Magnetic field induced 3D to 1D crossover in Sr0:9La0:1CuO2

TL;DR

This paper investigates how magnetic fields induce a dimensional crossover in Sr0.9La0.1CuO2, revealing a transition from three-dimensional to one-dimensional superconductivity due to finite size effects, challenging mean-field predictions.

Contribution

It provides experimental evidence for a magnetic field induced 3D to 1D crossover in a high-temperature superconductor using scaling theory and magnetization data.

Findings

Identification of a magnetic field induced finite size effect.

Evidence for a 3D to 1D crossover line Hpi(T).

Superconductivity confined to cylinders above Hpi(T).

Abstract

The effect of the magnetic field on the critical behavior of Sr0:9La0:1CuO2 is explored in terms of reversible magnetization data. As the correlation length transverse to the magnetic field Hi,applied along the i-axis, cannot grow beyond the limiting magnetic length LHi, related to the average distance between vortex lines, one expects a magnetic field induced finite size effect. Invoking the scaling theory of critical phenomena we provide clear evidence for this effect. It implies that in type II superconductors there is a 3D to 1D crossover line Hpi(T). Consequently, below Tc and above Hpi(T) uperconductivity is confined to cylinders with diameter LHi(1D). Accordingly, there is no continuous phase transition in the (H,T)-plane along the Hc2-lines as predicted by the mean-field treatment.