Speaker
Description
This work is part of the international GRASIAN collaboration (https://grasian.ue). One goal of this collaboration is to demonstrate the existence of Gravitational Quantum States (GQSs) of Hydrogen atoms, using a cryogenic Hydrogen beam and an atomic mirror and absorber setup, located at Marietta Blau Institute. GQSs settle when particles are trapped in a triangular potential well made, on the bottom side of an infinite barrier of potential, and on the upper side of gravitational potential energy. The existence of such quantum states has been experimentally demonstrated for neutrons [1] and remains to be observed for Hydrogen.
Due to Heisenberg time-energy inequality, we show that observation time in current setup is not sufficient in order to resolve higher levels of the GQSs. The current 6K source which has corresponding velocities following a Maxwell-Boltzmann distribution with a peak around 400 m/s [2,3], does not allow this resolution.
As a response, the development of a Zeeman decelerator for the Hydrogen atoms taking advantage of their paramagnetic properties, is being made by our team (LKB) in Paris, in partnership with the Laboratoire Aimé Cotton (Orsay, France), with the group of D. Comparat, R. Mathevet from the LNCMI (Laboratoire National des Champs Magnétiques Intenses, Toulouse, France), and the MBI (Vienna, Austria) with the group of E. Widmann.
This poster deals with the physical principle behind the Zeeman decelerator [4,5], as well as the experimental development and numerical work that have been done in this direction.
[1] V. Nesvizhevsky et al., Quantum states of neutrons in the Earth’s gravitational field, Nature 415, 297 (2002)
[2] C. Killian et al., GRASIAN: towards the first demonstration of gravitational quantum states of atoms with a cryogenic hydrogen beam, The European Physical Journal D volume 77, Article number: 50 (2023)
[3] C. Killian et al., GRASIAN: Shaping and characterization of the cold hydrogen and deuterium beams for the forthcoming first demonstration of gravitational quantum states of atoms (2024)
[4] P. Jansen, F. Merkt, Manipulating beams of paramagnetic atoms and molecules using inhomogeneous magnetic fields, Elsevier (2020)
[5] T. Cremers, N. Janssen, E. Sweers, S. Y.T. van de Meeraker, Design and construction of a multistage Zeeman decelerator for crossed molecular beams scattering experiments, Rev. Sci. Instrum. 90 (2019)