Difference between revisions of "Eigenfields.m"

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==See also==
 
==See also==
 
[[fieldsweep.m]]
 
[[fieldsweep.m]]
−
 
  
 
''Version 2.6, authors: [[Ilya Kuprov]]''
 
''Version 2.6, authors: [[Ilya Kuprov]]''

Revision as of 12:24, 25 April 2026

Computes resonance fields. For a Hamiltonian Hc+b*Hz, returns all magnetic fields b for which the difference between two eigenvalues of Hc+b*Hz is equal to the frequency provided, and the transition moment across the specified operator Hmw is significant.

Syntax

    [tf,tm,tw]=eigenfields(spin_system,parameters,Iz,Qz,Ic,Qc,Hmw)

Arguments

    Iz  -  isotropic part of the laboratory frame Hamiltonian 
           operator (Hilbert space) or commutation superopera-
           tor (Liouville space, containing only Zeeman terms
           at 1 Tesla

    Qz  -  anisotropic part of the laboratory frame Hamiltoni-
           an operator (Hilbert space) or commutation supero-
           perator (Liouville space, containing only Zeeman 
           terms at 1 Tesla

    Ic  -  isotropic part of the laboratory frame Hamiltonian
           operator (Hilbert space) or commutation superopera-
           tor (Liouville space, containing all spin-spin cou-
           plings, but no Zeeman terms

    Qc  -  anisotropic part of the laboratory frame Hamiltoni-
           an operator (Hilbert space) or commutation supero-
           perator (Liouville space, containing all spin-spin
           couplings, but no Zeeman terms

    Hmw -  observable operator (Hilbert space) or observable
           vector (Liouville space), without the amplitude 
           prefactor

    parameters.window   -  magnet field window, Tesla

    parameters.mw_freq  -  microwave frequency, Hz

    parameters.orientation - three Euler angles in radians
                             specifying the system orientation

    parameters.tm_tol   -  relative transition moment 
                           tolerance

    parameters.pp_tol   -  peak position tolerance in Tesla,
                           this should be much smaller than
                           the typical line width

    parameters.rspt_order - perturbation theory order to use
                            to account for the off-diagonal
                            part of the Hamiltonian, Inf for
                            exact diagonalisation

Outputs

    tf     -  vector of transition fields in Tesla

    tm     -  vector of transition moments

    tw     -  vector of transition FWHMs in Tesla

Notes

In Hilbert space, the very efficient Schweiger-Stoll method is used. In Liouville space, the very general but rather slow generalised eigensolver supplied with Matlab is used.

See also

fieldsweep.m

Version 2.6, authors: Ilya Kuprov