The Josephson Plasma Resonance in Bi_2Sr_2CaCu_2O_8 in a Tilted Field

TL;DR

This paper investigates how the Josephson plasma frequency in Bi_2Sr_2CaCu_2O_8 varies with magnetic field orientation, providing experimental validation and refinement of theoretical models, and extracting key physical parameters.

Contribution

It offers a detailed comparison between experimental measurements and a modified theoretical model for Josephson plasma resonance in a tilted magnetic field.

Findings

Close agreement between experiment and theory after model modification

Determined in-plane correlation length and critical current density

Described an analogy to Bragg diffraction and fractional-exponent behavior

Abstract

The dependence of the Josephson plasma frequency omega_p in Bi_2Sr_2CaCu_2O_8 on a tilted field H is reported. Measurements over a large range of B and tilt angle theta allow a detailed comparison with a recent calculation by Koshelev. With a slight modification of the model, close agreement is obtained. From the fits, we find values for the in-plane correlation length and the zero-field critical current density J_{c0} (4,600 A/cm^2 at 30 K). An analogy to Bragg diffraction is described, as well as a picture for the fractional-exponent behavior of omega_p versus H.