Related Experiment Video
Updated: Nov 4, 2025
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
9.9K
Subgap dynamics of double quantum dot coupled between superconducting and normal leads.
B Baran1, R Taranko2, T Domański3
1Institute of Physics, M. Curie-Skłodowska University, 20-031, Lublin, Poland. bartlobaran@kft.umcs.lublin.pl.
Scientific Reports
|May 28, 2021
Summary
Investigating dynamical processes in a nanoscopic heterostructure reveals rich spectral features. These findings offer insights into superconducting qubit design by analyzing quasiparticle dynamics.
Area of Science:
- Condensed Matter Physics
- Quantum Computing
Background:
- Dynamical processes driven by external fields reveal system energy scales.
- Nanoscopic heterostructures with quantum dots are crucial for quantum technologies.
Purpose of the Study:
- Investigate dynamical processes in a double quantum dot heterostructure.
- Analyze the system's response to time-dependent fields and energy level changes.
- Explore subgap properties related to quasiparticles and their signatures in charge currents.
Main Methods:
- Studying a nanoscopic heterostructure: double quantum dot coupled to superconducting and metallic reservoirs.
- Applying external time-dependent fields: abrupt bias voltage, sudden energy level changes, and periodic driving.
- Analyzing time-dependent charge currents and subgap properties.
Main Results:
- Observed multi-mode oscillations and beating patterns in charge currents.
- Identified photon-assisted harmonics indicating rich dynamical features.
- Linked subgap properties to in-gap quasiparticle signatures.
Conclusions:
- Dynamical responses provide insight into characteristic energy scales.
- Observed spectral features are relevant for designing superconducting qubits.
- The study highlights the potential of nanoscopic heterostructures in quantum information processing.
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