Forthcoming Events

01.10.2020 - 01.10.2020, AkademieHotel, Karlsruhe, Germany
26.10.2020 - 28.10.2020, Paul Scherrer Institut (PSI), Villigen,Switzerland

News

New scientific highlights- by MUST PIs Chergui, Milne and Wörner
New scientific highlights- from MUST researchers at PSI
Promotion to full professorcongratulations to Steve Johnson!
The Laser at 60: Ursula KellerOPN interviewed OSA Fellows
Former EPFL PhD student Edoardo Baldini wins the 2020 ACS PHYS Division Young Investigator Awards
New scientific highlights- by MUST PIs Banerji, Chergui and Wolf
Prix de l'innovation AGROVINA 2020- for Agrolase: detecting spores of pathogens in real time
Ruth Signorell receives the Humboldt Prize- awarded in recognition of outstanding achievements in research and teaching

Energy relaxation pathways between light-matter states revealed by coherent two-dimensional spectroscopy

September 11, 2020

When a molecule is embedded inside a nanocavity and under certain conditions, new hybrid matter-light states appear, called polaritons. They result from the energy exchange between the optical field inside the nanocavity and the embedded molecules, similar to two coupled pendula exchanging energy.

This leads to changes in the optical properties of the resonator-molecule system. By engineering the properties of the optical field via the nanocavity design, and the way light couples to it, the properties and behavior of “polaritonic systems” can be modified at will and in a systematic fashion.

The energy flow between polaritonic states is crucial to understand for a wide range of applications. In a new article published in Communications Physics, the lab of Majed Chergui at EPFL within the Lausanne Centre for Ultrafast Science, in collaboration with the group of Karl Börjesson at the University of Gothenburg, has managed to gain unique new insights into the energy flow between light-matter states that are created when molecular excitations are coupled to an optical field.

The international team shows how excitation into the energetically higher-lying polaritonic state leads to population of the lowest within tens of femtoseconds. To achieve these results, the authors used state-of-the-art visible multidimensional spectroscopy (an optical domain analogue of nuclear magnetic resonance spectroscopy), which allows to overcome the typically encountered uncertainty between time and energy resolution in spectroscopy and is uniquely suited to study these light-matter interactions. These results demonstrate the ability to engineer light-matter states at will and to control the way energy flows in them. The team’s novel results are deemed to stimulate future experiments on similar systems and contribute to the development of novel applications.


Using state-of-the-art laser spectroscopy, researchers at EPFL and the University of Gothenburg have found how energy flows in real-time among hybrid light-matter states, providing unique insight into the dynamics of these states. The work will help develop novel applications that can use light to tailor-make properties of a material.

See also: EPFL News,
 
Reference: Mewes, L., Wang, M., Ingle, R.A., Börjesson, K., and Chergui, M. (2020). Energy relaxation pathways between light-matter states revealed by coherent two-dimensional spectroscopy. Commun Phys 3, 157 (10.1038/s42005-020-00424-z)

<<
NCCR MUST Office : ETHZ IQE/ULP-HPT H3 | Auguste-Piccard-Hof 1 | 8093 Zurich | E-Mail | +41 44 633 36 02
The National Centres of Competence in Research (NCCR) are a research instrument of the Swiss National Science Foundation
FNSNF