Controlled Manipulation of Intermediate State in a Type-I Superconductor

Abstract

The intermediate state of type-I superconductors presents a classic paradigm of modulated pattern formation, arising from the competition between short-range attractive and long-range repulsive vortex-vortex interactions. However, direct visualization and, more importantly, active control over the topology and dynamics of these flux structures have remained significant challenges, limiting our ability to manipulate them for fundamental studies and potential applications. Here, using low-temperature magnetic force microscopy, we achieve direct imaging and controllable manipulation of the flux structures in a high-purity tantalum single crystal. We systematically track the evolution of flux morphology - from tubes to stripes - during flux penetration and expulsion, revealing a pronounced topological hysteresis originating from the geometric barrier. Furthermore, we demonstrate precise local control by using the magnetic tip to drag and merge individual flux tubes and to reconfigure entire stripe domains. Under global alternating current (AC) excitation, we discover a reversible stripe-grid-stripe transition, a dynamic reorganization driven by current-induced flux penetration and pinning effects. The corresponding phase diagram shows that the threshold current decreases with magnetic field but increases with AC frequency. Our work establishes a pathway for active flux manipulation in type-I superconductors, revealing rich dynamics and paving the way for flux-based superconducting devices.

https://link.aps.org/doi/10.1103/jwy8-cqcm

References in corpus (13)

• Effective Demagnetization Factors of Diamagnetic Samples of Various Shapes
• Controlled Manipulation of Individual Vortices in a Superconductor
• Optical Manipulation of Single Flux Quanta
• The Suprafroth (Superconducting Froth)
• Equilibrium topology of the intermediate state in type-I superconductors of different shapes
• Mechanical control of individual superconducting vortices
• Topological Hysteresis in the Intermediate State of Type-I Superconductors
• Ratchet Cellular Automata
• Type-I superconductivity in ScGa3 and LuGa3 single crystals
• Impeded Growth of Magnetic Flux Bubbles in the Intermediate State Pattern of Type I Superconductors
• Current-driven transformations of the intermediate state patterns in type-I superconductors
• Nucleation and Collapse of the Superconducting Phase in Type-I Superconducting Films
• Dynamic Formation of Metastable Intermediate State Patterns in Type-I Superconductors