CMSP - 2 seminars next week

[Cond.Matt. & Stat.Mech.Section]

INFORMAL SEMINAR on Chemical Physics



Wednesday, 20 November   -    4:30  p.m. 

 
 

Luigi Stasi Seminar Room,   ICTP Leonardo Building (1st floor)

 


Stephan W.H. EIJT  ( Delft University of Technology )

 

" Nanoscale structure, surfaces and vacancies in sustainable energy materials: Interplay between experimental and ab-initio approaches "

 
Abstract

 

In this presentation, our recent studies on future generation thin film solar cells and hydrogen energy materials will be highlighted. The presence of di-vacancies in hydrogenated amorphous silicon (a-Si:H) was observed by a set of complementary techniques. These defects play an important role in the instability of a-Si:H layers against light-soaking (Staebler-Wronski effect). Further, colloidal PbSe nanoparticles were investigated by positron annihilation spectroscopies and ab-initio calculations, shedding light on their surface composition and electronic structure. Finally, recent studies on the impact of nanoscale particle size, surface energies and the presence of vacancies on hydrogen storage materials and hydrogen sensors are discussed.





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SEMINAR on  Disorder and strong electron correlations

 

Thursday,  21 November -  11:30 a.m.

 

Luigi Stasi Seminar Room,  Leonardo Building - first floor

 

Iacopo CARUSOTTO   ( INO-CNR BEC Center and University of Trento )

 


"Quantum fluids of light"

 

Abstract



A few years after the first observation of Bose-Einstein condensation, quantum gases of photons in suitably designed photonic microstructures are establishing themselves as flexible and powerful platforms for the study of many-body physics in a completely novel context.

In this talk, I will start by reviewing the first experiments that have demonstrated superfluid hydrodynamics effects in dilute photon fluids.

When a localized defect is inserted in the flow, a wide range of behaviors have been observed depending on the flow speed, from superfluid flow to super-sonic Mach cones, to the nucleation of topological excitations such as solitons and vortices.

I will then proceed with the presentation of more recent work on synthetical gauge fields for photons and, more generally, geometrical and topological effects in quantum fluids of light in the presence of periodic trapping potentials with different geometries.

Perspectives towards the generation of strongly correlated photon gases in the presence of strong optical nonlinearities will be finally sketched, with a special attention to quantum Hall liquids of light and the detection of their exotic quasi-particle excitations.