Related Experiment Video
Updated: Aug 24, 2025
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
9.7K
Josephson Diode Effect in High-Mobility InSb Nanoflags.
Bianca Turini1, Sedighe Salimian1, Matteo Carrega2
1NEST, Istituto Nanoscienze-CNR and Scuola Normale Superiore, 56127Pisa, Italy.
Nano Letters
|October 26, 2022
Summary
Researchers demonstrated Josephson diodes using indium antimonide (InSb) nanoflags, achieving dissipation-less current flow in one direction. This breakthrough in superconducting electronics shows potential for novel device applications.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Superconductivity
Background:
- Superconducting devices offer dissipation-less transport, a key advantage for electronics.
- Josephson junctions are fundamental components in superconducting circuits.
- Achieving directional control of supercurrent, akin to a diode, is a significant challenge.
Purpose of the Study:
- To investigate nonreciprocal transport in single ballistic indium antimonide (InSb) nanoflag Josephson junctions.
- To explore the potential of these junctions as Josephson diodes.
- To understand the underlying physical mechanisms responsible for the observed diode effect.
Main Methods:
- Fabrication of single ballistic InSb nanoflag Josephson junctions.
- Application of in-plane magnetic fields to the junctions.
- Measurement of supercurrent in opposite directions to quantify asymmetry.
- Systematic variation of magnetic field strength, temperature, and carrier concentration.
Main Results:
- Observed nonreciprocal, dissipation-less transport, enabling Josephson diode functionality.
- Supercurrent asymmetry showed a field-dependent behavior: linear increase, saturation, and decrease.
- The effect was maximized when the magnetic field was perpendicular to the current, indicating Rashba spin-orbit coupling's role.
- Supercurrent asymmetry was robust against carrier concentration changes but sensitive to temperature.
Conclusions:
- Single ballistic InSb nanoflag Josephson junctions exhibit intrinsic diode behavior.
- Rashba spin-orbit coupling is identified as the primary mechanism for symmetry breaking.
- These findings pave the way for developing novel superconducting diodes and electronic devices.
Related Concept Videos
01:27Schottky Barrier Diode
444
Schottky barrier diodes are specialized semiconductor devices characterized by their unique construction. This construction involves combining a metal layer with a moderately doped n-type semiconductor material. This combination leads to the formation of a Schottky barrier, a pivotal element that defines the diode's operational characteristics. The core functionality of Schottky barrier diodes is their capacity to allow current to flow in only one direction due to their distinctive...
444
01:27Biasing of Metal-Semiconductor Junctions
313
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
313
01:20Diode: Forward bias
1.2K
In semiconductor devices, diodes play a crucial role in directing current flow, and its operation is primarily categorized into forward bias and reverse bias. A diode is said to be forward-biased when its p-type region is connected to the positive terminal of a battery and its n-type region is linked to the negative terminal. This configuration reduces the potential barrier within the diode, allowing current to flow easily from the p to the n-type region.
The behavior of a diode in forward bias...
The behavior of a diode in forward bias...
1.2K
01:16Biasing of P-N Junction
737
The operation of a p-n junction diode involves various biasing conditions, including forward bias, reverse bias, and equilibrium.
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
737
01:22MOSFET: Enhancement Mode
448
Enhancement-mode MOSFETs are pivotal components in electronics, distinguished by their capacity to act as highly efficient switches. They are part of the larger family of metal-oxide Semiconductor Field-Effect Transistors (MOSFETs). They are available in two types: p-channel and n-channel, each tailored to specific polarity operations.
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no...
In their basic form, enhancement-mode MOSFETs are typically non-conductive when the gate-source voltage (Vgs) is zero. This default 'off' state means no...
448
01:20MOSFET: Depletion Mode
450
Depletion-mode MOSFETs represent a unique subset of MOSFET technology, functioning fundamentally differently from their enhancement-mode counterparts. Unlike enhancement MOSFETs, which require a positive gate-source voltage (Vgs) to turn on, depletion-mode MOSFETs are inherently conductive and "normally on" devices.
The primary characteristic of depletion-mode MOSFETs is their ability to conduct current between the drain and source terminals without gate bias. This inherent conductivity...
The primary characteristic of depletion-mode MOSFETs is their ability to conduct current between the drain and source terminals without gate bias. This inherent conductivity...
450