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Maarten T. M. Christenhusz

Publications and source records attributed to Maarten T. M. Christenhusz.

2 recordsLinked to original sources

A high-speed, large-aperture 3D printed laser shutter for cold atom experiments

Cold atom experiments require optical shutters with rapid and repeatable actuation. Existing solutions often involve high cost, limited aperture diameter and slow transitioning. We present a 3D-printable shutter design featuring a large aperture of 4.5 mm diameter, low-cost assembly, and robust performance. The device achieves switching times of $399\pm8~μ$s with delays of $2.7\pm0.2$ ms for a fully illuminated aperture, with four different shutters demonstrating repeatable performance. We measure the shutter speed to be $7.0\pm0.1$ m/s. This approach offers an accessible, scalable solution for cold atom and other optical experiments requiring multiple shutters with precise light control and avoids the need to resize or precision-align a beam through an aperture.

cond-mat.quant-gas↗

Emergent Universal Drag Law in a Model of Superflow

Despite the fundamentally different dissipation mechanisms, many laws and phenomena of classical turbulence equivalently manifest in quantum turbulence. The Reynolds law of dynamical similarity states that two objects of same geometry across different length scales are hydrodynamically equivalent under the same Reynolds number, leading to a universal drag coefficient law. In this work we confirm the existence of a universal drag law in a superfluid wake, facilitated by the nucleation of quantized vortices. We numerically study superfluid flow across a range of Reynolds numbers for the paradigmatic classical hard-wall and the Gaussian obstacle, popular in experimental quantum hydrodynamics. In addition, we provide a feasible method for measuring superfluid drag forces in an experimental environment using control volumes.

cond-mat.quant-gas↗