Related Experiment Video
Updated: May 29, 2025
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
14.4K
Role of Quantum Coherence in Kinetic Uncertainty Relations.
Kacper Prech1, Patrick P Potts1, Gabriel T Landi2
1University of Basel, Department of Physics and Swiss Nanoscience Institute, Klingelbergstrasse 82, 4056 Basel, Switzerland.
Physical Review Letters
|February 6, 2025
Summary
Quantum coherence can violate the kinetic uncertainty relation (KUR). This study derives a new bound, clarifying how quantum effects impact signal-to-noise ratios in stochastic currents and revealing differences between quantum jumps and diffusion.
Area of Science:
- Quantum thermodynamics
- Mesoscopic physics
- Statistical mechanics
Background:
- The kinetic uncertainty relation (KUR) establishes a fundamental limit on the signal-to-noise ratio of stochastic currents, related to dynamical activity.
- Classical KUR can be violated in quantum systems due to quantum coherence, but the exact mechanism remains unclear.
Purpose of the Study:
- To derive a modified kinetic uncertainty relation that precisely describes how quantum coherence leads to KUR violations.
- To investigate the influence of different quantum measurement unravellings (quantum jumps vs. quantum diffusion) on KUR violations.
Main Methods:
- Derivation of a novel, coherence-sensitive kinetic uncertainty relation.
- Analysis of quantum master equations and their different unraveling schemes.
- Application of the derived bound to a double quantum dot system.
Main Results:
- A new bound is derived that quantifies the impact of quantum coherence on KUR.
- The bound's sensitivity to the choice of quantum master equation unraveling is demonstrated.
- Distinct effects of quantum jumps and quantum diffusion on fluctuations are elucidated.
Conclusions:
- Quantum coherence can indeed lead to violations of the kinetic uncertainty relation.
- The specific method of quantum measurement (unraveling) critically determines how coherence affects fluctuations.
- This work provides a theoretical framework for understanding quantum effects on fundamental thermodynamic relations.
Related Concept Videos
04:08The Uncertainty Principle
23.0K
Werner Heisenberg considered the limits of how accurately one can measure properties of an electron or other microscopic particles. He determined that there is a fundamental limit to how accurately one can measure both a particle’s position and its momentum simultaneously. The more accurate the measurement of the momentum of a particle is known, the less accurate the position at that time is known and vice versa. This is what is now called the Heisenberg uncertainty principle. He...
23.0K
02:45The Quantum-Mechanical Model of an Atom
41.8K
Shortly after de Broglie published his ideas that the electron in a hydrogen atom could be better thought of as being a circular standing wave instead of a particle moving in quantized circular orbits, Erwin Schrödinger extended de Broglie’s work by deriving what is now known as the Schrödinger equation. When Schrödinger applied his equation to hydrogen-like atoms, he was able to reproduce Bohr’s expression for the energy and, thus, the Rydberg formula governing hydrogen spectra.
41.8K
02:32The de Broglie Wavelength
25.3K
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...
25.3K
03:06The Pauli Exclusion Principle
34.6K
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:
34.6K
00:59Propagation of Uncertainty from Random Error
632
An experiment often consists of more than a single step. In this case, measurements at each step give rise to uncertainty. Because the measurements occur in successive steps, the uncertainty in one step necessarily contributes to that in the subsequent step. As we perform statistical analysis on these types of experiments, we must learn to account for the propagation of uncertainty from one step to the next. The propagation of uncertainty depends on the type of arithmetic operation performed on...
632
02:43Basic Postulates of Kinetic Molecular Theory: Particle Size, Energy, and Collision
33.6K
The ideal-gas equation, which is empirical, describes the behavior of gases by establishing relationships between their macroscopic properties. For example, Charles’ law states that volume and temperature are directly related. Gases, therefore, expand when heated at constant pressure. Although gas laws explain how the macroscopic properties change relative to one another, it does not explain the rationale behind it.
33.6K