Master – Thesis

Design and construction of a spin-flip Zeeman slower for cooling lithium-6

  • Task: Simulate, plan and build a spin-flip Zeeman slower to cool down a hot beam of atomic lithium-6. Before we can capture atoms in a magneto-optical trap they must be slowed down and cooled. A spin-flip Zeeman slower slower can efficiently slow down atoms from several hundreds m/s to almost 0. An optimal field configuration for lithium-6 has to be found, the magnets and their respective cooling system have to be built and subsequently the cooled atom beam has to be analyzed.
  • Field of study: lasers, optics, electronics, magnets
  • Contact: Marcel Willig (marcel.willig[a]


Implementation of a digital servo for feedback control of our laser systems

  • Task: Frequency stabilization of external cavity diode lasers is very important in atomic physics, where laser line-widths of less than a MHz are required. The goal of this project is to set up and implement a FPGA based digital lock-box in our current control system.
  • Fields of study: diode lasers, precision spectroscopy, PID-controllers, electronics, coding (C++)
  • Contact: Marcel Willig (mwillig[a]


(High-field) absorption imaging of ultra-cold lithium atoms

  • Task: Determination of the ion number, size and ion number density of ultra-cold atoms are nowadays a versatile tool to determine the properties of ultra-cold atoms confined in a magneto-optical trap. The standard technique relies on the imaging of the atoms by absorption spectroscopy and imaging the shadow of an atom cloud on a CCD-camera.
    We are looking for a highly motivated student to set up this method in our apparatus.
  • Fields of study: diode lasers, coding (MATLAB, Python or C++), optics, image and data analysis
  • Contact: Marcel Willig (mwillig[a]


Design and analysis of a magnetic trap for lithium

  • Task: To cool hydrogen in a cold lithium atomic cloud, a high-density trap for lihtum with a large trap volume is required. Therefore, a magnetic trap must first be designed, simulated and then tested using a cold lithium beam and laser spectroscopy.
  • Fields of study: magnetic fields, simulation, cold atomic beams, laser spectroscopy
  • Contact: Gregor Schwendler (grschwen[a]


Design and simulation of a magnetic trap for atomic hydrogen

  • Task: The low-field seeker ground-state hydrogen atoms can be trapped in a magnetic minimum. The goal of this work is to design and simulate a (permanent) magnet configuration to trap the low-velocity fraction of a cryogenic atomic hydrogen source beam prepared by a curved magnetic quadrupole guide. For trap loading, a magneto-optical trap with a cold cloud of lithium atoms acting as a buffer-gas has to be integrated in the system.
  • Field of study: magnetic fields, interactions of atoms with magnetic fields, coding (Python etc.)
  • Contact: Merten Heppener (meheppen[a]


Laser-induced ionization of atomic hydrogen

  • Task: A high quantum efficiency for detection of atomic hydrogen can be achieved by a two-step three-photon ionization at 243 nm (two-photon transition 1S-2S and subsequent photo-ionization). Goal of this project is to set up a laser system for generation of 243 nm pulses and use it to demonstrate the detection of hydrogen atoms via ionization in our apparatus.
  • Field of study: laser technology, detector physics
  • Contact: Hendrik Schürg (h.schuerg[a]


If you have an own idea for a project in mind that you would like to do in our group, please feel free to contact us!