arXiv subjects

P. -P. Crépin

Publications and source records attributed to P. -P. Crépin.

3 recordsLinked to original sources

arXiv2019

Quantum interference test of the equivalence principle on antihydrogen

We propose to use quantum interferences to improve the accuracy of the measurement of the free fall acceleration g of antihydrogen in the GBAR experiment. This method uses most antiatoms prepared in the experiment and it is simple in its principle as interferences between gravitational quantum states are readout without transitions between them. We use a maximum likelihood method for estimating the value of g and assess the accuracy of this estimation by a Monte-Carlo simulation. We find that the accuracy is improved by approximately three orders of magnitude with respect to the classical timing technique planned for the current design of the experiment.

quant-ph↗

arXiv2017

Quantum reflection of antihydrogen from a liquid helium film

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 anni- hilation for as long as 1.3s on a bulk of liquid 4He, and 1.7s for liquid 3He. 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.

physics.atom-ph↗

arXiv2017

Casimir-Polder shifts on quantum levitation states

An ultracold atom above a horizontal mirror experiences quantum reflection from the attractive Casimir-Polder interaction, which holds it against gravity and leads to quantum levitation states. We analyze this system by using a Liouville transformation of the Schrödinger equation and a Langer coordinate adapted to problems with a classical turning point. Reflection on the Casimir-Polder attractive well is replaced by reflection on a repulsive wall and the problem is then viewed as an ultracold atom trapped inside a cavity with gravity and Casimir-Polder potentials acting respectively as top and bottom mirrors. We calculate numerically Casimir-Polder shifts of the energies of the cavity resonances and propose a new approximate treatment which is precise enough to discuss spectroscopy experiments aiming at tests of the weak equivalence principle on antihydrogen. We also discuss the lifetimes by calculating complex energies associated with cavity resonances.

quant-ph↗