Near-field induced FIR Josephson-detection by c-axis-oriented YBa_2Cu_3O_7-delta-films

TL;DR

This paper presents a new method for detecting far-infrared radiation using c-axis oriented YBa2Cu3O7-delta films, exploiting near-field effects at electric contacts to induce Josephson detection signals.

Contribution

It introduces a novel near-field detection technique for FIR radiation leveraging c-axis oriented superconducting films and contact geometry effects.

Findings

Detection of Josephson signals via near-zone field effects.

Wavelength-independent fast signals observed at contact edges.

Differentiation between bolometric and Josephson detection signals.

Abstract

A novel approach to intrinsic Josephson-detection of far infrared radiation is reported utilizing near-zone field effects at electric contacts on c-axis oriented YBa_2Cu_3O_7-delta films. While only a bolometric signal was observed focusing the radiation far off the contacts on c-axis normal films, irradiating the edge of contacts yielded an almost wavelength independent fast signal showing the characteristic intensity dependence of Josephson-detection. The signal is attributed to a c-axis parallel component of the electric radiation field being generated in the near-zone field of diffraction at the metallic contact structures.