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Calendar of Physics Talks Vienna
| Speaker: | Samuel Kovacik (Comenius University Bratislava) |
| Abstract: | Recently, a matrix formulation of a three-dimensional quantum space was proposed. The basic idea is that (in)finite number of fuzzy spheres can be glued together in a specific way. During the seminar, we will discuss the construction of the model with some recent examples from field theory, quantum mechanics and classical physics. |
| Date: | Tue, 18.03.2025 |
| Time: | 14:00 |
| Duration: | 60 min |
| Location: | Erwin-Schroedinger-HS, Boltzmanngasse 5, 1090 Wien, 5.Stock |
| Contact: | S. Fredenhagen, M. Sperling |
| Quantum Cooling with Complex Machines |
| Speaker: | Jake Xuereb (TU Wien, Atominstitut) |
| Abstract: | When unitarily cooling a quantum system by accessing a larger quantum system (the âÂÂmachineâ or reservoir), how does the machineâÂÂs structure impact both the achievable cooling and the complexity of the required protocol? Cooling a single qubit with identical qubits is the well-known algorithmic cooling problem, with applications to quantum computing and the foundations of quantum thermodynamics. In this talk, I will discuss our work generalizing this scenario to a qubit coupled to nn qubits that can differ in energy gaps and temperatures. We provide a characterization of these more complex machines using a set of inequalities, which allow us to derive universal limits on the achievable coolingâÂÂakin to a Carnot bound. We then translate the problem into graph-theoretic terms, framing cooling unitaries as minimum-weight perfect matchings; this approach systematically identifies efficient coo |
| Date: | Wed, 19.03.2025 |
| Time: | 16:15 |
| Location: | Atomistitut, Helmut Rauch Hoersaal, Stadionallee 2, 1020 Wien |
| Contact: | Maximilian Pruefer |
| Cooperative effects due to light-induced dipole-dipole forces |
| Speaker: | Uros Delic (TU Wien, Atominstitut) |
| Abstract: | Optical forces can control and trap polarizable objects such as atoms, molecules, or dielectric nanoparticles. Applications of these "optical tweezersâ in AMO physics have enabled breakthroughs in quantum computation, simulation, and metrology with neutral atoms. When applied to two polarizable objects, optical forces induce a coupling mechanism, the so-called light-induced dipole-dipole (LIDD) interactions.
In my talk, I will show that LIDD forces are fundamentally nonreciprocal [1] and that we can engineer arbitrary two-mode operations between the mechanical states of two objects: two silica nanoparticles. I will present our latest results on how nonreciprocal interactions can be used to create and study a non-Hermitian phase transition [2]. Finally, I will discuss our plans for studying LIDD forces and cooperative effects in nonreciprocally interacting quantum systems.
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| Date: | Fri, 21.03.2025 |
| Time: | 10:00 |
| Duration: | 45 min |
| Location: | Helmut Rauch Hörsaal ATI |
| Contact: | Jörg Schmiedmayer |
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