A chip-based superconducting magnetic trap for levitating superconducting microparticles

TL;DR

This paper demonstrates a chip-based superconducting magnetic trap capable of levitating superconducting microparticles ranging from 0.5 to 200 micrometers in diameter, using a novel silicon chip design with niobium coils at cryogenic temperatures.

Contribution

It introduces a new superconducting chip-based magnetic trap design for levitating microparticles, enabling quantum experiments with larger particles in a compact setup.

Findings

Successful trapping of 50 μm diameter SnPb microparticles at 4 K and 40 mK.

Fabrication of a dual-chip superconducting coil system generating a quadrupole magnetic field.

Demonstration of stable levitation of superconducting microparticles in a chip-based device.

Abstract

Magnetically-levitated superconducting microparticles have been recently proposed as a promising platform for performing quantum experiments with particles in the picogram regime. Here, we demonstrate the superconducting technology to achieve chip-based magnetic levitation of superconducting microparticles. We simulate and fabricate a chip-based magnetic trap capable of levitating superconducting particles with diameters from 0.5$\,\mu$m to 200$\,\mu$m. The trap consists of two stacked silicon chips, each patterned with a planar multi-winding superconducting coil made of niobium. The two coils generate a magnetic field resembling a quadrupole near the trap center, in which we demonstrate trapping of a spherical 50\,$\mu$m diameter SnPb microparticle at temperatures of 4\,K and 40\,mK.