Related Experiment Video
Updated: Jun 14, 2026
10:00
Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Quantum Transition Rates in Arbitrary Physical Processes
Adolfo Del Campo1,2, András Grabarits1, Dmitrii E Makarov3,4
1University of Luxembourg, Department of Physics and Materials Science, L-1511 Luxembourg, Luxembourg.
Physical Review Letters
|June 12, 2026
Summary
We developed a new method to calculate quantum transition rates (QTRs), measuring how fast quantum states change. These rates are limited by fundamental quantum speed limits and can be controlled.
Area of Science:
- Quantum mechanics
- Quantum information theory
- Chemical physics
Background:
- Understanding the dynamics of quantum systems is crucial.
- Quantifying the speed of quantum state evolution is an ongoing challenge.
- Existing methods often struggle with open quantum systems and measurements.
Purpose of the Study:
- Introduce a novel framework for computing time-dependent quantum transition rates (QTRs).
- Describe the pace of quantum state evolution between subspaces.
- Generalize QTRs to open quantum systems and measurements.
Main Methods:
- Expressing QTRs using flux-flux correlators.
- Developing a framework applicable to arbitrary open quantum evolution.
- Utilizing counterdiabatic driving for control.
Main Results:
- QTRs are shown to obey two complementary quantum speed limits.
- The framework successfully generalizes Hamiltonian dynamics.
- Demonstrated control over QTRs via counterdiabatic driving.
Conclusions:
- The proposed framework offers a robust method for calculating QTRs.
- Quantum speed limits are fundamental to quantum state evolution.
- Counterdiabatic driving provides a viable control mechanism for quantum dynamics.
Related Concept Videos
01:25Transition State Theory
Transition-state theory, also known as activated-complex theory, provides a molecular-level explanation of reaction rates in both gas-phase and solution-phase reactions. It extends earlier kinetic models by considering the formation of a short-lived, high-energy configuration during a reaction.The progress of a chemical reaction can be represented using a reaction profile, which plots potential energy against the reaction coordinate. As two reactant molecules approach one another, their...
01:14Atomic Nuclei: Nuclear Spin State Population Distribution
Near absolute zero temperatures, in the presence of a magnetic field, the majority of nuclei prefer the lower energy spin-up state to the higher energy spin-down state. As temperatures increase, the energy from thermal collisions distributes the spins more equally between the two states. The Boltzmann distribution equation gives the ratio of the number of spins predicted in the spin −½ (N−) and spin +½ (N+) states.
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this process,...
01:28Atomic Nuclei: Types of Nuclear Relaxation
Nuclear relaxation restores the equilibrium population imbalance and can occur via spin–lattice or spin–spin mechanisms, which are first-order exponential decay processes.
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...
In spin–lattice or longitudinal relaxation, the excited spins exchange energy with the surrounding lattice as they return to the lower energy level. Among several mechanisms that contribute to spin–lattice relaxation, magnetic dipolar interactions are significant. Here, the excited nucleus transfers energy to a nearby...
03:25Free Energy Changes for Nonstandard States
The free energy change for a process taking place with reactants and products present under nonstandard conditions (pressures other than 1 bar; concentrations other than 1 M) is related to the standard free energy change according to this equation:
01:25Deactivation Processes: Jablonski Diagram
Luminescence, the emission of light by a substance that has absorbed energy, is a process that involves the interaction of molecules with light. The energy-level diagram, or Jablonski diagram, is a graphical representation of these interactions, illustrating the various states and transitions a molecule can undergo. In a typical Jablonski diagram, the lowest horizontal line represents the ground-state energy of the molecule, which is usually a singlet state. This state represents the energies...