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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