Atomic Interferometer with Amplitude Gratings of Light and Its Applications to Atom Based Tests of the Equivalence Principle

Abstract

We have developed a matter wave interferometer based on the diffraction of atoms from effective absorption gratings of light. In a setup with cold rubidium atoms in an atomic fountain the interferometer has been used to carry out tests of the equivalence principle on an atomic basis. The gravitational acceleration of the two isotopes 85 Rb and 87 Rb was compared, yielding a difference ∆g/g = (1.2 ± 1.7) · 10 −7 . We also perform a differential free fall measurement of atoms in two different hyperfine states, and obtained a result of ∆g/g = (0.4 ± 1.2) · 10 −7 .

Squeezed-light-enhanced atom interferometry below the standard quantum limit

“…Further increases to the sensitivity of atom interferometers would allow for some exciting science, such as improved tests of the weak equivalence principle [16][17][18], searches for quantum gravitational effects [19], and the measurement of gravitational waves [20,21]. Current state-of-the-art atom interferometers utilize uncorrelated sources, which can operate no better than the standard quantum limit (SQL)-i.e., the sensitivity scales as 1/ √ N where N is the number of detected atoms.…”

Atom interferometers and optical atomic clocks: New quantum sensors for fundamental physics experiments in space

“…In particular, atom interferometers are new tools for experimental gravitation as, for example, for precision measurement of gravity acceleration [15], gravity gradients [16], Newtonian gravitational constant G [17], gravity at micrometric distances [18,19], and for testing equivalence principle [20]. The possibility of detecting gravitational waves by atom interferometry was also discussed [21,22].…”

Recoil-Sensitive Lithium Interferometer without a Subrecoil Sample

“…They are used for inertial sensing [2,3], gravity gradiometry [4] and tests of fundamental physics [5][6][7][8][9][10][11][12][13][14][15]. Ramsey-Bordé interferometers, in particular, measure the mass m of an atom through the kinetic energy ω r = 2 k 2 /(2m) it gains after recoiling from the interaction with a photon ( is the reduced Planck constant).…”