Demonstration of dual Shapiro steps in small Josephson junctions

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Kaap, Fabian, Kissling, Christoph, Gaydamachenko, Victor, Grünhaupt, Lukas, Lotkhov, Sergey
Format: Preprint
Published: 2024
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912063424561152
author Kaap, Fabian
Kissling, Christoph
Gaydamachenko, Victor
Grünhaupt, Lukas
Lotkhov, Sergey
author_facet Kaap, Fabian
Kissling, Christoph
Gaydamachenko, Victor
Grünhaupt, Lukas
Lotkhov, Sergey
contents Bloch oscillations in small Josephson junctions were predicted theoretically as the quantum dual to Josephson oscillations. A significant consequence of this prediction is the emergence of quantized current steps, so-called dual Shapiro steps, when synchronizing Bloch oscillations to an external microwave signal. These steps potentially enable a fundamental standard of current $I$, defined via the frequency $f$ of the external signal and the elementary charge $e$, $I=\pm n \times 2ef$, where $n$ is a natural number. Here, we realize this fundamental relation by synchronizing the Bloch oscillations in small Al/AlO$_\mathrm{x}$/Al Josephson junctions to sinusoidal drives with frequencies varying from $1$ to $6\:\mathrm{GHz}$ and observe dual Shapiro steps up to $I\approx 3 \: \mathrm{nA}$. Inspired by today's voltage standards and to further confirm the duality relation, we investigate a pulsed drive regime, which is dual to the single flux quantum mode of Josephson oscillations, and observe a similar asymmetric pattern of dual Shapiro steps. This work confirms quantum duality effects in Josephson junctions and paves the way towards a range of applications in quantum metrology based on well-established fabrication techniques and straightforward circuit design.
format Preprint
id arxiv_https___arxiv_org_abs_2401_06599
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Demonstration of dual Shapiro steps in small Josephson junctions
Kaap, Fabian
Kissling, Christoph
Gaydamachenko, Victor
Grünhaupt, Lukas
Lotkhov, Sergey
Mesoscale and Nanoscale Physics
Superconductivity
Quantum Physics
Bloch oscillations in small Josephson junctions were predicted theoretically as the quantum dual to Josephson oscillations. A significant consequence of this prediction is the emergence of quantized current steps, so-called dual Shapiro steps, when synchronizing Bloch oscillations to an external microwave signal. These steps potentially enable a fundamental standard of current $I$, defined via the frequency $f$ of the external signal and the elementary charge $e$, $I=\pm n \times 2ef$, where $n$ is a natural number. Here, we realize this fundamental relation by synchronizing the Bloch oscillations in small Al/AlO$_\mathrm{x}$/Al Josephson junctions to sinusoidal drives with frequencies varying from $1$ to $6\:\mathrm{GHz}$ and observe dual Shapiro steps up to $I\approx 3 \: \mathrm{nA}$. Inspired by today's voltage standards and to further confirm the duality relation, we investigate a pulsed drive regime, which is dual to the single flux quantum mode of Josephson oscillations, and observe a similar asymmetric pattern of dual Shapiro steps. This work confirms quantum duality effects in Josephson junctions and paves the way towards a range of applications in quantum metrology based on well-established fabrication techniques and straightforward circuit design.
title Demonstration of dual Shapiro steps in small Josephson junctions
topic Mesoscale and Nanoscale Physics
Superconductivity
Quantum Physics
url https://arxiv.org/abs/2401.06599