Quantum reflection of antihydrogen from a liquid helium film

P.P. Crépin (1) , E.A. Kupriyanova , R. Guérout (1) , A. Lambrecht (1) , V.V. Nesvizhevsky (2) , S. Reynaud (1) , S. Vasiliev , A.Yu. Voronin

1 LKB [Collège de France] - Laboratoire Kastler Brossel
2 ILL - Institut Laue-Langevin

We study the quantum reflection of ultracold antihydrogen atoms bouncing on the surface of a liquid helium film. The Casimir-Polder potential and quantum reflection are calculated for different thicknesses of the film supported by different substrates. Antihydrogen can be protected from annihilation for as long as 1.3 s on a bulk of liquid (4)He, and 1.7 s for liquid (3)He. These large lifetimes open interesting perspectives for spectroscopic measurements of the free fall acceleration of antihydrogen. Variation of the scattering length with the thickness of a film of helium shows interferences which we interpret through a Liouville transformation of the quantum reflection problem.

Domaines: Physique Générale [physics.gen-ph]

P.P. Crépin, E.A. Kupriyanova, R. Guérout, A. Lambrecht, V.V. Nesvizhevsky, et al.. Quantum reflection of antihydrogen from a liquid helium film. EPL - Europhysics Letters, 2017, 119 (3), pp.33001. ⟨10.1209/0295-5075/119/33001⟩. ⟨hal-01645880⟩