Gravitation-induced quantum interference for neutrons
Classically, the neutron will just fall as a mass in a gravitational field like any other particle. This has been experimentally detected in 1965 by Dabbs and repeated with increased accuracy by Koester and Schiedmayer. The results are a correspondence up to the measurement accuracy of 0.02 %. In the wave picture, one can split the wave function into wave packets and let them travel through different potentials (heights) through this gravitational field. Already in 1975 Colella, Overhauser and Werner showed, using a perfect crystal interferometer for neutrons, that a quantum mechanical phase of the neutron is induced by the average height difference of these wave functions (COW experiments). The quantum gravitational effect was also measured on OffSpec, proving that these measurements can be done at OffSpec with a precision of 0.1% accuracy. We propose to investigate the spin gravity coupling and find an estimate of the coupling constant, k. Another possible outcome could be an upper limit of k in case of neutrons.