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OpenMCTDHB v2.3
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OpenMCTDHB v2.3
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Go to the source code of this file.
Functions/Subroutines | |
| program | OpenMCTDHB |
| This is the main program. | |
| program OpenMCTDHB | ( | ) |
This is the main program.
Purpose: ! Solve the many-body Schrödinger equation for N identical bosons
i d/dt |Psi> = H |Psi>
using the MCTDHB algorithm. For a thorough description of the algorithm see the documentation and the publications.
In short, the MCTDHB algorithm provides the variationally optimal solution of the time-dependent many-boson Schrödinger equation, given an ansatz wave function in which N bosons are allowed to reside in M orbitals. The most striking feature of the MCTDHB algorithm is that the orbitals in which the many-body wave function is expanded are allowed to depend on time, and are determined by the principle of least action. By increasing the number of orbitals, the ansatz for the many-body wave function becomes more and more general and, therefore, the solution more accurate.
If only M=1 orbital is used to expand the many-body wave function, the MCTDHB equations reduce to the Gross-Pitaevskii equation. MCTDHB can threfore be considered the variational many-body generalization of the Gross-Pitaevkii mean-field. The current OpenMCTDHB code supports only up to M=2 orbitals. This allows to check whether Gross-Pitaevskii is OK to use for a given problem.
If the results converge (in regards to increasing the number of orbitals M) MCTDHB provides the numerically exact solution of the full time-dependent many-boson Schrödinger equation. To check this it is generally necessary to use more than M=2 orbitals. However, the current version of OpenMCTDHB only supports up to M=2 orbitals. More orbitals are on the road map for OpenMCTDHB .
Stationary states can be obtained by propagation in imaginary time.
Definition at line 121 of file OpenMCTDHB.F90.
1.7.3
