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

Journal of Southwest China Normal University

Quantum Coherence of Interaction Between Two-level Atom and Electromagnetic Field

Zhihong Wang

Published Jan 1, 2010• 0 citations
OpenAlex

Abstract

Quantum coherence of two-level atom in a certain circumstance is discused by the method of density matrix.Hamitonian operator of two-level atom in classic electromagnetic field is expressed by atomic operators;based on Schdinger equation,the evolution equations of density matrix in two-level atomic system is gained;by solving the evolution equations,the detailed density matrix in such a system is derived.It is obtained that the pure state system can retain nicer quantum coherence.

Related papers

Quantum coherence of two-level atom in the electromagnetism field

Gao Feng

We have found out the equation of density matrix evolution of the two-level atomic system in the classic electromagnetism field. The Law of coherence of the state is obtained.

Chinese journal of atomic and molecular physics•Jan 1, 2004•0 citations

Density Matrix of Two-level Atom in the Electromagnetism Field

Feng Gao

We have figured the equation of density matrix evolution of the twolevel atomic system in the classic electromagnetism field.The regular which evolution of the state is obtained.

Journal of Hengyang Normal University•Jan 1, 2003•0 citations

Quantum Coherence of the state of disintegratin two-level atom in the electromagnetism field

Gao Feng

Using a two-level atom as a quantum bit,We have figured the equatio n of density matrix evolution of the disintegratin two-level atomic system in the cl assic electromagnetism field. The quantum coherenct properties in evolution of the st ate as follows time is obtained.

Chinese journal of atomic and molecular physics•Jan 1, 2005•0 citations

Evolution of the State of Disintegrating two-level Atom in the Electromagnetical Field

Zhang Deng

Using a two-level atom as a quantum bit,We have figured the equation of density matrix evolution of the disintegrating two-level atomic system in the classic electromagnetcal field.As a result we get the evolution rule.

Journal of Hengyang Normal University•Jan 1, 2005•0 citations

Evolution of the state of two-level without disintegratin in the electromagnetism field

Gao Feng

We have figured the equation of density matrix evolution of the two-level atomic system in the classic electromagnetism field. The evolutional regular of the state is obtained.

Chinese journal of atomic and molecular physics•Jan 1, 2003•0 citations

Quantum Mechanics of Atomic Response

Surendra Singh

In this chapter a quantum mechanical treatment of atomic response to the fields of an electromagnetic wave is presented. Absorption and emission of energy by atoms involves transition between their quantized energy levels driven by an interaction Hamiltonian. Schrodinger equation is used to derive the equations of motion for the density matrix of the atom, which is better suited to include the effects of mechanisms other than the interaction Hamiltonian – collisions, level decays, level shifts, etc. that also affect the state of the atom. Using the density matrix equation of motion and focusing on two atomic levels, induced dipole moment for a single two-level atom and polarization and susceptibility for a collection of two-level atoms, including the effects of level decays, and collisions, are calculated. Equations of motion for level populations are also derived. These expressions naturally predict stimulated emission as well as absorption. Expressed in terms of spontaneous emission rate they confirm the validity of equations derived in Chapter 5 using the dipole oscillator model of atomic response. The limit in which quantum mechanical equations for atomic response reduce to the classical dipole oscillator equations is also discussed.

CRC Press eBooks•Sep 23, 2026•0 citations
Quantum coherence of two-level atom in a certain circumstance is discused by the method of density matrix.Hamitonian operator of two-level atom in classic electromagnetic field is expressed by atomic operators;based on Schdinger equation,the evolution equations of density matrix in two-level atomic system is gained;by solving the evolution equations,the detailed density matrix in such a system is derived.It is obtained that the pure state system can retain nicer quantum coherence.
In this chapter a quantum mechanical treatment of atomic response to the fields of an electromagnetic wave is presented. Absorption and emission of energy by atoms involves transition between their quantized energy levels driven by an interaction Hamiltonian. Schrodinger equation is used to derive the equations of motion for the density matrix of the atom, which is better suited to include the effects of mechanisms other than the interaction Hamiltonian – collisions, level decays, level shifts, etc. that also affect the state of the atom. Using the density matrix equation of motion and focusing on two atomic levels, induced dipole moment for a single two-level atom and polarization and susceptibility for a collection of two-level atoms, including the effects of level decays, and collisions, are calculated. Equations of motion for level populations are also derived. These expressions naturally predict stimulated emission as well as absorption. Expressed in terms of spontaneous emission rate they confirm the validity of equations derived in Chapter 5 using the dipole oscillator model of atomic response. The limit in which quantum mechanical equations for atomic response reduce to the classical dipole oscillator equations is also discussed.