Spherical agglomeration of superconducting and normal microparticles with and without applied electric field

TL;DR

This paper investigates the formation of spherical agglomerates of microparticles, including superconducting and normal materials, revealing that such structures form independently of electric fields and superconductivity, challenging previous assumptions.

Contribution

It demonstrates that spherical agglomeration occurs without electric fields and above superconducting transition temperatures, expanding understanding of particle assembly phenomena.

Findings

Ball formation occurs without electric fields.

Agglomeration happens at temperatures above T_c.

Non-superconducting materials also form spherical clusters.

Abstract

It was reported by R. Tao and coworkers that in the presence of a strong electric field superconducting microparticles assemble into balls of macroscopic dimensions. Such a finding has potentially important implications for the understanding of the fundamental physics of superconductors. However, we report here the results of experimental studies showing that (i) ball formation also occurs in the absence of an applied electric field, (ii) the phenomenon also occurs at temperatures above the superconducting transition temperature, and (iii) it can also occur for non-superconducting materials. Possible origins of the phenomenon are discussed.