Projects / Programmes
Structured light as a tool for triggering and probing new states of matter
| Code |
Science |
Field |
Subfield |
| 1.02.00 |
Natural sciences and mathematics |
Physics |
|
| Code |
Science |
Field |
| 1.03 |
Natural Sciences |
Physical sciences |
Structured light, orbital angular momentum, high-order harmonic generation, free electron laser, dichroism, nanometer spatial scale, femtosecond temporal scale.
Data for the last 5 years (citations for the last 10 years) on
April 25, 2024;
A3 for period
2018-2022
Data for ARIS tenders (
04.04.2019 – Programme tender,
archive
)
| Database |
Linked records |
Citations |
Pure citations |
Average pure citations |
| WoS |
287 |
7,118 |
6,231 |
21.71 |
| Scopus |
303 |
8,199 |
7,268 |
23.99 |
Researchers (8)
Organisations (2)
Abstract
Probing the microscopic properties of matter through interaction with photons or other particles provides invaluable data used in a wide range of scientific disciplines, e.g., in chemistry, biology, or physics, and in various technological fields. Photons can impart energy, linear momentum, as well as spin and orbital angular momentum to atoms when they pass through matter. While the spin angular momentum (SAM) of a beam is associated with its polarization, the orbital angular momentum (OAM) depends on the spatial profile of the beam. For example, beams whose wavefronts are helically shaped carry a well-defined OAM along the beam's propagation direction. A design and implementation of even the most basic experiments with optical vortex beams is a challenging task. The primary reasons for this can be attributed to the fact that an efficient transfer of the OAM to atoms is hindered by the zero intensity on the beam axis and that the transfer is strongly dependent on the displacement of atoms from the beam centre. Indeed, the atomic wave function is extremely localized on the scale of the OAM beam’s waist. Off-axis atoms experience the light field as an ordinary Gaussian beam and atoms close to the optical axis, where the OAM is well defined, experience a vanishingly small field. Besides, the fraction of near-axis atoms is small. Although the transfer of optical OAM to photoelectrons seems unlikely, if it happens, it should involve a new type of non-dipole transition related to the OAM-carrying vector potential, which could be used, for example, to optically induce orbital magnetization in molecules. In the past, photon beams carrying OAM have been generated in the visible range. In a recent project financed by ARRS (no. J1–8134), we proposed: a) to demonstrate effective schemes, allowing to produce ultra-short vortex beams in x-ray and extreme ultraviolet (XUV) spectral ranges using high harmonic generation (HHG) in gases and free-electron lasers (FELs); b) to perform a first set of proof-of-principle experiments aimed at demonstrating the possibility to transfer light OAM to atomic targets. The project was quite successful. With the present project, we intend to take advantage of the unique properties of the sources we have set up and move from first demonstrative experiments to the establishment of new OAM-based techniques for the generation, control and diagnostics of new states of matter. The main scientific goals of the project are summarised here below: 1) We propose to establish a new method for generating steady-state, magnetic field pulses with duration tunable from femto- to nanoseconds, localized at a nanometer scale. 2) We propose to establish a new method based on OAM diffraction as a tool for topological reconstruction of nano-structures and for time-resolved magnetic helicoidal dichroism. 3) As a fundamental question related to the above, we plan to further investigate the laws determining the transfer of OAM to atoms. To achieve these goals, we will take advantage of the long-standing expertise of the teams of the university of Nova Gorica and of Jožef Stefan Institute. The collaboration will strongly benefit from the support of the theory group of the university of Halle, of two groups of CEA Paris and the university of Cergy, and of the groups operating the Fermi FEL at laboratory Elettra Sincrotrone Trieste. The experimental activities will be carried out at the university of Nova Gorica, at the JSI, at the Jožef Stefan Institute and at the FERMI FEL.
