TY  - JOUR
A1  - Brixner, Tobias
A1  - Pawłowska, Monika
A1  - Goetz, Sebastian
A1  - Dreher, Christian
A1  - Wurdack, Matthias
A1  - Krauss, Enno
A1  - Razinskas, Gary
A1  - Geisler, Peter
A1  - Hecht, Bert
T1  - Shaping and spatiotemporal characterization of sub-10-fs pulses focused by a high-NA objective
N2  - We describe a setup consisting of a 4 f pulse shaper and a microscope with a high-NA objective lens and discuss the spects most relevant for an undistorted spatiotemporal profile of the focused beam. We demonstrate shaper-assisted pulse compression in focus to a sub-10-fs duration using phase-resolved interferometric spectral modulation (PRISM). We introduce a nanostructure-based method for sub-diffraction spatiotemporal characterization of strongly focused pulses. The distortions caused by optical aberrations and space–time coupling from the shaper can be reduced by careful setup design and alignment to about 10 nm in space and 1 fs in time.
KW  - Interference microscopy
KW  - Scanning microscopy
KW  - Subwavelength structures
KW  - nanostructures
KW  - Pulse shaping
KW  - Ultrafast measurements
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111120
ER  - 
TY  - JOUR
A1  - Wurdack, Matthias
A1  - Lundt, Nils
A1  - Klaas, Martin
A1  - Baumann, Vasilij
A1  - Kavokin, Alexey V.
A1  - Höfling, Sven
A1  - Schneider, Christian
T1  - Observation of hybrid Tamm-plasmon exciton-polaritons with GaAs quantum wells and a MoSe\(_{2}\) monolayer
JF  - Nature Communications
N2  - Strong light matter coupling between excitons and microcavity photons, as described in the framework of cavity quantum electrodynamics, leads to the hybridization of light and matter excitations. The regime of collective strong coupling arises, when various excitations from different host media are strongly coupled to the same optical resonance. This leads to a well-controllable admixture of various matter components in three hybrid polariton modes. Here, we study a cavity device with four embedded GaAs quantum wells hosting excitons that are spectrally matched to the A-valley exciton resonance of a MoSe\(_{2}\) monolayer. The formation of hybrid polariton modes is evidenced in momentum resolved photoluminescence and reflectivity studies. We describe the energy and k-vector distribution of exciton-polaritons along the hybrid modes by a thermodynamic model, which yields a very good agreement with the experiment.
KW  - two-dimensional materials
KW  - microresonators
KW  - nanophotonics and plasmonics
KW  - cavity device
KW  - strong coupling
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-170480
VL  - 8
IS  - 259
ER  - 
TY  - JOUR
A1  - Waldherr, Max
A1  - Lundt, Nils
A1  - Klaas, Martin
A1  - Betzold, Simon
A1  - Wurdack, Matthias
A1  - Baumann, Vasilij
A1  - Estrecho, Eliezer
A1  - Nalitov, Anton
A1  - Cherotchenko, Evgenia
A1  - Cai, Hui
A1  - Ostrovskaya, Elena A.
A1  - Kavokin, Alexey V.
A1  - Tongay, Sefaattin
A1  - Klembt, Sebastian
A1  - Höfling, Sven
A1  - Schneider, Christian
T1  - Observation of bosonic condensation in a hybrid monolayer MoSe2-GaAs microcavity
JF  - Nature Communications
N2  - Bosonic condensation belongs to the most intriguing phenomena in physics, and was mostly reserved for experiments with ultra-cold quantum gases. More recently, it became accessible in exciton-based solid-state systems at elevated temperatures. Here, we demonstrate bosonic condensation driven by excitons hosted in an atomically thin layer of MoSe2, strongly coupled to light in a solid-state resonator. The structure is operated in the regime of collective strong coupling between a Tamm-plasmon resonance, GaAs quantum well excitons, and two-dimensional excitons confined in the monolayer crystal. Polariton condensation in a monolayer crystal manifests by a superlinear increase of emission intensity from the hybrid polariton mode, its density-dependent blueshift, and a dramatic collapse of the emission linewidth, a hallmark of temporal coherence. Importantly, we observe a significant spin-polarization in the injected polariton condensate, a fingerprint for spin-valley locking in monolayer excitons. Our results pave the way towards highly nonlinear, coherent valleytronic devices and light sources.
KW  - polaritons
KW  - two-dimensional materials
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-233280
VL  - 9
ER  -