Correlations and Disorder in Arrays of Magnetically Coupled Superconducting Rings

Dragomir Davidović; Suman Kumar; Daniel H. Reich; Jeffrey Siegel; S. B. Field; R. C. Tiberio; R. Hey; K. Ploog

doi:10.1103/PhysRevLett.76.815

Correlations and Disorder in Arrays of Magnetically Coupled Superconducting Rings

Dragomir Davidović, Suman Kumar, Daniel H. Reich, Jeffrey Siegel, S. B. Field, R. C. Tiberio, R. Hey, and K. Ploog

Phys. Rev. Lett. 76, 815 – Published 29 January 1996

Abstract

We have used ultrasensitive susceptibility techniques and scanning Hall probe microscopy to study arrays of electrically isolated micron-sized superconducting rings. The magnetic moments produced by the supercurrents in these rings are analogous to Ising spins, and neighboring rings interact antiferromagnetically via their dipolar magnetic fields. We find that there are significant antiferromagnetic correlations between rings, and effects due to geometrical frustration can be observed. Quenched disorder also plays a significant role, suppressing the development of true long-range order.

Received 17 August 1995

DOI:https://doi.org/10.1103/PhysRevLett.76.815

Authors & Affiliations

Dragomir Davidović¹, Suman Kumar¹, Daniel H. Reich¹, Jeffrey Siegel², S. B. Field², R. C. Tiberio³, R. Hey⁴, and K. Ploog⁴

¹Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218
²Department of Physics, University of Michigan, Ann Arbor, Michigan 48109
³Cornell Nanofabrication Facility, Cornell University, Ithaca, New York 14853
⁴Paul-Drude-Institut für Festkörperelektronik, D-10117 Berlin, Germany