Simultaneous differential measurement of a magnetic-field gradient by atom interferometry using double fountains

Abstract

Precisely measuring the magnetic-field gradient within a vacuum chamber is important for many precision experiments and can be realized by atom interferometry using magnetically sensitive sublevels at different times to make a differential measurement, which had been demonstrated in our previous work. In this paper, we demonstrate a differential method to measure the magnetic-field gradient by means of two simultaneously operated atom interferometers using double atomic fountains. By virtue of this simultaneous differential measurement to reject common-mode noise, the resolution can be improved by one order of magnitude for about a 1000-s integration time.

Towards a juggling 87Rb atomic dual fountain

“…2 Applications of AIs stretch from high-precision apparatus, such as gyroscopes, 3 gravimeters, 4-6 gravity gradiometers [7][8][9] and magnetic gradiometers, 10 to the measurement of physical constants, such as fine structure constant, 11 gravitational constant, 12 quadratic Zeeman coefficient, 13 etc.…”

Raman pulse duration effect in high-precision atom interferometry gravimeters

“…(9). The action of the Raman pulse can be described generally by U laser θ; ϕ cos θ 2 −i sin θ 2 e iϕ −i sin θ 2 e −iϕ cos θ 2 :…”

“…Atom interferometry with high sensitivity plays an important role in many precision measurements [1][2][3][4][5][6][7][8][9][10]. Gravimeters based on atom interferometry have shown impressive results with high sensitivity (∼10 −8 g Hz −1∕2 ) [11][12][13][14][15][16].…”

Performance of a cold-atom gravimeter with an active vibration isolator

“…The atomic cloud is then launched along the vertical direction to a height of 0.78 m by setting the frequency difference between up-and down-shooting trapping beams, and atoms are further cooled down to a temperature of 7 μK in a moving molasses stage. The interferometry region is surrounded by a multilayer μ-metal shield to reduce the impact of external magnetic field inhomogeneity, and the magnetic field inside the vacuum chamber was measured by the atom interferometry method [37,38]. The Raman beams are realized with an optical phase-locked loop method, which is also described in detail in Ref.…”