Related Experiment Video
Updated: May 31, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
Andreev reflection and Aharonov-Bohm oscillations through a parallel-coupled double quantum dot with spin-flip
1College of Physics, Hebei Normal University, Shijiazhuang 050016, People's Republic of China. Hebei Advanced Film Laboratory, Shijiazhuang 050016, People's Republic of China.
Summary
This study explores controlling quantum phenomena like Andreev reflection and Aharonov-Bohm oscillations in double quantum dots. Tuning parameters such as spin-flip scattering can suppress oscillations and split Fano peaks.
Area of Science:
- Condensed Matter Physics
- Quantum Computing
Background:
- Quantum dots offer tunable electronic properties for quantum devices.
- Andreev reflection and Aharonov-Bohm oscillations are key quantum phenomena in mesoscopic systems.
Purpose of the Study:
- Investigate Andreev reflection and Aharonov-Bohm oscillations in a parallel-coupled double quantum dot system.
- Explore methods to control these phenomena via system parameters.
Main Methods:
- Utilized nonequilibrium Green's function techniques.
- Analyzed a system comprising a double quantum dot connected to ferromagnetic and superconductor leads.
Main Results:
- Tuning interdot coupling, gate voltage, magnetic flux, and spin-flip scattering influences the quantum phenomena.
- Increased spin-flip scattering suppresses Aharonov-Bohm oscillations and splits Fano resonant peaks.
- Interdot coupling creates distinct strongly and weakly coupled states, with magnetic flux enabling functional swapping.
Conclusions:
- Demonstrated tunability of Andreev reflection and Aharonov-Bohm oscillations in the studied quantum dot system.
- Identified spin-flip scattering and interdot coupling as critical factors for controlling quantum transport.
- The magnetic flux-induced swap effect offers a novel control mechanism for quantum states.
Related Concept Videos
01:12Double Resonance Techniques: Overview
Double resonance techniques in Nuclear Magnetic Resonance (NMR) spectroscopy involve the simultaneous application of two different frequencies or radiofrequency pulses to manipulate and observe two distinct nuclear spins. One important application of double resonance is spin decoupling, which selectively suppresses coupling with one type of nucleus while observing the NMR signal from another nucleus, simplifying the spectrum and enhancing resolution.
Spin decoupling is usually achieved by...
Spin decoupling is usually achieved by...
02:32The de Broglie Wavelength
In the macroscopic world, objects that are large enough to be seen by the naked eye follow the rules of classical physics. A billiard ball moving on a table will behave like a particle; it will continue traveling in a straight line unless it collides with another ball, or it is acted on by some other force, such as friction. The ball has a well-defined position and velocity or well-defined momentum, p = mv, which is defined by mass m and velocity v at any given moment. This is the typical...
01:02¹H NMR: Interpreting Distorted and Overlapping Signals
Spin systems where the difference in chemical shifts of the coupled nuclei is greater than ten times J are called first-order spin systems. These nuclei are weakly coupled, and their chemical shifts and coupling constant can generally be estimated from the well-separated signals in the spectrum.
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
As Δν decreases and the signals move closer, the doublets appear increasingly distorted. The intensities of the inner lines increase at the cost of those of the outer lines as the signals are slanted or...
01:20Spin–Spin Coupling: Two-Bond Coupling (Geminal Coupling)
Two NMR-active nuclei bonded to a central atom can be involved in geminal or two-bond coupling. Geminal coupling is commonly seen between diastereotopic protons in chiral molecules and unsymmetrical alkenes, among others.
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
The central atom need not be NMR-active because its electrons are affected by the electron polarization of the spin-active atoms. However, spin information is transmitted less effectively than in one-bond coupling, and 2J values are usually weaker than 1J values. The energy of...
03:06The Pauli Exclusion Principle
The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that contains three pieces of information:
01:23Atomic Nuclei: Nuclear Relaxation Processes
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis. This...