Interactions and Mobility Edges: Observing the Generalized Aubry-André Model.
Fangzhao Alex An1, Karmela Padavić1, Eric J Meier1
1Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801-3080, USA.
Physical Review Letters
|February 12, 2021
Summary
Researchers experimentally realized a novel tight-binding model with a protected mobility edge. Attractive interactions significantly altered electron localization, deviating from single-particle predictions.
Area of Science:
- Quantum physics
- Condensed matter physics
- Atomic physics
Background:
- Nearest-neighbor tight-binding models are crucial for understanding electron behavior in materials.
- Quasiperiodic potentials and duality symmetries can lead to unique electronic properties, including mobility edges.
- The Aubry-André model is a foundational example of a system exhibiting a mobility edge.
Purpose of the Study:
- To experimentally realize and investigate a generalized tight-binding model with quasiperiodic site energy modulation.
- To explore the existence and properties of an exact mobility edge protected by duality symmetry.
- To study the influence of inter-particle interactions on localization phenomena in such systems.
Main Methods:
- Utilizing synthetic lattices of laser-coupled atomic momentum modes to create the model system.
- Adiabatically preparing low and high energy eigenstates.
- Performing microscopic measurements of participation ratios to track mobility edge evolution.
Main Results:
- Experimental realization of a tight-binding model with a duality-protected mobility edge.
- Observation of energy-dependent density of states modification by a tuning parameter.
- Significant deviations from single-particle predictions due to attractive interactions, showing enhanced localization at low energies and inhibited localization at high energies.
Conclusions:
- Attractive interactions play a crucial role in modifying localization in systems with duality-induced mobility edges.
- Observed self-trapping and screening effects highlight the importance of interactions beyond single-particle descriptions.
- This work provides a platform for future quantitative studies of interaction effects on mobility edges.
Related Concept Videos
01:14Multicompartment Models: Overview
357
Multicompartment models are mathematical constructs that depict how drugs are distributed and eliminated within the body. They segment the body into several compartments, symbolizing various physiological or anatomical areas connected through drug transfer processes such as absorption, metabolism, distribution, and elimination.
These models offer a more comprehensive representation of drug behavior in the body than one-compartment models. They accommodate the complexity of drug distribution,...
These models offer a more comprehensive representation of drug behavior in the body than one-compartment models. They accommodate the complexity of drug distribution,...
357
01:09Theories of Dissolution: The Danckwerts' Model and Interfacial Barrier Model
590
Various dissolution theories provide insight into the factors that influence the dissolution rate. Danckwerts' Model suggests that turbulence, rather than a stagnant layer, characterizes the dissolution medium at the solid-liquid interface. In this model, the agitated solvent contains macroscopic packets that move to the interface via eddy currents, facilitating the absorption and delivery of the drug to the bulk solution. The regular replenishment of solvent packets maintains the...
590
01:34Woodward–Hoffmann Selection Rules and Microscopic Reversibility
3.5K
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...
3.5K
01:23Mechanistic Models: Compartment Models in Individual and Population Analysis
151
Mechanistic models are utilized in individual analysis using single-source data, but imperfections arise due to data collection errors, preventing perfect prediction of observed data. The mathematical equation involves known values (Xi), observed concentrations (Ci), measurement errors (εi), model parameters (ϕj), and the related function (ƒi) for i number of values. Different least-squares metrics quantify differences between predicted and observed values. The ordinary least...
151
01:21Mechanistic Models: Overview of Compartment Models
247
Mechanistic models, a category encompassing both physiological and compartmental modeling, differ from empirical models' approaches to incorporating known factors about the systems being modeled. Empirical models describe data with minimal assumptions, while mechanistic models aim to provide a robust description of available data by specifying assumptions and integrating known factors about the system. Compartmental analysis is a key example of a mechanistic model in pharmacokinetics and...
247
01:13Parameters Affecting Nonlinear Elimination: Zero-Order Input, First-Order Absorption and Two-Compartment Model
179
Drugs administered through various routes can lead to nonlinear elimination, resulting in complex pharmacokinetic behaviors crucial to understanding efficacious drug dosing.
When a drug is administered through a constant intravenous infusion and eliminated via nonlinear pharmacokinetics, it follows zero-order input. For example, oral drugs undergo first-order absorption upon administration and are eliminated through nonlinear pharmacokinetics.
In the case of subcutaneously administered drugs,...
When a drug is administered through a constant intravenous infusion and eliminated via nonlinear pharmacokinetics, it follows zero-order input. For example, oral drugs undergo first-order absorption upon administration and are eliminated through nonlinear pharmacokinetics.
In the case of subcutaneously administered drugs,...
179