A single intrinsic Josephson junction with double-sided fabrication technique

TL;DR

This paper introduces a precise double-sided fabrication technique for creating and controlling the number of intrinsic Josephson junctions in thin Bi-2212 crystals, enabling tailored junction stacks including single junctions.

Contribution

The study presents a novel fabrication method that allows reproducible control over the number of IJJs in a crystal, including the creation of single junctions, which was previously challenging.

Findings

Reproducible fabrication of IJJ stacks with controlled height.

Observation of gap-like features in I-V characteristics.

Ability to produce single junction devices.

Abstract

We make stacks of intrinsic Josephson junctions (IJJs) imbedded in the bulk of very thin ($d\leq 100$~nm) $\mathrm{Bi_2Sr_2CaCu_2O_{8+x}}$ single crystals. By precisely controlling the etching depth during the double-sided fabrication process, the stacks can be reproducibly tailor-made to be of any microscopic height ($0-9 \mathrm{nm} <d$), i.e. enclosing a specified number of IJJ (0-6), including the important case of a single junction. We discuss reproducible gap-like features in the current-voltage characteristics of the samples at high bias.