Advances in precision contrast interferometry with Yb Bose-Einstein condensates

Abstract

Using a three-path contrast interferometer (CI) geometry and laser-pulse diffraction gratings, we create the first matter-wave interferometer with ytterbium (Yb) atoms. We present advances in contrast interferometry relevant to high-precision measurements. By comparing to a traditional atom interferometer, we demonstrate the immunity of the CI to vibrations for long interaction times (> 20 ms). We characterize and demonstrate control over the two largest systematic effects for a high-precision measurement of the fine structure constant via photon recoil with our interferometer: diffraction phases and atomic interactions. Diffraction phases are an important systematic for most interferometers using large-momentum transfer beam splitters; atomic interactions are a key concern for any BEC interferometer. Finally, we consider the prospects for a future sub-part per billion photon recoil measurement using a Yb CI.

High-Resolution Atom Interferometers with Suppressed Diffraction Phases

“…Using multiphoton Bragg diffraction [4,5] and simultaneous operation of conjugate interferometers [6], the phase difference has been increased to Φ = 16n 2 ω r T (where the factor of 16 arises from taking the phase difference of the two interferometers), and Earth's gravity and vibrations have been canceled. Unfortunately, however, Bragg diffraction causes a diffraction phase [2,[7][8][9], which has been the largest systematic effect in high-sensitivity atom interferometers using this technique [2]. Here, we study the diffraction phase in detail and show that it can be suppressed and even nulled by introducing Bloch oscillations as shown in Fig.…”

Controlling the multiport nature of Bragg diffraction in atom interferometry

“…The sensitivity of the apparatus was improved by the addition of AC Stark shift compensation, which permits direct experimental study of sub-part-per-billion (ppb) systematics. This upgrade allows for a 310 k momentum transfer, giving an unprecedented 6.6 Mrad measured in a Ramsey-Bordé interferometer.Atom interferometers have been used for tests of fundamental physics such as the isotropy of gravity [1], the equivalence principle [2-5], the search for dark-sector particles [6,7], and measurements of the fine structure constant α [8,9], which characterizes the strength of the electromagnetic interaction. This constant can be obtained from the electron's gyromagnetic anomaly g e − 2.…”

Bragg gravity-gradiometer using the1S0–3P1intercombination transition of88Sr

“…The interest in alkaline-earth-metal (-like) atoms for precision interferometry has grown rapidly during the last decade because of their unique characteristics [7,14,15,[17][18][19][20][21]. For instance, their 1 S 0 ground state has zero angular momentum and, in particular, bosonic atoms such as the 88 Sr isotope do not even have a nuclear spin, so their ground state has zero magnetic moment at first order.…”