Abstract

In our group we have developed an interferometry based technique which is capable of controlling and measuring the rotational projection quantum state of ground state hydrogen molecules, before and after they collide with a surface [1-3]. The technique is based on ultra-low-energy (pico eV) manipulations using a series of inhomogeneous and homogeneous magnetic fields. The complexity of the interference patterns we can measure allows us to quantitatively measure changes of the complex amplitudes of the rotational wave function, which in turn are extremely sensitive to the interaction potential the molecule experienced during the scattering event. During the seminar I will explain the technique and show examples for the type of information that can be obtained from rotationally elastic and rotationally inelastic scattering experiments. I will show how our results compare with state-of-the-art DFT based calculations and briefly present a new direction we are examining, which is the possibility of extracting empirically based 6d potential energy surfaces directly from measurements.

[1] Nat. Comms.8, 15357 (2017) [2] Nat. Comms.11, 3110 (2020) [3] Nat. Comms.13, 2287 (2022)