scholarly journals A TIME-DEPENDENT MULTI-DETERMINANT APPROACH TO NUCLEAR DYNAMICS

2013 ◽  
Vol 22 (06) ◽  
pp. 1350040 ◽  
Author(s):  
G. PUDDU
Keyword(s):  
Wave Function ◽  
Time Evolution ◽  
Krylov Subspace ◽  
Equations Of Motion ◽  
Strength Function ◽  
Time Dependent ◽  
Nuclear Wave Function ◽  
Nuclear Dynamics ◽  
Hartree Fock

We propose a Time-Dependent Multi-Determinant (TDMD) approach to the description of the time evolution of the nuclear wave functions. We use the Dirac variational principle to derive the equations of motion using as ansatz for the nuclear wave function a linear combination of Slater determinants. We prove explicitly that the norm and the energy of the wave function are conserved during the time evolution. This approach is a generalization of the time-dependent Hartree–Fock method to many Slater determinants. We apply this approach to a case study of 6 Li using the N3LO interaction renormalized to four major harmonic oscillator shells. We solve the TDMD equations of motion using Krylov subspace methods of Lanczos type. As an application, we discuss the isoscalar monopole strength function.

scholarly journals Angular distribution of scission neutrons studied with time-dependent Schrödinger equation

2018 ◽  
Vol 169 ◽  
pp. 00029
Author(s):  
Takahiro Wada ◽  
Tomomasa Asano ◽  
Nicolae Carjan
Keyword(s):  
Wave Function ◽  
Angular Distribution ◽  
Schrödinger Equation ◽  
Time Evolution ◽  
Schrodinger Equation ◽  
Initial Distribution ◽  
Time Dependent ◽  
Heavy Fragment ◽  
Fission Fragments ◽  
Asymmetric Fission

We investigate the angular distribution of scission neutrons taking account of the effects of fission fragments. The time evolution of the wave function of the scission neutron is obtained by integrating the time-dependent Schrodinger equation numerically. The effects of the fission fragments are taken into account by means of the optical potentials. The angular distribution is strongly modified by the presence of the fragments. In the case of asymmetric fission, it is found that the heavy fragment has stronger effects. Dependence on the initial distribution and on the properties of fission fragments is discussed. We also discuss on the treatment of the boundary to avoid artificial reflections

Squeezing caused by a change of mass in a harmonic oscillator

1989 ◽  
Vol 67 (2-3) ◽  
pp. 152-154 ◽  
Author(s):  
Fan Hong-Yi ◽  
H. R. Zaidi
Keyword(s):  
Harmonic Oscillator ◽  
Time Evolution ◽  
Equations Of Motion ◽  
Time Dependent ◽  
Mass Change ◽  
Transformation Time

It is shown that a mass change in a harmonic oscillator generates a squeezing transformation. Time-independent as well as time-dependent transformations are investigated. An expression for the interaction Hamiltonian responsible for squeezing and the equations of motion for the time evolution are derived.

scholarly journals Charge and Energy Transport through Quantum Dots

2015 ◽  
Author(s):  
Christian Schiegg ◽  
Michael Dzierzawa ◽  
Ulrich Eckern
Keyword(s):  
Quantum Dots ◽  
Density Matrix ◽  
Time Evolution ◽  
Stationary State ◽  
Energy Transport ◽  
Time Dependent ◽  
Hartree Fock ◽  
Wide Range ◽  
Quasi Stationary State ◽  
Energy Currents

We consider a model of interacting spinless fermions coupled to non-interacting leads. Initially a non-equilibrium situation is imposed by applying a bias voltage and temper- ature gradient across the system. The time-evolution of the density matrix leads to a quasi-stationary state from which charge and energy currents can be extracted. Numeri- cal results based on the time-dependent Hartree-Fock approximation are compared with exact currents obtained from discrete Hubbard-Stratonovich decoupling of the interac- tion for small systems. For a wide range of parameters the time-evolution of the currents is reasonably well described within the Hartree-Fock approach.

scholarly journals Recent progress of the sign problem in the Onishi formula

2018 ◽  
Vol 178 ◽  
pp. 02004
Author(s):  
Noritaka Shimizu ◽  
Takahiro Mizusaki ◽  
Makito Oi
Keyword(s):  
Wave Function ◽  
Recent Progress ◽  
Polynomial Function ◽  
Wave Functions ◽  
Nuclear Wave Function ◽  
Hartree Fock ◽  
Sign Problem

The Hartree-Fock-Bogoliubov (HFB) method is one of the major methods to study a nuclear wave function. We discuss the sign problem in the Onishi formula, which emerges in calculating the overlap between two HFB wave functions. The origin of this problem is elucidated by expanding the overlap as a polynomial function. This article is based on Ref.[1].

Sign in / Sign up

Export Citation Format

Share Document