The dynamics of a quantum wave packet of a neutron bouncing under the influence of gravity - Newton's law and the question of extra dimensions of space-time
Final Report Abstract
The qBounce experiment tests Newton’s gravity law at short distances with a quantum interference technique. Our solution is to use the interaction of a macroscopic system, here a mirror for neutron reflection, with a purely quantum mechanical system, i.e. the excitation of bound quantum states of a neutron in the gravity potential of the Earth. In this project, we studied the dynamics of a quantum wave packet of a neutron bouncing under the influence of gravity. The neutron was prepared in the ground state and then falling down a step of several micrometers. The Schrödinger wave function shows the expected aspects of quantum interference, as it evolves with time. It was opening the way to a new technique for gravity experiments, which can also be used for a test of the Standard Model of Particles and Fields. The demonstration of a coherent superposition of quantum eigenstates in the gravity potential lead to a verification of a new resonance spectroscopy technique, which does not rely on electromagnetic fields or a coupling to electromagnetic potentials. Instead, a vibrating mirror is used to couple different quantum states in the gravity potential of the earth. The new spectrometer has been used as a new search strategy for dark matter or dark energy particles.
Publications
- Q-BOUNCE-Experiments with quantum bouncing ultracold neutrons, Nucl. Instrum. Meth.A 611 318 (2009)
Tobias Jenke, David Stadler, Hartmut Abele, Peter Geltenbort
- QuBounce: the dynamics of ultra-cold neutrons falling in the gravity potential of the Earth, Nuclear Physics A827, 593c (2009)
H. Abele et al.
- Ramsey’s method of separated oscillating fields and its application to gravitationally induced, Phys. Rev. D 81, 065019 (2010)
H. Abele, T. Jenke, H. Leeb, and J. Schmiedmayer
- Probing the neutron's electric neutrality with Ramsey spectroscopy of gravitational quantum states of ultracold neutrons, Physical Review D 84 036004 (2011)
K. Durstberger-Rennhofer, T. Jenke, H. Abele
- Realization of a gravity resonance spectroscopy method, Nature Physics 7 468 (2011)
T. Jenke, P. Geltenbort, H. Lemmel, Hartmut Abele
(See online at https://doi.org/10.1038/nphys1970) - Gravitation and quantum interference experiments with neutrons, New Journal of Physics 14, 055010 (2012)
H. Abele, H. Leeb
