Ort / Place
Physik Campus Riedberg, Max-von-Laue-Str. 1, 60438 Frankfurt
Großer Hörsaal, Raum 0.111

Zeit / Time
Mittwochs /Wednesday , 16.00 Uhr c.t.
 
     
                          

18.10.2017

Prof. Dr. Ronny Thomale
Julius-Maximilians-Universität Würzburg,Lehrstuhl Theoretische Physik I

Topolectrical circuits

First developed by Alessandro Volta and Felix Savary in the early 19th century, circuits consisting of resistor, inductor and capacitor (RLC) components are now omnipresent in modern technology. The behavior of an RLC circuit is governed by its circuit Laplacian, which is analogous to the Hamiltonian describing the energetics of a physical system. We show that “topolectrical” boundary resonances (TBRs) appear in the impedance read-out of a circuit whenever its Laplacian bandstructure resembles that of topological semimetals - materials with extensive degenerate edge modes known as Fermi arcs that also harbor enigmatic transport properties. Due to the versatility of electronic circuits, our topological semimetal construction can be generalized to topolectrical phases with any desired lattice symmetry, spatial dimension, and even quasiperiodicity. Topolectrical circuits establish a bridge between electrical engineering and topological states of matter, where the accessibility, scalability, and operability of electronics promises to synergize with the intricate boundary properties of topological phases.


25.10.2017 

 - fällt heute aus -cancellered today -


 

 01.11.2017

Prof. Dr. Thomas Baumert
Institut für Physik und CINSaT, Universität Kassel

Designer Photons for Tailored Ultrafast Laser Control of Matter

How do the building blocks of matter move after irradiation with very short and intense laser pulses and can this movement be controlled and made use of?
To address these questions, we illuminate matter with extremely short laser pulses in the femtosecond regime and watch the ultrafast dynamics with stroboscopic methods in slow motion (femtosecond spectroscopy). Using optical synthesizers, we shape the laser light in time and can thus control the ultrafast dynamics (ultra-fast laser control) by customizing the energy transfer.
The span of our investigation ranges from free electrons, atoms and molecules in the gas phase to dye molecules and colloidal quantum dots in solution, as well as excitation and removal (ablation) mechanisms in solids and organic tissue.
In this talk - after an introduction to femtosecond spectroscopy and ultrafast laser control - I will concentrate on our current experiments devoted to tailored laser control of matter: material processing on the nanometer scale, the creation and tomographic reconstruction of 3D designer electron wave packets in the continuum, chiral recognition in the gas phase and charge oscillation controlled molecular excitation serve as illustrative examples. ls.
Die Dozenten der Phyk 

Rückblick Physikalisches Kolloquium:
SS 2010, WS 2010/11, SS 2011, WS 2011/12, SS 2012, WS 2012/13, SS 2013, WS 2013/14, SS 2014, WS2014/15, SS2015, WS2015/16, SS2016, WS2016/17, SS 2017