Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Entropy

Entropy

Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...

Entropy

Entropy

The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...

Third Law of Thermodynamics

Third Law of Thermodynamics

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.

Entropy and the Second Law of Thermodynamics

Entropy and the Second Law of Thermodynamics

The second law of thermodynamics can be stated quantitatively using the concept of entropy. Entropy is the measure of disorder of the system.
The relation between entropy and disorder can be illustrated with the example of the phase change of ice to water. In ice, the molecules are located at specific sites giving a solid state, whereas, in a liquid form, these molecules are much freer to move. The molecular arrangement has therefore become more randomized. Although the change in average...

The Pauli Exclusion Principle

The 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:

Second Law of Thermodynamics

Second Law of Thermodynamics

In the quest to identify a property that may reliably predict the spontaneity of a process, a promising candidate has been identified: entropy. Processes that involve an increase in entropy of the system (ΔS > 0) are very often spontaneous; however, examples to the contrary are plentiful. By expanding consideration of entropy changes to include the surroundings, a significant conclusion regarding the relation between this property and spontaneity may be reached. In thermodynamic models, the...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Refined Density Functional Theory Recipe and Renormalization of Band-Edge Parameters for Electrons in Monolayer MoS<sub>2</sub> Informed by the Measured Spin-Orbit Splitting.

Nano letters·2026

Same author

Time-Resolved Charge Detection in Transition Metal Dichalcogenide Quantum Dots.

Nano letters·2026

Same author

Tunable high-efficiency microwave photon detector based on a double quantum dot coupled to a superconducting high-impedance cavity.

Science advances·2026

Same author

40 Tesla miniature magnets.

Science advances·2026

Same author

Longitudinal analysis of psychometric properties of the Seattle Angina Questionnaire among patients who underwent coronary artery bypass grafting in Serbia.

Population health metrics·2025

Same author

Experimental detection of vortices in magic-angle graphene.

Nature communications·2025

Same journal

Erratum: Spectroscopy and Ground-State Transfer of Ultracold Bosonic ^{39}K^{133}Cs Molecules [Phys. Rev. Lett. 135, 203401 (2025)].

Physical review letters·2026

Same journal

Erratum: Lifetime of the ^{2}F_{7/2} Level in Yb^{+} for Spontaneous Emission of Electric Octupole Radiation [Phys. Rev. Lett. 127, 213001 (2021)].

Physical review letters·2026

Same journal

Laser-Plasma Based Seeded Free Electron Laser in the High-Gain Regime.

Physical review letters·2026

Same journal

Parent Hamiltonians for Stabilizer Quantum Many-Body Scars.

Physical review letters·2026

Same journal

Properties of Heavy Cosmic Nuclei Phosphorus, Chlorine, Argon, Potassium, and Calcium: Results from the Alpha Magnetic Spectrometer.

Physical review letters·2026

Same journal

Role of Spin-Isospin Symmetries in Nuclear β-Decays.

Physical review letters·2026

See all related articles

Search research articles

Related Experiment Video

Updated: Jan 9, 2026

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection

Published on: October 13, 2017

Entropy of a Double Quantum Dot.

David Kealhofer¹, Christoph Adam¹, Max J Ruckriegel¹

¹ETH Zürich, Laboratory for Solid State Physics, CH-8093 Zürich, Switzerland.

Physical Review Letters

|November 30, 2025

Summary

This summary is machine-generated.

Researchers measured entropy changes in a double quantum dot system. They found single electron occupation increases entropy, and analyzed molecular regimes and Pauli blockade effects.

More Related Videos

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Published on: November 1, 2013

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

Published on: June 28, 2016

Related Experiment Videos

Last Updated: Jan 9, 2026

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection

Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection

Published on: October 13, 2017

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots

Published on: November 1, 2013

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

Published on: June 28, 2016

Area of Science:

Quantum physics
Condensed matter physics

Background:

Double quantum dots are tunable systems with applications in quantum computing.
Understanding entropy in quantum systems is crucial for developing quantum technologies.

Purpose of the Study:

To detect and analyze entropy changes in a double quantum dot system.
To investigate entropy in both separated (artificial atom) and coupled (molecule-like) regimes.
To understand the impact of charge transitions and Pauli blockade on entropy measurements.

Main Methods:

Utilizing charge sensing techniques to measure entropy.
Configuring a GaAs/AlGaAs heterostructure into a double quantum dot via electrostatic gating.
Employing a rate equation model to analyze non-equilibrium effects.

Main Results:

Confirmed that single electron occupation of a quantum dot increases entropy by k_{B}log2.
Characterized entropy changes across two distinct charge transitions in the molecular regime.
Identified Pauli blockade as a confounding factor in entropy signals and demonstrated its non-equilibrium origin.

Conclusions:

The study provides a foundational understanding of entropy in the simplest coupled quantum system.
This work paves the way for studying entropy in more complex quantum systems, including those with topological or entangled states.
The developed methods allow for the exclusion of non-equilibrium artifacts from entropy analysis.