Together with the teams of Mercedeh Khajavikhan, Demetri Christodoulides and Patrick LiKamWa we showed how to create topological lasing modes in a laser cavity that steers light around an exceptional point. Congratulations to Alexander Schumer, who spent several months with our partner groups in the US and now serves as the first author of a joint paper in Science. See also the news highlight in Laser Focus World and the press release from TU Wien.
Category: Scientific publication
Three letters in a row
Three letters involving our group have just been published in the Physical Review. The topics range from atomic frequency combs, an invariance property of the Fisher information, to the optimal detection of targets in complex media. Many thanks go to our collaborators in France, India, Germany and in the Netherlands.
The indestructible light beam
Together with the team of Allard Mosk at Utrecht University, we published a paper in Nature Photonics in which we introduce the concept of “scattering-invariant modes”. These special light waves have the property that they produce the same light pattern in the far-field, irrespective of whether a strongly scattering medium is put in their way or not (see image on the left). Find out more about these indestructible beams of light in the news highlight on Physics World or in the freely available version of the article.
Optimal information about the invisible
Together with Dorian Bouchet and Allard Mosk from the Nanophotonics group at Utrecht University, we demonstrated how to shape the wave-front of a coherent laser beam such as to obtain with it the maximal possible information about a target hidden behind or inside a disordered medium. Our joint work was published in Nature Physics and is described in the following press release compiled by Florian Aigner from the press office at TU Wien (see also highlight in Physics World).
Adaptive control of quantum cascade random lasers
Together with the THz lab at TU Wien we show in a new Nature Communication that quantum cascade random lasers can be adaptively controlled by a suitably shaped infrared beam. Following a control strategy developed by Nicolas Bachelard, an initially multi-mode THz random laser is turned into a tunable single-mode source. Discussions of our work can be found at the Austrian Press Agency, Chemie.de and at Analytica News.
The return of the spin echo
Together with a team from the Walther Meißner Institute and TU Munich, we showed in a recent Letter that the conventional Hahn echo pulse sequence from electron spin resonance produces a train of periodic, self-stimulated echoes when the involved spins are strongly coupled to a resonator. See discussions of this work on ChemEurope and on the websites of the Austrian Press Agency and TU Munich.
New Optica paper on non-Hermitian invisibility
In a new paper with Kostas, Ivor and Andre, we demonstrate how a dielectric medium can be made invisible for certain incoming beams when a suitable spatial distribution of gain and loss is added to the medium’s permittivity. (See highlight in Optica top downloads.)
Broken symmetry in a microcavity laser
In a new paper with the group of Yun-Feng Xiao published today in Nature Communications we show how the non-linearity in a symmetric microcavity leads to the formation of lasing modes with a pronounced chirality that we can control dynamically and all-optically by the bias in the pump direction.
Optimal wave fields for micro-manipulation in complex scattering environments
A new paper with our collaborators in Nice and London just appeared in Nature Photonics and is highlighted in OSA Optics & Photonics News and in Pro-Physik. In this work we demonstrate how to design the optimal wave front to deliver the highest possible force or torque onto a target embedded in a complex environment (see illustration on the left for a wave field transferring a strong torque onto a square target).
Angular Memory Effect of Transmission Eigenchannels
A joint work with Hasan Yılmaz and the group of Hui Cao just appeared in Physical Review Letters. We show that high-transmission channels in disordered media have an increased range of the angular memory-effect.