Microwave-induced constant voltage steps in surface junctions of Bi_{2}Sr_{2}CaCu_{2}O_{8+\delta} single crystals

TL;DR

This study reports the observation of microwave-induced voltage steps in a surface junction of Bi-2212 single crystals, demonstrating the ac Josephson effect and Bessel-function behavior in the voltage steps.

Contribution

First demonstration of microwave-induced zero-crossing voltage steps in surface junctions of Bi-2212 single crystals, confirming intrinsic Josephson junction behavior.

Findings

Voltage steps satisfy the ac Josephson relation.

Step heights follow Bessel-function behavior with microwave power.

Intrinsic surface junctions meet criteria for zero-crossing steps.

Abstract

We have observed the zero-crossing steps in a surface junction of a mesa structure micro-fabricated on the surface of a Bi-2212 single crystal. With the application of microwave of frequencies 76 and 94 GHz, the current-voltage characteristics show clear voltage steps satisfying the ac Josephson relation. Increasing the microwave power, the heights of the steps show the Bessel-function behavior up to step number n=4. We confirm that the intrinsic surface junction meets the criterion for the observation of zero-crossing steps.