Related Experiment Video
Updated: May 2, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
10.2K
Parity measurement in topological Josephson junctions.
François Crépin1, Björn Trauzettel1
1Institute for Theoretical Physics and Astrophysics, University of Würzburg, 97074 Würzburg, Germany.
Physical Review Letters
|March 4, 2014
Summary
We investigated topological Josephson junctions, finding their flux periodicity depends on quasiparticle count. Even sectors show 4π periodicity, while odd sectors exhibit 2π periodicity, revealing global parity signatures.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Topological Insulators
Background:
- Topological Josephson junctions utilize the unique properties of topological insulators.
- Understanding fermion parity is crucial for quantum phenomena in these systems.
Purpose of the Study:
- To investigate the impact of fermion parity on the Josephson current in topological Josephson junctions.
- To analyze the relationship between global parity, flux periodicity, and quasiparticle number.
Main Methods:
- Theoretical analysis of topological Josephson junctions.
- Mathematical modeling including bosonization techniques.
- Investigation of Andreev bound states and fermion parity anomaly.
Main Results:
- Global fermion parity clearly influences Josephson current periodicity and critical values.
- Periodicity shifts from 4π (even quasiparticles) to 2π (odd quasiparticles).
- A connection between Andreev bound states and fermion parity anomaly was established for long junctions.
Conclusions:
- Fermion parity pumping significantly impacts topological Josephson junction properties.
- The findings offer insights into controlling and understanding quantum transport in topological materials.
- Coulomb interactions have a quantifiable effect on the Josephson current.
Related Concept Videos
01:27Biasing of Metal-Semiconductor Junctions
907
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...
907
01:16Biasing of P-N Junction
2.7K
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...
2.7K
01:19Equivalent Capacitance
2.0K
Multiple capacitors can be connected in a circuit in series or parallel configuration. When the capacitor combination is connected to a battery, the potential drop across each capacitor and the magnitude of charge stored in the individual capacitor depends on the type of the connection. The capacitor combination is replaced by a single equivalent capacitor that stores the same amount of charge as the combination for a given potential difference.
The following strategies are adopted to calculate...
The following strategies are adopted to calculate...
2.0K
01:19Equivalent Capacitance
939
From the study of resistive circuits, it is understood that employing a series-parallel combination serves as an effective strategy for simplifying circuits. Capacitors can be arranged within a circuit in one of two ways: a series configuration or a parallel configuration. The way these capacitors are connected to a battery will influence both the potential drop across each individual capacitor and the size of the charge that each capacitor can store. This is determined by the specific type of...
939
01:17Second-Order Circuits
4.5K
Integrating two fundamental energy storage elements in electrical circuits results in second-order circuits, encompassing RLC circuits and circuits with dual capacitors or inductors (RC and RL circuits). Second-order circuits are identified by second-order differential equations that link input and output signals.
Input signals typically originate from voltage or current sources, with the output often representing voltage across the capacitor and/or current through the inductor. For example, in...
Input signals typically originate from voltage or current sources, with the output often representing voltage across the capacitor and/or current through the inductor. For example, in...
4.5K
01:11P-N junction
1.7K
A p-n junction is formed when p-type and n-type semiconductor materials are joined together. At the interface of the p-n junction, holes from the p-side and electrons from the n-side begin to diffuse into the opposite sides due to the concentration gradient. This diffusion of carriers leads to a region around the junction where there are no free charge carriers, known as the depletion region. The charge density within the depletion region for the n-side and p-side can be described by the...
1.7K