In the atomic-, molecular and laser physics group at VU University, Amsterdam, we have two openings for PhD research (4 years), which we would like to fill a.s.a.p. We are looking for highly motivated students with an interest in experimental atomic and laser physics. An MSc degree in Physics, Applied Physics or another relevant field is a prerequisite.
Position 1: Ground state He and He+
This project aims to test quantum electrodynamics (QED) theory in the one- and two-electron atoms He+ and He. The He+ ion, in an ion trap, and the He atom, in a collimated atomic beam, will be excited from the ground state by an extreme UV frequency comb based on a femtosecond frequency comb in the infrared which is upconverted to the XUV by high-harmonic generation.
Position 2: Metastable He
This project aims to test QED theory and to measure the fine structure constant a in 3He and 4He, cooled and confined in an optical trap at a temperature of 1 microK. The atoms are in the long-lived metastable triplet state, allowing laser cooling and trapping towards Bose Einstein Condensation (4He) or Fermi degeneracy (3He). Excitation in this case is performed with a continuous wave laser.
Both projects rely on ultrastable lasers to excite atomic transitions and frequency metrology using a femtosecond frequency comb laser, locked to a GPS-controlled Rb clock. Both PhD students will work to build a frequency stabilised laser at the Hz-level