
| Code |
Science |
Field |
Subfield |
| 1.02.00 |
Natural sciences and mathematics |
Physics |
|
| Code |
Science |
Field |
| P230 |
Natural sciences and mathematics |
Atomic and molecular physics |
| Code |
Science |
Field |
| 1.03 |
Natural Sciences |
Physical sciences |
photon and electron beams with topological charge, high-order harmonic generation, free electron laser
Researchers (8)
Organisations (2)
Abstract
Probing the microscopic properties of matter through the interaction with photons and other particles provides invaluable data used in a wide range of scientific disciplines, such as chemistry, biology, or physics, and in several technological fields. These particles exchange energy, linear momentum, and (spin and orbital) angular momentum with atoms on their way through matter. Particularly the study of spin and orbital angular momentum exchange is of high importance since it provides data on the local symmetry, chirality, and magnetic properties of the sample under investigation. Apart from the spin angular momentum (SAM), which is related to the polarisation state of the particles incident on the target, a particle beam may carry a well-defined orbital angular momentum (OAM). The OAM value depends on the spatial profile of the beam. Photon beams with OAM are nowadays routinely produced in the visible spectral range. However, extending the generation process to the extreme ultraviolet (XUV) region, which would allow for a detailed structural analysis of matter, is presently the subject of intense research activities carried out by several groups around the world. On the other hand, electron beams carrying OAM have only recently been successfully generated. Various alternative generation schemes have been proposed, but have not yet been implemented. The aim of this project is to demonstrate the capability of ultra-fast laser-seeded sources – high-order harmonic generation (HHG) in gas and free electron lasers (FELs) – to produce coherent photon beams that carry OAM and to study the properties of the generated light. Furthermore, we propose to develop a source capable of generating electron beams, which carry OAM, and characterise the beams' properties. Finally, we will use the generated photon and electron beams to perform proof-of-principle experiments on atomic targets, which will pave the way to complete new applications both in fundamental and applied physics. The proposed plan will be implemented jointly by the team of the Laboratory of Quantum Optics at the University of Nova Gorica (UNG) and by that of the Microanalytical Centre at Jožef Stefan Institute (JSI). In particular, the UNG team will be responsible for the preparation of the photon (HHG and FEL) beams carrying OAM, while the JSI team will be in charge of the generation of an electron beam carrying OAM. The manipulation and characterisation of the beams carrying OAM will be carried out jointly by the two teams. Furthermore, both teams will be involved in the experimental and theoretical work needed to prepare and perform the experiments with the photon and electron beams. The HHG source CITIUS, whose construction was funded by the Cross-border Cooperation Programme Italy-Slovenia 2007-2013, is in operation at UNG and is already used in experiments conducted in collaboration between JSI and UNG. FEL light carrying OAM will be generated at the FERMI FEL in operation at the Sincrotrone Trieste laboratory (Italy), where the project leader is part of the team in charge of the source operation. As such, he has direct access to FEL beam time and will be able, together with UNG and JSI teams, to carry out the experiments proposed in the present project. Therefore, the already on-going experimental activities of the JSI team at the FERMI FEL will be further strengthened through the long-standing collaboration between UNG and Sincrotrone Trieste. The UNG-JSI partnership will benefit from the world-leading expertise of the JSI team in using electron and synchrotron sources and in theoretical modelling of light-matter interactions, while JSI will in turn take advantage of the consolidated experience of the UNG team in developing and running both HHG and FEL sources. Based on the above, we expect that the proposed project will deepen and further develop the long-term collaboration between UNG and JSI.
Significance for science
With the successful implementation of the plan we would demonstrate that it is possible to reliably generate XUV and electron vortex beams with the proposed methods. The experiments on atomic targets which we plan to implement represent the first key tests of the efficiency of the orbital angular momentum transfer to the atoms. These experiments are the first important step towards the development of new technological methods which exploit the orbital angular momentum of the beams, e.g., in microscopy, high-density data storage, high and low-temperature superconductors and free-space communications. Moreover, the proposed studies may have a strong technological impact as they might lead to the development of new techniques, allowing to characterize and tune the properties of important materials such as cuprates, manganites, and ruthenates. Moreover, applications can be envisaged using STED (stimulated emission depletion)-like microscopy technique for enhancing the imaging resolution in the EUV/X-ray region without the need to use fluorophores.
Significance for the country
The studies using light beams carrying orbital angular momentum represent one of the first opportunities for increasing the bandwidths of the existing optical infrastructure for high-bandwidth data transfer. This is of importance in regions with low population density, for which the specific price of optical infrastructure is one of the severe bottlenecks for technological and economic advancement.
Most important scientific results
Final report
Most important socioeconomically and culturally relevant results
Final report
