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arXiv · 2412.07381

Magnetic colloidal single particles and dumbbells on a tilted washboard moire pattern in a precessing external field

Farzaneh Farrokhzad·Nex C. X. Stuhlmüller·Piotr Kuświk·Maciej Urbaniak·Feliks Stobiecki·Sapida Akhundzada·Arno Ehresmann·Daniel de las Heras·Thomas M. Fischer
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Abstract

We measure the dynamical behavior of colloidal singlets and dumbbells on an inclined magnetic moir\'e pattern, subject to a precessing external homogeneous magnetic field. At low external field strength single colloidal particles and dumbbells move everywhere on the pattern: At stronger external field strengths colloidal singlets and dumbbells are localized in generic locations. There are however nongeneric locations of flat channels that cross the moir\'e Wigner Seitz cell. In the flat channels we find gravitational driven translational and non-translational dynamic phase behavior of the colloidal singlets and dumbbells depending on the external field strength and the precession angle of the external homogeneous magnetic field.

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Farzaneh Farrokhzad, Nex C. X. Stuhlmüller, Piotr Kuświk, Maciej Urbaniak, Feliks Stobiecki, Sapida Akhundzada, Arno Ehresmann, Daniel de las Heras, Thomas M. Fischer. 2024-12-10. Magnetic colloidal single particles and dumbbells on a tilted washboard moire pattern in a precessing external field. https://doi.org/10.1039/d4sm01183j

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