Publications by Thomas Charles Henry Rossi

Disentangling Thermal from Electronic Contributions in the Spectral Response of Photoexcited Perovskite Materials

Majed Chergui, Thomas Charles Henry Rossi, Lijie Wang, Malte Oppermann

Disentangling electronic and thermal effects in photoexcited perovskite materials is crucial for photovoltaic and optoelectronic applications but remains a challenge due to their intertwined nature in both the time and energy domains. In this study, we emp ...

Amer Chemical Soc2024

Disentangling the evolution of electrons and holes in photoexcited ZnO nanoparticles

Majed Chergui, Natalia Nagornova, Thomas Charles Henry Rossi, Hui-Yuan Chen

The evolution of charge carriers in photoexcited room temperature ZnO nanoparticles in solution is investigated using ultrafast ultraviolet photoluminescence spectroscopy, ultrafast Zn K-edge absorption spectroscopy, and ab initio molecular dynamics (MD) s ...

Aip Publishing2023

Quantifying Photoinduced Polaronic Distortions in Inorganic Lead Halide Perovskite Nanocrystals

Majed Chergui, Giulia Fulvia Mancini, Andre Al Haddad, Thomas Charles Henry Rossi, Nicola Colonna, Dominik Kinschel, James Michael Budarz, Oliviero Cannelli, Michele Puppin, Ludmila Maria Diniz Leroy

The development of next-generation perovskite-based optoelectronic devices relies critically on the understanding of the interaction between charge carriers and the polar lattice in out-of-equilibrium conditions. While it has become increasingly evident fo ...

2021

X-ray absorption linear dichroism at the Ti K-edge of rutile (001) TiO2 single crystal

Majed Chergui, Giulia Fulvia Mancini, Thomas Charles Henry Rossi, Dominik Kinschel, Oliviero Cannelli, Camila Bacellar Cases Da Silveira, Jérémy Raymond Jean Maurice Rouxel

X-ray absorption linear dichroism of rutile TiO2 at the Ti K-edge provides information about the electronic states involved in the pre-edge transitions. Here, linear dichroism with high energy resolution is analyzed in combination with ab initio finite dif ...

INT UNION CRYSTALLOGRAPHY2020

Slow Charge Carrier Relaxation in Gold Nanoparticles

Majed Chergui, Lars-Hendrik Mewes, Thomas Charles Henry Rossi, Lijie Wang, Malte Oppermann, Benjamin Bauer, Davood Zare

We report on ultrafast transient absorption (TA) studies of surface plasmon-excited similar to 25 nm-diameter Au nanoparticles in solution, monitoring the response of the surface plasmon resonance in the visible region (1.7-3.0 eV) and that of the inter- a ...

AMER CHEMICAL SOC2020

Cooling dynamics of electrons in MAPbBr(3) probed in the deep-UV

Majed Chergui, Peter Chen, Thomas Charles Henry Rossi, Lijie Wang, Malte Oppermann, Yu-Hsien Chiang

Transient absorption in the Visible and in the deep-UV is performed on MAPbBr(3) thin films with 3.1 eV pump excitation. The UV probe can access higher order transitions in the material exploring different high-symmetry points of the Brillouin zone. Uncorr ...

E D P SCIENCES2019

Intracellular bacteria engage a STING-TBK1-MVB12b pathway to enable paracrine cGAS-STING signalling

Alix Martin, Thomas Charles Henry Rossi, Ensieh Farahani, Andrea Ablasser, Bing Zhang

The innate immune system is crucial for eventual control of infections, but may also contribute to pathology. Listeria monocytogenes is an intracellular Gram-positive bacteria and a major cause of food-borne disease. However, important knowledge on the int ...

NATURE PUBLISHING GROUP2019

X-ray absorption linear dichroism at the Ti K edge of anatase TiO2 single crystals

Majed Chergui, Giulia Fulvia Mancini, Thomas Charles Henry Rossi, Dominik Kinschel, Oliviero Cannelli, Camila Bacellar Cases Da Silveira, Jérémy Raymond Jean Maurice Rouxel

Anatase TiO2 (a-TiO2) exhibits a strong x-ray absorption linear dichroism in the pre-edge, the XANES and the EXAFS at the titanium K edge. In the pre-edge region, the behavior of the A1-A3 and B peaks originating from the 1s - 3d transitions is due to the ...

2019

Ultrafast broadband circular dichroism in the deep ultraviolet

Majed Chergui, Jérôme Lacour, Thomas Charles Henry Rossi, Malte Oppermann, Benjamin Bauer

The measurement of chirality and its temporal evolution are crucial for the understanding of a large range of biological functions and chemical reactions. Steady-state circular dichroism (CD) is a standard analytical tool for measuring chirality in chemist ...

OPTICAL SOC AMER2019

Phonon-Driven Selective Modulation of Exciton Oscillator Strengths in Anatase TiO2Nanoparticles

Majed Chergui, Gerald Auböck, Thomas Charles Henry Rossi, Tania Palmieri, Edoardo Baldini, Enrico Pomarico, Malte Oppermann

The way nuclear motion affects electronic responses has become a very hot topic in materials science. Coherent acoustic phonons can dynamically modify optical, magnetic, and mechanical properties at ultrasonic frequencies, with promising applications as se ...

American Chemical Society (ACS)2018

Charge-carrier Dynamics in Metal Oxides and Hybrid Lead Perovskites investigated by Time-Resolved UV and X-ray Spectroscopy

Thomas Charles Henry Rossi

In modern ultrafast optoelectronic technologies based on wide band gap insulators, the non-equilibrium dynamics of photogenerated charges plays a major role. Unravelling the mechanisms of interaction between these charge carriers and their environment is c ...

EPFL2018

Localized holes and delocalized electrons in photoexcited inorganic perovskites: Watching each atomic actor by picosecond X-ray absorption spectroscopy

Majed Chergui, Andre Al Haddad, Lars-Hendrik Mewes, Thomas Charles Henry Rossi, Gloria Capano, Jakob Grilj, Fabio Giacomo Santomauro, Dominik Kinschel, James Michael Budarz

We report on an element-selective study of the fate of charge carriers in photoexcited inorganic CsPbBr3 and CsPb(ClBr)(3) perovskite nanocrystals in toluene solutions using time-resolved X-ray absorption spectroscopy with 80 ps time resolution. Probing th ...

Amer Inst Physics2017

Time-resolved Element-selective Probing of Charge Carriers in Solar Materials

Majed Chergui, Mercedes Hannelore Rittmann-Frank, Jochen Rittmann, Thomas Charles Henry Rossi, Fabio Giacomo Santomauro, Dominik Kinschel, James Michael Budarz

We review our recent results on the implementation of picosecond (ps) X-ray absorption spectroscopy to probe the electronic and geometric structure of centres formed by photoexcitation of solar materials such as TiO2 polymorphs and inorganic Cs-based perov ...

2017

The LOUVRE Laboratory: State-of-the-Art Ultrafast Ultraviolet Spectroscopies for Molecular and Materials Science

Majed Chergui, Frank van Mourik, Natalia Nagornova, Lars-Hendrik Mewes, Thomas Charles Henry Rossi, Tania Palmieri, Edoardo Baldini, Malte Oppermann, Benjamin Bauer, Aurelio Oriana

We describe the facilities for ultraviolet studies in the femtosecond to nanosecond time domain. These facilities consist of: i) a set-up for deep-ultraviolet spectroscopy in the 260–380 nm range in both pump and probe pulses for transient absorption/refle ...

2017

Interfacial Electron Injection Probed by a Substrate-Specific Excitonic Signature

Majed Chergui, Gerald Auböck, Thomas Charles Henry Rossi, Tania Palmieri, Edoardo Baldini, Enrico Pomarico, Malte Oppermann

Ultrafast interfacial electron transfer in sensitized solar cells has mostly been probed by visible-to-terahertz radiation, which is sensitive to the free carriers in the conduction band of the semiconductor substrate. Here, we demonstrate the use of deep- ...

2017

Characterizing the Structure and Defect Concentration of ZnO Nanoparticles in a Colloidal Solution

Majed Chergui, Camelia Borca, Marco Eli Reinhard, Mercedes Hannelore Rittmann-Frank, Thomas James Penfold, Jochen Rittmann, Thomas Charles Henry Rossi

The structure and defect concentration of colloidal solutions of ZnO nanoparticles, synthesized by a sol gel procedure (SG-NP), as well as commercially available ZnO nanoparticles (SA-NP) are investigated by UV-vis absorption spectroscopy, transmission ele ...

Amer Chemical Soc2014