Imaging phase slip dynamics in micron-size superconducting rings

Abstract

We present a scanning probe technique for measuring the dynamics of individual fluxoid transitions in multiply connected superconducting structures. In these measurements, a small magnetic particle attached to the tip of a silicon cantilever is scanned over a micron-size superconducting ring fabricated from a thin aluminum film. We find that near the superconducting transition temperature of the aluminum, the dissipation and frequency of the cantilever changes significantly at particular locations where the tip-induced magnetic flux penetrating the ring causes the two lowest-energy fluxoid states to become nearly degenerate. In this regime, we show that changes in the cantilever frequency and dissipation are well-described by a stochastic resonance (SR) process, wherein small oscillations of the cantilever in the presence of thermally activated phase slips (TAPS) in the ring give rise to a dynamical force that modifies the mechanical properties of the cantilever. Using the SR model, we calculate the average fluctuation rate of the TAPS as a function of temperature over a 32-dB range in frequency, and we compare it to the Langer-Ambegaokar-McCumber-Halperin theory for TAPS in one-dimensional superconducting structures.

arXiv comment15 pages, 12 figures, version published in PRB

References in corpus (16)

• Observation of half-height magnetization steps in Sr2RuO4
• Magnetic response of mesoscopic superconducting rings with two order parameters
• Fluctuation Superconductivity in Mesoscopic Aluminum Rings
• Energy levels of few electron quantum dots imaged and characterized by atomic force microscopy
• Vortex states in superconducting rings
• Damping of a nanomechanical oscillator strongly coupled to a quantum dot
• Attojoule calorimetry of mesoscopic superconducting loops
• Multiple flux jumps and irreversible behavior of thin Al superconducting rings
• Dilation of the Giant Vortex State in a Mesoscopic Superconducting Loop
• Dynamic transitions between metastable states in a superconducting ring
• Deterministic phase slips in mesoscopic superconducting rings
• Properties of mesoscopic superconducting thin-film rings. London approach
• Fluxoid dynamics in superconducting thin film rings
• Nucleation of superconductivity in a mesoscopic loop of varying width
• Flux transitions in a superconducting ring
• Fluxoid fluctuations in mesoscopic superconducting rings

Cited by in corpus (4)

• Manipulating multi-vortex states in superconducting structures
• Imaging and controlling vortex dynamics in mesoscopic superconductor-normal-metal-superconductor arrays
• Holographic reconstruction of magnetic field distribution in a Josephson junction from diffraction-like Ic(H) patterns
• Phase slip statistics of a single isolated flux-biased superconducting ring