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Table 5 Overview of the experimental capabilities of BECCAL

From: The Bose-Einstein Condensate and Cold Atom Laboratory

Atom numbers

Single 87Rb BEC

≥1 × 106

Single 41K BEC

≥1 × 105

Dual-species BEC of 87Rb and 41K (respectively)

≥1 × 105, ≥1 × 104

Trapped 85Rb atoms

≥1 × 106

Trapped 39K atoms

≥1 × 105

Trapped 40K atoms

≥1 × 104

Atom trapping and manipulation

Magnetic traps: available structures

Atom chip and four pairs of coils

Crossed optical dipole trap: wavelength, beam waist, total power

1064(10) nm, 100(20) μm, 300 mW

Optical lattice

Switchable retro-reflection of the beams of the crossed optical dipole trap

Painted potentials: barrier height, sizes of rings, total power

5 μK with contour length ≤ 100 μm and refresh rate ≥100 Hz, inner diameter 20 μm to 1500 μm and outer diameter 40 μm to 2000 μm, 50 mW optical power at 764 nm

Life times of single species clouds: non-trapped, magnetically, and optically trapped (respectively)

≥10 s, ≥3 s, ≥10 s

Feshbach-field

≥175 G with tunable modulation of up to 1 G at ≥0.1 kHz

Transport of atoms away from the chip

0.1 mm to 2 mm

Minimum expansion velocity for 87Rb, 41K, and 87Rb-41K mixtures after atomic lensing

≤100 μm s−1

Two independent radio-frequency sources

0.1 MHz to 25 MHz with Rabi frequency ≥10 kHz and ramp rates ≥100 MHz s−1

Microwave generator

6.835 GHz, 3.036 GHz, 1285 MHz, 462 MHz and 254 MHz adjustable with 30 MHz around the central frequency, Rabi frequency ≥10 kHz and ramp rates ≥100 MHz s−1

Atom interferometry, two independent axes

Primary axis

parallel to Earth’s acceleration (nadir) and parallel to the chip surface

Total free evolution time

≥2T = 2.6 s

Raman diffraction beams

splitting efficiency ≥ 90%, \(1/e^{2}\) beam diameter ≥ 6 mm, Rabi frequency 1 kHz to 50 kHz, detuning adjustable 1 GHz to 5 GHz, homogeneous magnetic field of 0.05 G to 1 G, power of 15 mW (70 mW) per frequency component in primary axis (secondary axis)

Rotation compensation

retro-reflection mirror on tip-tilt stage for rotation compensation of ISS for times ≥2T = 2.6 s (≥3 mrad)

Coupling with external sensors

rotation sensor with noise floor ≤ 50 μrad s−1/\(\sqrt{\mathrm{Hz}}\)

Secondary axis

perpendicular to the orbital plane and perpendicular to the chip surface

Two orthogonal, species selective, spatially resolved absorption detection systems

Spatial resolution

≤10 μm

Field of view

≥10 mm2

Scanning range of focal plane

≥10 mm,

Adjustable depth of field

100 μm to 2000 μm

Fluorescence detection

single axis, species selective

Miscellaneous

 

Multiple surfaces with different electrical properties on the atom chip

size ≥ 1 mm2