The Photonic Materials and Devices–Laboratory (PMDL) is an Applied Physics research group, oriented in the field of Photonics. PMDL started its activities in March 2004. The PMDL focuses on the research of materials, light propagation effects, designs and fabrication methods for the development of Photonic Devices mainly in guided wave geometry, with significant effort currently being invested in grating based and Photonic Crystal Fibre (PCF) devices. The knowledge generated on materials related problems and processes, as well as, light propagation effects is directly transferred into the research for developing photonic devices of increased technological and scientific added value, targeting high socio-economical impact applications. The strategic vision of the group refers to the development of hybrid photonic devices and related processes by engaging existing and emerging technologies in a ‘disruptive’ way, covering scientific and technology readiness levels from the basic research and the proof-of-principle study, up to the laboratory prototyping.

The objectives of PMDL can be summarized into the following:

• Fusion of diverse optical design and material technologies for the demonstration of “disruptive” photonic devices, well beyond the state-of-the-art
• Photonic research for meeting Societal and Market needs, spanning from “proof-of-principle-studies” up to “laboratory-prototype-systems”
• Investigation of fundamental light propagation effects and implementation of those into realistic photonic device designs
• New laser processing methods for accelerating development of photonic devices

Research Topics

Research directions / Objectives

The research targets the understanding the formation mechanisms, the stability, the structure (geometric and/or electronic) and the properties (optical activity, chemical reactivity, catalytic activity) of clusters and free biomolecules and also to study nanostructured materials made out of clusters.

Our efforts in obtaining information about the stability and structure of free clusters and biomolecules with photofragmentation  experiments of mass selected clusters, is recently focused in a new experimental technique that we proposed and presented in a series of papers and relies on crossed  molecular beam scattering. This method is significantly faster and more efficient for obtaining fragmentation cross sections, without mass selection of the individual clusters.

Recently, we apply our know-how from the basic research studies for investigations in several applied fields such as:

Mass spectroscopy in combination with laser induced break down spectroscopy (LIBS). Such combined studies are applied for the analysis of the composition and structure of (in collaboration with Prof. D. Anglos). Second Poster Award to Olga Kokkinaki, M. Velegrakis, D. Anglos and C. Mihesan for the presentation of their poster “Combined laser induced breakdown spectroscopy and mass spectrometry for the analysis of cultural heritage materials” in “TECHNART 2011” (Non-destructive and Microanalytical Techniques in art and cultural Heritage) which was held in Berlin, April 26-29, 2011.

•      Nanostructured materials produced by laser ablation in liquids in conjugation with biomolecules. The object of is the formation of metallic or metal oxide bionanoconjugates (BNC’s). . This project is performed in collaboration with Centre of Advanced Research in Nanobioconjugates and Biopolymers, Iasi, Romania and a postdoc (C. Mihesan) is supported from Romanian National Authority for Scientific Research, CNCS – UEFISCDI, project number PN-II-RU-TE-2011-3-0174. We have already achieved the synthesis of magnetic iron oxide particles coated with a hydrophilic shell of citric acid, by a one-step technique based on laser ablation in liquid. A presentation and a paper are submitted for publication.
•       Recently we apply Uv-Vis and fluorescence spectroscopy to analyze wines by monitoring the spectroscopic fingerprints through the entire manufacturing process from grapes to the final product. This project is performed within the framework of a “Thales” program in cooperation with other laboratories of the University of Crete (NMR, GC-MS) and the Technological Educational Institute of Crete (FTIR). In this activity three young scientist are employed: A. Philippidis (postdoc), M. Poulakis (PhD) and A. Papadaki (MSc).

The Dynamics lab at IESL-FORTH uses light (especially lasers) to study Chemistry. Current projects are briefly discussed below.

Research Topics

High-energy Photodissociation Dynamics of small molecules

We have investigated the dynamics of HBr, CH₃Br and CH₃I when excited in the 7-10 eV region. The interactions between Rydberg, ion pair and ionic states of the molecules affect the photoproducts significantly. For example, while excitation energy in CH3Br is distributed in electronic and ro-vibrational excitation of the CH₃ fragment, in CH₃I all excitation energy is channeled into electronic excitation of the I fragment.
Our CH3I work was featured as a PCCP 2020 Hot Article and Editor’s choice in 2020.

Photoelectron Circular Dichroism of chiral molecules

We published the first tunable ns PECD data using a tunable ns laser to ionize fenchone enantiomers in the 375-420 nm region in order to see if PECD changes with vibrational level excitation. Our data suggest that is doesn’t, but further investigation in different regions and molecules is needed to confirm. 

Velocity Resolved Kinetics

The aim is to characterize the important factors that influence the kinetics of elementary reactions at surfaces, e.g. the chemical nature of the catalyst and the geometry of the active site (stereodynamics). We chose elementary reactions involving C, H, O, N, as these are important in many key industries, such as the methane reforming, syngas, fuel cells, Fischer-Tropsch synthesis and the Haber-Bosch process.  Our strategy is that of a “bottom-up” approach to catalysis, i.e., building and understanding complex heterogeneous chemical catalysis, from the site-specific kinetics of the elementary building block reactions.  Our measurements, will serve for benchmarking first principles calculations of reaction rates in surface chemistry.  Our methodology measures the kinetics in the ms regime with temperatures in the 200 to 1000 K range, i.e, conditions more relevant to industrial conditions.

Structural Dynamics of molecules probed with Electron Diffraction

Our Time-Resolved Electron Diffractometer is currently under construction. We use the term “time-resolved” and not "ultrafast" as we plan to use both ultrashort (500fs) and nanosecond laser pulses, in order to investigate phenomena ranging from a few ps to μs. We envision first experiments in “dark” reactions in gas phase with a plan to expand in solid state studies as soon as technically possible.

Spectroscopic detection of (fossil) fuels adulteration

We combine machine learning analysis methods and spectroscopic data ( UV-NIR absorption, fluorescence, FT-IR) of pure fossil fuels (different types of gasoline and diesel) and adulterants (solvents, lubricants, lubricants waste oils) and their mixtures aiming to develop a system that will detect fuel adulteration spectroscopically in a reliable, cheap and user-friendly fashion. The work is funded under project "APOFASH".
This work is part of a general research direction aiming to improve how we use light and spectroscopy to detect molecules of choice in a chemical mixture.

Research directions / Objectives

 Mission Statement

To explore the unprecedented potential of matter-wave interferometry

To look at (de)coherence in increasingly complex quantum systems.

 The three experiments:

 BEC 1: Coherently guided matter-wave interferometry. Our matter-waves will be made from Bose-Einstein Condensates (BEC). The interferometer will consist of a novel magnetic ring-shaped waveguide based on time-averaged adiabatic potentials (TAAP). A little 'teaser' movie of our TAAP can be seen here. With this experiment we are part of the Marie Curie Initial Training Network QTea (395k€), where we are developing the next generation of guided matter-wave interferometers. We are also the coordinators of the MatterWave network (a FET-STREP 2013-2017 network by the EU Total 2.6M€ of which IESL will get 652k€).

 BEC 2: Atom Lasers and BEC at high atom numbers. We have set up a second experiment, which looks at BEC at higher atom numbers. Here, we have recently demonstrated a novel atom laser, which has a record flux of 4x10^7 atom/s. We also made the coldest thermal source to date (200nK). We are currently exploring the phase properties of atom lasers.

In the future we plan to study the kinetics of the condensation process itself, as well as the rise and fall of coherence in phase-fluctuating condensates.

 BEC in space: Testing the equivalence principle. We are the coordinators of the Greek contribution to the STE-QUEST mission to send a BEC into space. The idea of the mission is to test Einstein’s equivalence principle, which states that the mass of acceleration and attraction are the same. Our part will be to design and construct the optical switching board at the center of the mission. The mission is a pan-European effort lead by Prof. Rasel from Hannover.

HIGHLIGHTS

Awards and Prizes

2005: ‘Certificate of Excellence‘
 of the
Young Scholars Competition, University of Berkeley
2006: Marie-Curie Excellence Grant  (MatterWaves)

Scientific Highlights

2009 The first Bose-Einstein Condensate of South-Eastern Europe
2013 By one order of magnitude the brightest atom laser ever

LATEST PAPERS

Saurabh Pandey, Hector Mas, Georgios Vasilakis, and Wolf von Klitzing
Atomtronic Matter-Wave Lensing
Physical Review Letters  126:17  (2021)  https://doi.org/10.1103/physrevlett.126.170402

Saurabh Pandey, Hèctor Mas, Giannis Drougakis, Premjith Thekkeppatt, Vasiliki Bolpasi, Georgios Vasilakis, Konstantinos Poulios, and Wolf von Klitzing
Hypersonic Bose--Einstein condensates in accelerator rings
Nature  570:7760 205--209 (2019) https://doi.org/10.1038/s41586-019-1273-5

Research Topics

BEC - Infrastructure

RESEARCH DIRECTIONS / OBJECTIVES

 Mission Statement

To explore the unprecedented potential of matter-wave interferometry

To look at (de)coherence in increasingly complex quantum systems.

 The three experiments:

 BEC 1: Coherently guided matter-wave interferometry. Our matter-waves will be made from Bose-Einstein Condensates (BEC). The interferometer will consist of a novel magnetic ring-shaped waveguide based on time-averaged adiabatic potentials (TAAP). A little 'teaser' movie of our TAAP can be seen here. With this experiment we are part of the Marie Curie Initial Training Network QTea (395k€), where we are developing the next generation of guided matter-wave interferometers. We are also the coordinators of the MatterWave network (a FET-STREP 2013-2017 network by the EU Total 2.6M€ of which IESL will get 652k€).

 BEC 2: Atom Lasers and BEC at high atom numbers. We have set up a second experiment, which looks at BEC at higher atom numbers. Here, we have recently demonstrated a novel atom laser, which has a record flux of 4x10^7 atom/s. We also made the coldest thermal source to date (200nK). We are currently exploring the phase properties of atom lasers.

In the future we plan to study the kinetics of the condensation process itself, as well as the rise and fall of coherence in phase-fluctuating condensates.

 BEC in space: Testing the equivalence principle. We are the coordinators of the Greek contribution to the STE-QUEST mission to send a BEC into space. The idea of the mission is to test Einstein’s equivalence principle, which states that the mass of acceleration and attraction are the same. Our part will be to design and construct the optical switching board at the center of the mission. The mission is a pan-European effort lead by Prof. Rasel from Hannover.

 

HIGHLIGHTS

Publication
2019: Nature Publications: Hypersonic Transport of Bose-Einstein Condensates in a Neutral-Atom Accelerator Ring (https://doi.org/10.1038/s41586-019-1273-5)
Awards and Prizes
2005: ‘Certificate of Excellence‘
 of the
Young Scholars Competition, University of Berkeley
2006: Marie-Curie Excellence Grant  (MatterWaves)

Scientific Highlights
2009 The first Bose-Einstein Condensate of South-Eastern Europe
2013 By one order of magnitude the brightest atom laser ever

 

 

Research directions / Objectives

1.       Development of cavity-enhanced polarimetry (for improvement of sensitivity and time resolution).
2.       Development of cavity-enhanced ellipsometry (for improvement of sensitivity and time resolution).
3.       Measurement of atomic parity-nonconservation in Iodine, Xenon, and Mercury.
4.       Production of spin-polarized atoms and molecules. 

HIGHLIGHTS

•  European Research Council (ERC) Starting Grant (2008-2013), “Time-resolved Ring-Cavity-Enhanced Polarization Spectroscopy (TRICEPS)”.
•  J. Chem. Phys. 132, 224310 (on photofragment polarization from polyatomic molecules) highlighted as one of 80 papers for the 80th anniversary of JCP: http://imageserve.chem.unc.edu/resources/pdf_files/home_page/JCP_80th_Anniversary.pdf Proposal for cavity-enhanced parity-nonconserving (PNC) optical rotation in Hg, Xe, and I [Phys. Rev. Lett. 108, 210801 (2012), Editor Suggestion].

· Demonstration of new cavity-enhanced polarimetry techniques:

       a) Cavity Ring-Down Ellipsometry (CRDE) [J. Chem. Phys. 31, 121101 (2009)].

       b) Evanescent-Wave Cavity Ring-Down Ellipsometry (EW-CRDE) [US patent pending].

       c) Chiral-Cavity Ring-Down (CCRD) [Phys. Rev. Lett. 108, 210801 (2012), patent pending].

· First measurement of the complete three-dimensional steric effect in a bimolecular chemical reaction (dependence of reactivity on approach geometry) [F. Wang, K. Liu, T.P. Rakitzis, Nature Chemistry 4, 636 (2012)].

· Proposal and demonstration for the pulsed-laser production of spin-polarized atoms and molecules by the time-dependent transfer of polarization from molecular rotational polarization via the hyperfine interaction [T.P. Rakitzis,Phys. Rev. Lett. 94, 83005 (2005)].

· First observation of the photofragment recoil deflection angle, from the photodissociation of OCS molecules three-dimensionally “fixed-in-space” [Rakitzis et al., Science  303, 1852 (2004)].

•  Production of spin-polarized hydrogen atoms from pulsed molecular photodissociation at high density [Rakitzis et al., Science  300, 1936 (2003)], and pulsed laser-detection.

Research Topics

In the UNIS group we are working in the field of intense ultrashort laser pulse interaction with matter. Our activities are grouped in 3 directions.

We study the nonlinear propagation of intense ultrashort laser pulses in transparent media and related filamentation processes. We develop experimental tools to monitor the interaction of the strong laser fields with the matter and also ways to control the nonlinear propagation through the use of "exotic" wavepackets or photonic lattices.

In the second direction we develop novel strong field THz sources. We are investigating mainly filamentation based approaches and explore novel ways for increasing the source peak power. We are proposing ways of taming the source properties through filamentation tailoring methods or using novel artificial materials like metamaterials and eutectics. With the available THz intensities we explore the new era of nonlinear THz optics.

Finally, in the third direction we use photonic lattices for a number of applications. From the control of the nonlinear propagation, to the study of complexity physics and quantum information and quantum analogs.

In our research we are dealing with both fundamental science aspects as well as technological applications. The polyvalent nature of our facility allows studies in cross-disciplinary science including physics, chemistry, materials science and bio-medicine.

HIGHLIGHTS

Awards

•  Rozhdestvensky honorary medal from the Russian Optical Society (2013) for Prof. Stelios Tzortzakis

•  Marie Curie Excellence Grant (~2M€ ; 2006-2010)  Prof. Stelios Tzortzakis

Research Highlights

• Demonstration of a sub-picosecond all-optical THz switch based on three-dimensional (3D) terahertz meta-atoms (link)

• Development of a novel THz source that exceeds in power performance and conversion efficiency any other THz source known to date (link)

• Crossing the threshold of ultrafast 3D laser writing in bulk silicon (link)

• Generation of highly efficient broadband terahertz pulses from ultrashort laser filamentation in liquids (link)

• Theoretical and experimental demonstration that the harmonics from abruptly autofocusing ring-Airy beams preserve the phase distribution of the fundamental beam. even after focusing these beams still spatially overlap, surprisingly over elongated focal volumes (link)

• Numerical and experimental demonstrations of the accelerating Airy and ring-Airy beams that show that the waves are a superposition of twin waves, which are conjugate to each other under inversion of the propagation direction, known as Janus Waves (link)

• Generation of THz waves that has more than 5 times the pulse energy of THz waves created with standard Gaussian beams, by using ring-Airy beams (link)

• Accessing Extreme Spatiotemporal Localization of High-Power Laser Radiation through Transformation Optics and Scalar Wave Equations (link)

• Demonstration that the focus position of abruptly autofocusing ring Airy beams can be tailored to cover an extended range, maintaining at the same time an almost invariant focal voxel (link)

•  First demonstration of nonlinear intense “light bullets” in normal dispersion media (link)

• First demonstrations of dynamical filamentation tailoring in various media and photonic lattices (link)

For more info, please don't hesitate to visit our group web page https://unis.iesl.forth.gr/