Seminars

In this talk I shall illustrate how ultracold quantum systems of atoms and ions can be used for quantum simulation and information processing as well as for investigating many-body quantum physics. I shall thus present a few theoretical examples on how to control an atomic bosonic Josephson junction with a single trapped ion, the formation of molecular ions, and how to engineer long-ranged atom-ion interactions with laser fields and Rydberg excitations. [more]

In this talk I will speak about our source of light-matter quantum states based on laser-cooled atoms. In particular, I will explain the capabilities developed in order to transfer photonic qubits from this system to another matter platform that consists on a crystal doped with rare-earth ions. Photonic qubits generated by the atomic cloud were frequency converted and temporally shaped in order to have an optimum interaction with the ions in the crystal. These capabilities enabled to perform quantum state transfer between these two very different matter systems: the laser-cooled gas and the crystal. [more]

I will introduce a specific method how to generalize cMERA in presence of interactions. The method is based on Hamiltonian renormalization of spatial degrees of freedom. Using this method I will work out a circuit starting from an appropriate IR state and ending up with the vacuum state of phi^4 theory. [more]

Firstly, I will deal with a new way of accelerating charged particles based on femtosecond laser pulses and nanophotonic structures. The concept is exactly the same as in classical RF and microwave accelerators, only with roughly five orders of magnitude faster oscillating driving fields and structures that are smaller by the same factor. With the help of such small lithographically produced dielectric structures we have demonstrated not only efficient acceleration of electrons, but also deflection and focusing. Currently, we are building a prototype "accelerator on a chip". The current status will be reported. [more]

The arrival time statistics of spin-1/2 particles governed by Pauli's equation, and defined by their Bohmian trajectories, show unexpected and very well articulated features. Comparison with other proposed statistics of arrival times that arise from either the usual (convective) quantum flux or from semiclassical considerations suggests testing the notable deviations in an arrival time experiment, thereby probing the predictive power of Bohmian trajectories. The suggested experiment, including the preparation of the wave functions, could be done with present-day experimental technology. [more]