Source: National Natural Science Foundation of China

Grant No:91736311

Project:High-precision Test of Weak Equivalence Principle with Atom Interferometry

Chief Specialist: Prof.Jin Wang

Abstract:

    In recent years, the precision of the weak equivalence principle test based on atom interferometry is 3-4 orders of magnitude higher than that of the neutron-based test. Among them, the precision of Rb-85 and Rb-87 dual atom interferometer based weak equivalence principle test achieves 10^[-8] level, and the test precision with different spin-orientated Rb-87 (mF=±1) atoms achieves 10^[-7] level, both works were finished by members of this project team, and they are at leading level in the world. How to further improve the precision of micro-particle based weak equivalent test, is an important problem in atom interferometer based precision measurement physics. The weak equivalence principle tests using different type atom interferometers need to solve a common problem, which is the preparation of ultra-cold atomic source. Fortunately, our recent work on preparation of Twin-Fock Bose-Einstein condensate provides a new technical approach for the preparation of ultra-cold mixed Rb atom gases. This project will integrate the research advantages of Rb-85 and Rb-87 dual atom interferometer, different spin-oriented Rb-87 (mF=±1) atom interferometer, and preparation of ultra-cold mixed Rb atom gases, and to carry out a more accurate weak equivalence principle test using cold atom interferometers, so that to make the micro-particle based WEP test in China keeping the leading level around the world.