On an irregular basis various Special Seminars take place at the MPQ. The seminars are organized by scientists of our divisions, administration or staff representatives.
The location will be announced with the event.
Precision measurements of the Rydberg spectra of H, He and H2 will be presented, which aim at determining their ionization energies and, in the case of H2, also the spin-rovibrational energy-level structure of H2+. These measurements are carried out for comparison with the results of first-principles calculations that include the treatment of finite-nuclear-size effects and relativistic and quantum-electrodynamics corrections up to high order in the fine-structure constant.
The field of quantum computation heavily relies on the belief that quantum computation violates the extended Church Turing thesis, namely, that quantum many-body systems cannot be simulated by classical ones with only polynomial overhead. Importantly, we must ask: what experimental evidence do we have for this bold assumption? A major effort towards providing such evidence had concentrated on random quantum circuit sampling (RCS) as in the famous supremacy experiment by Google from 2019. I will describe a recent work with Gao, Landau, Liu and Vazirani in which we give a polynomial time classical algorithm for simulating such RCS experiments. Our algorithm gives strong evidence that RCS cannot be the basis for near term experimental evidence for scalable exponential quantum advantage.
Mid-infrared (Mid-IR) quantum cascade lasers stand out as coherent and polarized sources, offering rapid intensity and wavelength modulation capabilities. These features enable the development of advanced sensing strategies that extend beyond traditional absorption spectroscopy, which relies on the Beer-Lambert law.