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

Jiguang zazhi

Utilizing Kraus operator to analysis the transformation of density matrix of particles of ruby laser

Tang Zhi

Published Jan 1, 2005• 0 citations
OpenAlex

Abstract

Ruby laser is a three-level system.This paper utilizes theories of Kraus operator,to analysis the three-level system which is in the case of absorption as well as radiation .The object of the research is to probe into the transformation properties of density matrix.The result show that when particles transform from ground state to the second excitated state and from the second excitated state to the first excitated state at very high probability,the system forms reversion of particles and prepares for producing laser.It also show that when particles transform from the first excitated state to the ground state at very high probability,the system produces laser.

Related papers

The transformation of density matrix of four-level system in solid laser

Tang Mei-juan

Solid laser is a four-level system.This paper utilizes theories of quantum mechanics and Kraus operator,to analysis the four-level system which in the case of absorption as well as radiation.The object of the research is to probe into the transformation properties of density matrix.The result shows that probability of absorption and radiation condition is satisfied,between the second excited state and the first excited state forms reversion of particles and prepares for producing laser.It also shows that when particles transform from the second excited state to the first excited state and the first excited state to the ground state at very high probability,the system produces laser.

Jiguang zazhi•Jan 1, 2006•0 citations

The coherence properties of radiation and one-step absorption in four-level atom

Feng Gao

The radiation and one-step absorption of the four-level atom is studied.Atom's motivated state is not stable,it inevitably disintegrate into the lower energy state,which makes the phenomenon of radiation.This paper is on the basis of theories of quantum mechanics and Kraus operator,utilizing the reducible density rectangular method to probe into the transformation of density matrix opposite angles element and non-opposite angles element of the four-level atom,which in the case of the radiation and one-step absorption.The coherence properties of quantum states are analyzed.

•Jan 1, 2007•0 citations

Excited-state nonlinear absorption and its description using density matrix theory

Ruibo Wang

A density matrix theory with a ten-energy-level model in the molecular system irradiated bya pulsed laser at non-resonant wavelength is proposed. The reverse saturable absorption under ns and pspulses and the transformation from reverse saturable absorption to saturable absorption under strong ps pulses are described by this model. The correctness of the theoretical model is proved by experiments.

Science China Mathematics•Jan 1, 1995•0 citations

Time development of a driven three-level lambda system: A case study

James P. Lavine

How does a driven system with many energy levels approach its steady state? Insights are gained by studying a system with three energy levels when the ground state is excited by a laser. The time-dependent occupation probabilities of the three energy levels show students how the system develops in time. The occupation probabilities come from the numerical solution of the Liouville-von Neumann equations for the density operator matrix elements when relaxation is included. A combination of the Interaction Picture, the Rotating Wave Approximation, and the assumption of resonance permit the eigenvalues of the Liouville-von Neumann equations to be found numerically and in closed-form in certain limits. The two methods are complementary and help students understand time-dependent systems. In addition, the eigenvalues allow the short-time and the long-time occupation probabilities to be connected to the relaxation parameters and the magnitude of the laser's electric field. Thus, this model three-level system illuminates how a driven system behaves over time and provides guidance for students studying time-dependent systems.

arXiv:2004.01948•Apr 4, 2020•0 citations

Coherence effect of high excited state atoms

Zhao Jian-Dong, Xin Jie

The ladder three-level system including ground state, excited state and high excited state is investigated by using the density matrix equations. The coherence effect of ladder three-level system is analyzed, and absorption and dispersion curves of weak probe laser are obtained. The effects of interaction between high excited atoms and external electric field on the coherence effect are also investigated. The result shows that the interaction between high excited atoms or the external field can make the absorption curve and the dispersion curve shifted.

Acta Physica Sinica•Jan 1, 2012•0 citations

Decoherence of Relative Phase Damping in the Three-level Atom

Gao Feng

The transformation from quantum pure state to mixed state is discussed.On the basis of density matrix and Kraus theory,the decoherence of relative phase damping in three-level atom is studied.The calculation has shown the density operator to the decoherence of relative phase damping in three-level atom.It comes to a conclusion that the decoherence of relative phase damping is due to the decay to the non-diagonal element of density matrix.

Journal of Hengyang Normal University•Jan 1, 2007•0 citations
Ruby laser is a three-level system.This paper utilizes theories of Kraus operator,to analysis the three-level system which is in the case of absorption as well as radiation .The object of the research is to probe into the transformation properties of density matrix.The result show that when particles transform from ground state to the second excitated state and from the second excitated state to the first excitated state at very high probability,the system forms reversion of particles and prepares for producing laser.It also show that when particles transform from the first excitated state to the ground state at very high probability,the system produces laser.
Solid laser is a four-level system.This paper utilizes theories of quantum mechanics and Kraus operator,to analysis the four-level system which in the case of absorption as well as radiation.The object of the research is to probe into the transformation properties of density matrix.The result shows that probability of absorption and radiation condition is satisfied,between the second excited state and the first excited state forms reversion of particles and prepares for producing laser.It also shows that when particles transform from the second excited state to the first excited state and the first excited state to the ground state at very high probability,the system produces laser.
The radiation and one-step absorption of the four-level atom is studied.Atom's motivated state is not stable,it inevitably disintegrate into the lower energy state,which makes the phenomenon of radiation.This paper is on the basis of theories of quantum mechanics and Kraus operator,utilizing the reducible density rectangular method to probe into the transformation of density matrix opposite angles element and non-opposite angles element of the four-level atom,which in the case of the radiation and one-step absorption.The coherence properties of quantum states are analyzed.
How does a driven system with many energy levels approach its steady state? Insights are gained by studying a system with three energy levels when the ground state is excited by a laser. The time-dependent occupation probabilities of the three energy levels show students how the system develops in time. The occupation probabilities come from the numerical solution of the Liouville-von Neumann equations for the density operator matrix elements when relaxation is included. A combination of the Interaction Picture, the Rotating Wave Approximation, and the assumption of resonance permit the eigenvalues of the Liouville-von Neumann equations to be found numerically and in closed-form in certain limits. The two methods are complementary and help students understand time-dependent systems. In addition, the eigenvalues allow the short-time and the long-time occupation probabilities to be connected to the relaxation parameters and the magnitude of the laser's electric field. Thus, this model three-level system illuminates how a driven system behaves over time and provides guidance for students studying time-dependent systems.
The ladder three-level system including ground state, excited state and high excited state is investigated by using the density matrix equations. The coherence effect of ladder three-level system is analyzed, and absorption and dispersion curves of weak probe laser are obtained. The effects of interaction between high excited atoms and external electric field on the coherence effect are also investigated. The result shows that the interaction between high excited atoms or the external field can make the absorption curve and the dispersion curve shifted.