The lecturers of the Department of Physics at Paderborn University invite all interested parties to the physics colloquium of the summer semester 2023. The colloquium will take place on Thursdays at 4.15 pm in lecture hall A1. On Thursday, 13 April, Prof. Dr. Walter Pfeiffer from Bielefeld University will talk about "Ultrafast Nanoscale Quantum Optics". The language of the event is English.
Ultrafast Nanoscale Quantum Optics
Quantum systems exhibit more degrees of freedom than classical systems because any superposition of the eigenstates is a valid physical state. For example, non-classical states of electromagnetic fields make it possible to overcome the classical shot-noise limit in phase sensing interferometers. For transverse optical fields such quantum states of light are well understood and, for example, can propagate over huge distances. In contrast the situation is much more complicated for optical near fields, i.e., longitudinal modes of the electromagnetic fields that are confined on nanoscale dimensions.
Because of the presence of matter excitation these excitations are extremely short lived and direct local probing of quantum states has up to now been impossible. After a general introduction to the field of nanoscale quantum optics this colloquium will focus on the first direct identification of a plasmon polariton quantum wave packet based on two-dimensional photoelectron spectroscopy. This recent experiment opens both pathways for generating and probing of non-classical plasmon polaritons which might enable new functionalities in nanophotonics.
