Key experiments in quantum science and technology with photons, ions and atoms (MVSem)

Sommersemester 2025
Dozent: Schmitt J, Sturm S
15 Teilnehmer/innen

Modern experiments have realised an extraordinary degree of control of isolated quantum systems. With a variety of experimental platforms, including photons, ions and neutral atoms it becomes possible to address the fundamental laws that govern quantum mechanics. A large toolbox has emerged that allows tackling different topics from high precision test of fundamental theories using single particles to quantum sensing and quantum simulation on few and many-body systems, up to the synthesisation of states of matter with a topologically nontrivial character. 

In this seminar we will discuss key experiments in this field. Each student will give a 30min presentation on one of the topics offered. The preparation of this presentation will include 2-3 meetings with the respective tutor to discuss the physics as well as the structure of the talk. Special emphasis should be devoted to the clarity of the experimental claims and techniques. After the presentation, a one-page summary should be provided. Further, it is expected that the students attend all presentations and participate with active feedback and questions. 

The seminar takes place on Fridays from 11:15 to 13:00. In the first seminar date (25/04/2024), we will give an introduction and each student will choose a topic. The topics will be announced after when the seminar is open for registration.

Info

  • Room: KIP, INF 227, 03.404 (3rd floor)

  • Seminar times: 11:15-13:00 o'clock, on the given dates on Fridays.

Topics

Below is a list of available topics for presentations in this seminar, each containing a description with central aspects to be covered. The relevant literature will be provided by the lecturers.
  • Fr   16.5.2025 11:15   Laser Cooling and Trapping (*)
    Pylyp Filippov
    Introduce the basis for ultracold neutral experiments. Discuss the basics of atom-field interactions, and the concepts of Zeeman slowing, optical molasses, and magneto-optical trapping, cooling limits (Doppler and sub-Doppler).
  • Fr   23.5.2025 11:15   Bell Test Measurements (*)
    Gabriele Guarino
    Discuss the basics for quantum information. Introduce some of the concepts of quantum mechanics, e.g. measurement postulate, Heisenberg uncertainty principle, angular momentum, entanglement. Discuss the EPR paradox, the hidden variable theory, Bell inequality, and its experimental tests.
  • Fr   23.5.2025 12:15   Quantum Teleportation and Quantum Key Distribution
    Florian Kaiser
    Discuss the use of Bell-test-type experiments for quantum information transfer, quantum communication protocols and their intrinsic advantages (no-cloning theorem), classical and quantum communication channels, and examples of realizations.
  • Fr   30.5.2025 11:15   Precision mass determinations and test of matter/antimatter symmetry in ion traps
    Mira Eowyn Newe
    Introduce the concept of Penning trap, cooling and detection methods of ions, and applications for fundamental physics: weighing atomic excitations, testing E=mc^2.
  • Fr   30.5.2025 12:15   g-2: the electron magnetic moment 
    Srijana Rao
    Introduce the g-factor and Feynman diagrams. Discuss continuous Stern Gerlach effect, spin anomaly, muon vs electron, cavity interactions and shifts, quantum cyclotron and Landau levels, fine-structure constant, physics beyond the standard model. 
  • Fr   6.6.2025 11:15   Bose-Einstein condensation of neutral atoms (*)
    Cedric Vincent Becker
    Discuss experiments achieving BEC in dilute atomic gases. Introduce concept of magnetic and optical trapping of neutral atoms, evaporative cooling, absorption imaging, Bose-Einstein distribution, BEC phase transition, spontaneous symmetry breaking, phase coherence, and superfluidity. 
  • Fr   6.6.2025 12:15   Superfluidity in lower dimensions
    Robert Schneiker
    Discuss the realization of atomic quantum gases in low-dimensional optical traps, suppression of long-range order, Mermin-Wagner theorem, topological BKT superfluidity in 2D, elementary excitations as vortices and phonons, along with a discussion of the key experiments.
  • Fr   13.6.2025 11:15   Cavity Quantum Electrodynamics Experiments (*)
    Moritz Linnebacher
    Introduce the description of light in high finesse cavity, modification of the modes, and the light-matter-interaction. Discuss Jaynes-Cummings Hamiltonian, modified spontaneous emission, strong and weak coupling regimes, quantum Rabi oscillations, and the non destructive measurement of of photon states, as the key experiment.
  • Fr   13.6.2025 12:15   Interacting photons: Photon Blockade
    Leonie Marzel
    Discuss one of the illustrative examples of cavity QED experiments: the photon blockade. Introduce light matter interaction of a single atom in an optical cavity, photon antibunching, and discuss the nonlinear effect introduced by the atom, leading to photon interactions. 
  • Fr   27.6.2025 11:15   Room-temperature Bose–Einstein condensation of photons
    Luca Yannik Geißler
    Discuss the basics for trapping photons in optical microcavities, with modified mode structure, two-dimensional dispersion and photon thermalization with molecules. Discuss the concept of Bose-Einstein condensation of photons at room temperature in harmonic and box potentials, and grand canonical particle number fluctuations. 
  • Fr   27.6.2025 12:15   Photonic Quantum Computing
    Michel Thiery
    Discuss the basics of gate-based quantum computing and the concept of universal gates. Discuss historical (e.g. first implementation of a cNOT gate) and modern implementation with photons. Discuss challenges, e.g. quantum error corrections, single qubit operations with linear elements, KLM scheme, integration, and boson sampling. 
  • Fr   4.7.2025 11:15   Quantum Computing with linear ion chains
    Nick Peter Zobel
    Rediscuss same concepts as for photonic quantum computing (gates) but implementation with ions. Cirac-Zoller scheme, linear ion crystals, experimental achievements and challenges.
  • Fr   4.7.2025 12:15   Quantum simulation with ions in Penning traps
    Julius Römer
    Discuss 2D Coulomb crystals of ions, rotation locking, electromagnetically-induced-transparency cooling, optical detection of ions, quantum simulation of Ising models.
  • Fr   11.7.2025 11:15   Atoms in optical tweezer arrays
    Jiayi Liu
    Discuss the trapping of individual atoms in a optical dipole microtrap, known as an optical tweezer, their loading and cooling schemes and schemes to control their arrangement in 1D, 2D and 3D.
  • Fr   11.7.2025 12:15   Quantum Simulation with Rydberg-atom arrays
    Juan Carlos Provencio Lameiras
    Discuss the generation of interactions between Rydberg atoms in arrays of optical tweezers, and the experimental achievements on simulation of quantum spin models (Ising, XY, ...) and topological models (SSH), as well as their prospects for computation.
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Key experiments in quantum science and technology with photons, ions and atoms (MVSem)
Sommersemester 2025
Schmitt J, Sturm S
15 Teilnehmer/innen
Termine