WAVEPACKET APPROACHES TO DISSIPATIVE QUANTUM DYNAMICS
type: CreativeWork
description: Many processes arising in Chemistry, Physics and Biology show quantum effects. Representative examples are chemical reactions involving light atoms, energy transfer in complex environments, electronic and geometrical properties of complex and bulk systems, tunneling phenomena etc. Theoretical Chemistry deals with such kind of problems with the help of numerical solutions of the Time Dependent Schrodinger Equation (TDSE). On the other hand, when classical effects are most relevant as, for example, in large dynamical systems like proteins at room temperature, Theoretical Chemistry deals with this problems with the help of numerical solution of the Newton's equations. Solving numerically the TDSE is much more expansive than solving the classical Newton's equations of motion. Thus, often mixed descriptions are used treating the system at the exact -quantum- level and the environment at the approximated classical level. When a full quantum approach is needed both for the system and for the environment (as, for example, in processes involving quantum objects, such as light atoms, energy transfer in small molecules interacting with a thermal bath at low temperature, and so on), one faces with so called Open Quantum Systems, and the corresponding dynamics is generally dissipative. In open quantum systems the wavefunction description fails because of a lack of the complete knowledge of the state. It is then necessary to switch to the density matrix description, which contains all the information. The system dynamics is affected by the presence of the bath depending on the interactions between them. If the coupling is small, than the system evolves in time without been affected by the environment. If the system is initially prepared as a pure state, then the dynamics is coherent. On the other hand if system and bath are strongly interacting, than the system dynamics is modified by the presence of the bath and described by a mixture of states. Under the condition of strong cou…
abstract: Many processes arising in Chemistry, Physics and Biology show quantum effects. Representative examples are chemical reactions involving light atoms, energy transfer in complex environments, electronic and geometrical properties of complex and bulk systems, tunneling phenomena etc. Theoretical Chemistry deals with such kind of problems with the help of numerical solutions of the Time Dependent Schrodinger Equation (TDSE). On the other hand, when classical effects are most relevant as, for example, in large dynamical systems like proteins at room temperature, Theoretical Chemistry deals with this problems with the help of numerical solution of the Newton's equations. Solving numerically the TDSE is much more expansive than solving the classical Newton's equations of motion. Thus, often mixed descriptions are used treating the system at the exact -quantum- level and the environment at the approximated classical level. When a full quantum approach is needed both for the system and for the environment (as, for example, in processes involving quantum objects, such as light atoms, energy transfer in small molecules interacting with a thermal bath at low temperature, and so on), one faces with so called Open Quantum Systems, and the corresponding dynamics is generally dissipative. In open quantum systems the wavefunction description fails because of a lack of the complete knowledge of the state. It is then necessary to switch to the density matrix description, which contains all the information. The system dynamics is affected by the presence of the bath depending on the interactions between them. If the coupling is small, than the system evolves in time without been affected by the environment. If the system is initially prepared as a pure state, then the dynamics is coherent. On the other hand if system and bath are strongly interacting, than the system dynamics is modified by the presence of the bath and described by a mixture of states. Under the condition of strong cou…
author: F. Martelli
language: eng
keywords: dissipative, quantum, dynamics, exciton, transfer, coherences, hydrodynamics, Settore CHIM/02 - Chimica Fisica
date published: 2010-12-14
date modified: 2026-07-27T20:19:17Z
provider: Università degli Studi di Milano
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Università degli Studi di Milano

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2434/150221