Related Experiment Video
Updated: Mar 14, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
9.0K
Thermodynamics versus Local Density Fluctuations in the Metal-Mott-Insulator Crossover.
J H Drewes1, E Cocchi1,2, L A Miller1,2
1Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany.
Physical Review Letters
|October 8, 2016
Summary
Researchers explored the metal-Mott insulator transition in fermionic atoms. The study found that in the metallic phase, local measurements don
Area of Science:
- Condensed matter physics
- Quantum simulation
- Ultracold atomic gases
Background:
- The transition between metallic and Mott insulating states is a fundamental phenomenon in condensed matter physics.
- Understanding fermion localization is key to characterizing quantum phases of matter.
- Optical lattices provide a controllable platform for simulating complex quantum systems.
Purpose of the Study:
- To experimentally investigate the crossover between metallic and Mott insulator phases in fermionic atoms.
- To probe the validity of the local fluctuation-dissipation theorem across this transition.
- To differentiate between local and thermodynamic correlations in different quantum regimes.
Main Methods:
- Utilizing fermionic atoms loaded into an optical lattice.
- Performing measurements of thermodynamic and local (on-site) density correlations.
- Analyzing the behavior of the fluctuation-dissipation theorem.
Main Results:
- Observed violation of the local fluctuation-dissipation theorem in the metallic phase, indicating non-local effects on thermodynamics.
- Demonstrated convergence of local and thermodynamic fluctuations in the Mott insulator phase.
- Showcased the absence of long-range density-density correlations in the Mott insulator.
Conclusions:
- The study highlights the limitations of local observables in characterizing metallic phases near the Mott transition.
- Confirms that Mott insulators exhibit local correlations that align with thermodynamic properties.
- Provides experimental insights into fermion localization and quantum phase transitions in optical lattice systems.
Related Concept Videos
01:17Theory of Metallic Conduction
1.9K
The conduction of free electrons inside a conductor is best described by quantum mechanics. However, a classical model makes predictions close to the results of quantum mechanics. It is called the theory of metallic conduction.
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
In this theory, Newton's second law of motion is used to determine the acceleration of an electron in the presence of an applied electric field. Then, its velocity is expressed via this acceleration.
An electron moves through the crystal, containing positive ions,...
1.9K
01:25Boundary Conditions for Current Density
1.4K
Current density becomes discontinuous across an interface of materials with different electrical conductivities. The normal component of the current density is continuous across the boundary.
1.4K
02:38Third Law of Thermodynamics
22.6K
A pure, perfectly crystalline solid possessing no kinetic energy (that is, at a temperature of absolute zero, 0 K) may be described by a single microstate, as its purity, perfect crystallinity,and complete lack of motion means there is but one possible location for each identical atom or molecule comprising the crystal (W = 1). According to the Boltzmann equation, the entropy of this system is zero.
22.6K
02:39Phase Transitions: Melting and Freezing
15.5K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
15.5K
02:32Bonding in Metals
55.3K
Metallic bonds are formed between two metal atoms. A simplified model to describe metallic bonding has been developed by Paul Drüde called the “Electron Sea Model”.
55.3K
01:21Current Density
5.4K
The total amount of current flowing through one unit value of a cross-sectional area is referred to as current density. If the current flow is uniform, the amount of current flowing through a conductor is the same at all points along the conductor, even if the conductor area varies. The current density consists of the local magnitude and direction of the charge flow, which varies from point to point. Current density is measured in amperes per meter square, and direction is defined as the net...
5.4K