Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Nonadiabatic transitions and decoherence

Nikolai A. Sinitsyn, Valery Pokrovsky

Published Feb 5, 2026• 0 citations
Publisher

Abstract

Abstract This chapter introduces the methods for estimating nonadiabatic transition probabilities at presence of environment. The role of Zeno effect and noise are discussed. Applications to nanomagnets and measurements of their small tunnelling gap is the main practical example.
DOI
10.1093/oso/9780198988007.003.0008

Related papers

Generalizations of the Landau-Zener theory in the physics of nanoscale systems

Nikolai A. Sinitsyn

Nanoscale systems have sizes intermediate between atomic and macroscopic ones. Therefore their treatment often requires a combination of methods from atomic and condensed matter physics. The conventional Landau-Zener theory, being a powerful tool in atomic physics, often fails to predict correctly nonadiabatic transition probabilities in various nanostructures because it does not include many-body effects typical for mesoscopics. In this research project the generalizations of the Landau-Zener theory that solve this problem were studied. The multistate, multiparticle and nonunitary extensions of the theory have been proposed and investigated. New classes of exactly solvable models have been derived. I discuss their applications in problems of the molecular condensate dissociation and of the driven charge transport. In application to the physics of nanomagnets new approaches in modeling the influence of the environment on the Landau-Zener evolution are proposed and simple universal formulas are derived for the extensions of the theory that include the coupling to noise and the nuclear spin bath.

•Sep 30, 2004•6 citations

Quantum Zeno Subspaces

Paolo Facchi A, Saverio Pascazio

The quantum Zeno effect is recast in terms of an adiabatic theorem when the measurement is described as the dynamical coupling to another quantum system that plays the role of apparatus. A few significant examples are proposed and their practical relevance discussed. We also focus on decoherence-free subspaces.

arXiv:quant-ph/0201115•Physical Review Letters•Aug 6, 2002•550 citations

On the Quantum Zeno Effect and Time Series Related to Quantum Measurements

Karl‐Heinz Fichtner, Kei Inoue

Our main aim is to prove a more general version of the quantum Zeno effect. Then we discuss some examples of the quantum Zeno effect. Furthermore, we discuss a possibility that based on the quantum Zeno effect and certain experiments one could check whether, from the statistical point of view, a concrete system behaves like a quantum system. The more general version of quantum Zeno effect can be helpful to prove that the brain acts like in a quantum system. The proof of our main result is based on certain formulas describing probability distributions of time series related to quantum measurements.

Applied Mathematics•Jan 1, 2013•1 citation

1 Quantum Zeno dynamics and quantum Zeno subspaces ∗

Paolo Facchi A, Saverio Pascazio C

A quantum Zeno dynamics can be obtained by means of frequent measurements, frequent unitary kicks or a strong continuous coupling and yields a partition of the total Hilbert space into quantum Zeno subspaces, among which any transition is hindered. We focus on the “continuous ” version of the quantum Zeno effect and look at several interesting examples. We first analyze these examples in practical terms, towards applications, then propose a novel experiment. 1

•Jan 1, 2009•62 citations

Noise Effect on the Nonadiabatic Transition in the System of Fe8

Masamichi Nishino, Keiji Saito, Seiji Miyashita

We study the effect of noise on the tunnel splitting in the system of Fe8. The tunnel gap between the lowest two states is estimated making use of the Landau-Zener-Stückelberg (LZS) formula. We consider how the estimated gap deviates from the true tunneling gap. We also study the difference of the effect of noise between the systems of S=1/2 and S=10 and discuss the relation to the experimental results.

Progress of Theoretical Physics Supplement•Jan 1, 2002•0 citations

Model study of the Landau–Zener approximation

S. Geltman, Nathan D. Aragon

We reexamine the accuracy of the Landau–Zener approximation, whose analytic simplicity has made it often cited and applied over the past 70years in describing nonadiabatic transitions. We find that this approximation may be in substantial disagreement with exact numerical results for a model physical system and a wide range of coupling strengths and relative velocities. We conclude that the Landau–Zener approximation should be used with caution for quantitative estimates of nonadiabatic transition probabilities or cross sections.

American Journal of Physics•Oct 18, 2005•3 citations
Nanoscale systems have sizes intermediate between atomic and macroscopic ones. Therefore their treatment often requires a combination of methods from atomic and condensed matter physics. The conventional Landau-Zener theory, being a powerful tool in atomic physics, often fails to predict correctly nonadiabatic transition probabilities in various nanostructures because it does not include many-body effects typical for mesoscopics. In this research project the generalizations of the Landau-Zener theory that solve this problem were studied. The multistate, multiparticle and nonunitary extensions of the theory have been proposed and investigated. New classes of exactly solvable models have been derived. I discuss their applications in problems of the molecular condensate dissociation and of the driven charge transport. In application to the physics of nanomagnets new approaches in modeling the influence of the environment on the Landau-Zener evolution are proposed and simple universal formulas are derived for the extensions of the theory that include the coupling to noise and the nuclear spin bath.
Our main aim is to prove a more general version of the quantum Zeno effect. Then we discuss some examples of the quantum Zeno effect. Furthermore, we discuss a possibility that based on the quantum Zeno effect and certain experiments one could check whether, from the statistical point of view, a concrete system behaves like a quantum system. The more general version of quantum Zeno effect can be helpful to prove that the brain acts like in a quantum system. The proof of our main result is based on certain formulas describing probability distributions of time series related to quantum measurements.
We reexamine the accuracy of the Landau–Zener approximation, whose analytic simplicity has made it often cited and applied over the past 70years in describing nonadiabatic transitions. We find that this approximation may be in substantial disagreement with exact numerical results for a model physical system and a wide range of coupling strengths and relative velocities. We conclude that the Landau–Zener approximation should be used with caution for quantitative estimates of nonadiabatic transition probabilities or cross sections.