Related Experiment Video
Updated: Jul 29, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Real-time renormalization group and charge fluctuations in quantum dots
1Forschungszentrum Karlsruhe, Institut fur Nanotechnologie, 76021 Karlsruhe, Germany and Institut fur Theoretische Festkorperphysik, Universitat Karlsruhe, 76128 Karlsruhe, Germany.
Physical Review Letters
|October 6, 2000
Summary
We developed a real-time renormalization-group method to study quantum systems out of equilibrium. This approach accurately calculates conductance in models with electron interactions and environmental effects.
Area of Science:
- Condensed Matter Physics
- Quantum Mechanics
- Statistical Mechanics
Background:
- Describing nonequilibrium properties of quantum systems is challenging.
- Existing methods often struggle with energy broadening, dissipation, and interactions.
Purpose of the Study:
- To develop a real-time, cutoff-independent perturbative renormalization-group (RG) method.
- To apply this method to study the nonequilibrium Anderson impurity model.
Main Methods:
- Perturbative renormalization-group in real time.
- Inclusion of energy broadening and dissipation.
- Development of a cutoff-independent formalism.
Main Results:
- Quantitatively reliable results for linear and nonlinear conductance.
- Analysis of the mixed-valence and empty-orbital regimes.
- Consideration of finite on-site Coulomb repulsion.
Conclusions:
- The developed RG method provides an accurate and versatile tool for nonequilibrium quantum systems.
- The method successfully describes complex phenomena like conductance in interacting impurity models.
More Related Videos
Related Concept Videos
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...
03:08Atomic Radii and Effective Nuclear Charge
The elements in groups of the periodic table exhibit similar chemical behavior. This similarity occurs because the members of a group have the same number and distribution of electrons in their valence shells.
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...
01:17Continuous Charge Distributions
Imagine a bucket of water. It contains many molecules, of the order of 1026 molecules. Thus, although it contains discrete elements (molecules) at the microscopic level, macroscopically, it can be considered continuous. Small volume elements of water, infinitesimal compared to the bulk of the bucket's volume, still contain many molecules. Under this framework, quantized matter is approximated as continuous for practical purposes.
The electric charge can also be subjected to an analogical...
The electric charge can also be subjected to an analogical...
01:22Carrier Generation and Recombination
Carrier generation is the process by which electron-hole pairs (EHPs) are created within the semiconductor. In direct-bandgap semiconductors, such as gallium arsenide (GaAs), this occurs efficiently when energy absorption prompts valence electrons to leap into the conduction band, leaving behind holes.
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
This process is given by the generation rate G and is efficient due to the conservation of momentum between the valence band maximum and conduction band minimum.
Indirect generation involves an...
01:24Electrochemical Systems
Electrochemical systems provide a fascinating insight into the dynamic interplay of charged species within various phases. One notable example is the interaction between a membrane permeable to K⁺ ions but not to Cl⁻ ions, separating an aqueous KCl solution from pure water. As K⁺ ions diffuse through the membrane, they generate net charges on each phase, leading to a potential difference between them.Similarly, when a piece of Zn is immersed in an aqueous ZnSO₄ solution, the Zn metal, composed...