Download New atom interferometry techniques for tests of fundamental

PhD application
New atom interferometry techniques for tests of fundamental physics
Laboratory: SYRTE, UMR 8630 - Observatoire de Paris, 77 avenue Denfert Rochereau, 75014 Paris
Supervisor/contact: Remi GEIGER, [email protected] ; +33(0)1.40.51.22.08
Website: https://syrte.obspm.fr/spip/science/iaci/
Abstract: Atom interferometers offer interesting applications in geophysics, inertial sensing, metrology and
tests of fundamental physics. Addressing these applications requires to push further the performances of cold
atom inertial sensors, in particular for applications in fundamental physics (detection of gravitational waves
or tests of the Einstein Equivalence Principle) or in geoscience (non-invasive observations of underground
mass transfers). This PhD thesis project aims at significantly pushing the sensitivity of cold atom inertial sensors
by studying new atom interferometry (AI) techniques and their implementation for precision tests of
fundamental physics. Besides the impact on future large scale gravitation observatories using cold atoms,
major breakthroughs are expected in metrology, geophysics and inertial navigation.
The PhD work will be mainly of experimental nature and carried out on the high sensitivity cold atom
gyroscope-accelerometer experiment based at the SYRTE laboratory in Paris, France. This experiment is the
state of the art in terms of rotation sensitivity for cold atom inertial sensors. The experiment relies on atom
interferometry using coherent superpositions of quantum states of Cesium atoms manipulated by lasers. The
superpositions are obtained by two (or more) photon transitions which transfer momentum to the atom and
play the role of beam splitters and mirrors for the matter wave.
You will first participate to improving the sensitivity of the gyroscope by studying the implementation of multiphoton transitions in order to achieve large momentum transfer (LMT) beam splitters. To this end, you will
study the effect of an optical cavity to enhance the laser light power seen by the atoms and thus reach high
efficiency LMT pulses. You will use your skills in optics, atomic and quantum physics and instrumentation.
More generally, you will work on the development of a two-axis gyroscope to reach a long term stability of
10−12 rad/s, which represents an improvement of 3 orders of magnitude compared to the state of the art.
Such a stability level will allow to study geophysical effects affecting the Earth rotation, and will open the
possibility to perform fundamental tests of physics. You will in particular work on a test of Lorentz invariance
(a fundamental symmetry of the standard model and of general relativity) by atom interferometry with the
gyroscope-accelerometer experiment, in collaboration with the theory team at SYRTE.
Key words: atom interferometry, inertial sensor, cold atoms, test of fundamental physics.