Laboratory of Ultrafast Spectroscopy LSU

Ultrafast spectroscopy with femtosecond laser and fs/ps X-ray pulses – Condensed-phase dynamics – Dynamics of Biomolecules – Photovoltaic Materials

Welcome to Laboratory of Ultrafast Spectroscopy LSU

The activities of our laboratory aim at a detailed description of photo-induced processes in the molecular condensed phase (liquid, solid and proteins) and in metallic and semiconductor nanostructured materials. A central approach of our group is the visualization in "real time" of the processes by means of ultrafast laser spectroscopy.
The physical phenomena we investigate include: structural changes in the chromophores and the medium (be it a solvent or a protein) and the influence of local electric fields on their spectral and dynamical features. We also study the ultrafast dynamics of charge carriers in semiconductor and metallic nanostructures of different shapes and sizes.
The experimental tools we use are ultrafast picosecond and femtosecond transient absorption spectroscopy, ultrafast fluorescence up-conversion spectroscopy, photon-echo spectroscopy. We have also developed novel optical laser pump-X-ray probe techniques using femtosecond and femtosecond hard X-ray pulses from a synchrotron.

NEWS 

June 2019

Congratulations to Giulia Mancini for winning the VIDI grant at the Zernike Institute for Advanced Materials (RUG, NE)

May 2019

We published in collaboration with the University of Zürich a time-resolved 2DUV and CD study on Peptide dynamics:

"Broad-Band Ultraviolet CD Spectroscopy of Ultrafast Peptide Backbone Conformational Dynamics"

J. Phys. Chem. Lett., 2019, 10, pp 2700–2705

April 2019

We published a collaborative study on black phosporus:

"Photocarrier-induced band-gap renormalization and ultrafast charge dynamics in black phosphorus"

2D MaterialsVol 6, 3 (2019) DOI.org/10.1088/2053-1583/ab1216

March 2019

Our traditional winter seminar took place in Valtournenche (Italy) with many interesting talks.

Welcome to Anna Maron who visits our group for four months.

February 2019

The LACUS day took place on the 28th of february.

Thesis

Congratulation to Dr. Tania Palmieri for her public thesis defense!

Deep-ultraviolet

Majed Chergui published an invited perspective article on "Ultrafast molecular photophysics in the deep-ultraviolet" highlighted as editors pick:

J. Chem. Phys. 150, 070901 (2019) DOI.org/10.1063/1.5082644

January 2019

We published our work on time resolved circular dichroism in the UV in Optica highlighted on the EPFL news and the Physics World news:

Malte Oppermann, Benjamin Bauer, Thomas Rossi, Francesco Zinna, Jan Helbing, Jérôme Lacour, and Majed Chergui
"Ultrafast broadband circular dichroism in the deep ultraviolet"

Optica Vol. 6, Issue 1 ,pp. 56-60(2019) DOI: 10.1364/OPTICA.6.000056

x-ray

New study about x-ray transient grating spectroscopy got published in optics letters:

Opt. Lett. Vol. 44, Issue 3, pp. 574-577 (2019) DOI.org/10.1364/OL.44.000574

Up-conversion

We published our work on Fluorescence Up-conversion on Metalloporphyrins:
Olivier BrämAndrea Cannizzo, and Majed Chergui 

J. Phys. Chem. A 2019, 12371461-1468 DOI10.1021/acs.jpca.9b00007

December 2018

Congratulation to Dr. Thomas Rossi for the public thesis defense!

November 2018

The "International Symposium on Ultrafast Science: From the infrared to the X-rays" organised by Majed Chergui took place from November 28-30 in Lausanne.

Informations can be found at the event page as well as a gallery.

October 2018

Majed Chergui has been elected Fellow of the American Crystallographic Association:

https://www.amercrystalassn.org/fellowshttps://actu.epfl.ch/news/majed-chergui-fellow-of-the-american-crystallograp/

July 2018

New article on TiO2 pulblished in Nanoletters! Read the SB press and the highlight on phys.org:

Edoardo Baldini, Tania Palmieri, Adriel Dominiguez,  Pascal Ruello, Angel Rubio, Majed Chergui.

"Phonon-Driven Selective Modulation of Exciton   Oscillator Strengths in Anatase TiO2 Nanoparticles"

 Nano Lett. 2018, 1885007-5014
DOI: 10.1021/acs.nanolett.8b01837

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Benjamin Bauer, Tania Palmieri and Thomas Rossi presented their research as oral talks at the Ultrafast Phenomena 2018 Conference in Hamburg. Congratulations!

June 2018

Our study on diplatinum complexes is now published in PNAS:

Roberto Monni, Gloria Capano, Gerald Auböck, Harry B. Gray, Antonín Vlcek, Ivano Tavernelli, Majed Chergui.

"Vibrational coherence transfer in the ultrafast intersystem crossing of a di-platinum complex in solution."

 PNAS 25 June 2018. DOI: 10.1073/pnas.1719899115

SB news

New publication in PRL, also highlighted on the SB news:

Simon P. Neville, Majed Chergui, Albert Stolow, Michael S. Schuurman.

"Ultrafast X-ray spectroscopy of conical intersections"

 Physical Review Letters 120, 12 June 2018.

April 2018

The PhD Thesis of former student Edoardo Baldini "Nonequilibrium Dynamics of Collective Excitations in Quantum Materials" is now published as a book by Springer Nature. The book is part of the series "Springer Theses - The best of the best" for outstanding research in the Natural Sciences!

Welcome to LSU to the new postdoc Jeremy Rouxel and the master student Kevin Jablonka!

February 2018

Our X-ray study of hole trapping in ZnO is published in Nature Communication!
Read the press on SB news:

Thomas J. Penfold, Jakub Szlachetko, Fabio G. Santomauro, Alexander Britz, Wojciech Gawelda, Gilles Doumy, Anne Marie March, Stephen H. Southworth, Jochen Rittmann, Rafael Abela, Majed Chergui & Christopher J. Milne.
"Revealing hole trapping in zinc oxide nanoparticles by time-resolved X-ray spectroscopy"
Nature Communications 02 February 2018.

 

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Majed Chergui has been elected Foreign Member of the Royal Spanish Academy of Sciences (Real Academia de Ciencias). The achievement is highlighted in the EPFL SB news.

January 2018

In TiO2, electron cooling in the conduction band occurs in less than 50 fs!
Read our new article published on ACS Photonicsand highlighted on EPFL SB news:

Edoardo Baldini, Tania Palmieri, Enrico Pomarico, Gerald Auböck, and Majed Chergui

"Clocking the Ultrafast Electron Cooling in Anatase Titanium Dioxide Nanoparticles."

ACS Photonics 11th January 2018.

LASERLAB Forum

The 24th issue of the Laserlab Newsletter "LASERLAB Forum" is published featuring an article by Edoardo Baldini and Majed Chergui (LSU) on the absorption of light by titanium dioxide.

2018 - Fellow American Crystallographic Association

Majed Chergui has been elected Fellow of the American Crystallographic Association:

https://www.amercrystalassn.org/fellows

https://actu.epfl.ch/news/majed-chergui-fellow-of-the-american-crystallograp/

Past events