arXiv subjects

B. Wirtschafter

Publications and source records attributed to B. Wirtschafter.

4 recordsLinked to original sources

arXiv2025

An atom chip interferometer

We have realized an interferometer using a thermal cloud of magnetically trapped rubidium 87 atoms on a chip. The interferometer resembles a Ramsey interferometer with a state selective spatial splitting of the two internal states as proposed in [M. Ammar, and al., Phys. Rev. A, 91, 053623]. The splitting is effected by microwave fields from two on-chip waveguides while the atoms remain magnetically trapped. The inferred maximum separation is $1.2\pm 0.1~\mu$m. We observe interference fringes with a contrast around 8\% limited by velocity difference of the two interferometer states when we close the interferometer. We develop a model describing this contrast decay.

physics.atom-ph↗

arXiv2025

Silicon nitride based integrated photonic circuit to control a cold-atom source

We have developed a silicon nitride based photonic integrated circuit (PIC) that is responsible for the cooling, pumping and imaging of cold rubidium 87 atoms. The photonic integrated circuit consists of two chips placed next to each other and has a total area of 2x2~cm$^2$. This greatly minimizes the area needed while still having all the optical control functions to create, control and measure a magneto-optical trap (MOT). The piezo electric material Lead Zirconate Titanate (PZT) on the PIC is employed for phase shifting a Mach-Zehnder type configuration where extinction ratios up to 50 dB and switching speeds of 1 MHz are achieved. For the first time a two and three dimensional rubidium 87 MOT is realized using an active PIC. For the three-dimensional MOT, we measure $7\cdot 10^7$ atoms with a temperature of 270~$\mu$K.

physics.atom-ph↗

arXiv2025

Miniaturized optical system for a chip based cold atom inertial sensor

We miniaturized the complex optical system responsible for the cooling, pumping and imaging of an on-chip based cold atom inertial sensor. This optical bench uses bonded miniature optics and includes all the necessary optical functions. The bench has a volume of 35x25x5~cm$^3$. We developed a laser frequency lock adapted to the optical bench using saturated absorption in a rubidium cell. The entire laser source based on frequency doubling of 1.56~$\mu$m fiber lasers, including the control system and the saturated absorption module, fits in a $5U$-rack. Using the miniaturized bench, we realized two and three dimensional magneto optical traps for Rubidium 87 atoms.

physics.atom-ph↗

arXiv2025

Noise budget of a trapped on chip cold atom Rubidium 87 clock

In this paper, we present a realisation of an on chip atomic clock using a cold cloud of Rubidium 87 atoms. This clock is based on a Ramsey interferometer with a Ramsey time around 600 ms. This is realized with large lab temperature drift during the measurement (few degrees per day) and without magnetic field shielding. We review the experimental implementation of this clock and give a full study of the known noises present in this atomic clock.

physics.atom-ph↗