Difference between revisions of "Eigenfields.m"

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==Arguments==
 
==Arguments==
  
−
    Iz - isotropic part of the laboratory frame Hamiltonian  
+
 
−
            operator (Hilbert space) or commutation superopera-
+
Hz - field-dependent part of the laboratory-frame Hamiltonian operator
−
            tor (Liouville space, containing only Zeeman terms
+
      in Hilbert space, or commutation superoperator in Liouville space,
−
            at 1 Tesla
+
      normalised to 1 Tesla
−
+
 
−
    Qz - anisotropic part of the laboratory frame Hamiltoni-
+
Hc - field-independent part of the laboratory-frame Hamiltonian operator
−
            an operator (Hilbert space) or commutation supero-
+
      in Hilbert space, or commutation superoperator in Liouville space,
−
            perator (Liouville space, containing only Zeeman
+
      containing couplings and offsets
−
            terms at 1 Tesla
+
 
−
+
Hmw - observable operator in Hilbert space, or observable vector in
−
    Ic  - isotropic part of the laboratory frame Hamiltonian
+
      Liouville space, without the amplitude prefactor
−
            operator (Hilbert space) or commutation superopera-
+
 
−
            tor (Liouville space, containing all spin-spin cou-
+
parameters.window     - magnetic-field window, Tesla
−
            plings, but no Zeeman terms
+
 
−
+
parameters.mw_freq     - microwave frequency, Hz
−
    Qc  -  anisotropic part of the laboratory frame Hamiltoni-
+
 
−
            an operator (Hilbert space) or commutation supero-
+
parameters.orientation - three Euler angles in radians specifying the
−
            perator (Liouville space, containing all spin-spin
+
                        system orientation
−
            couplings, but no Zeeman terms
+
 
−
+
parameters.tm_tol     - relative transition moment tolerance
−
    Hmw - observable operator (Hilbert space) or observable
+
 
−
            vector (Liouville space), without the amplitude  
+
parameters.pp_tol     - peak position tolerance in Tesla; this should
−
            prefactor
+
                        be much smaller than the typical line width
−
+
 
−
    parameters.window   - magnet field window, Tesla
+
parameters.fwhm        - transition full width at half maximum, 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==
 
==Outputs==
  
−
    tf     - vector of transition fields in Tesla
+
 
−
+
tran.tf - vector of transition fields in Tesla
−
    tm     - vector of transition moments
+
 
−
+
tran.tm - vector of transition moments
−
    tw     - vector of transition FWHMs in Tesla
+
 
 +
tran.tw - vector of transition FWHMs in Tesla
 +
 
 +
tran.pd - vector of energy level population differences
 +
 
 +
tran.ti - transition identity array, one row per transition
 +
 
 +
tran.tj - vector of scaled field-sweep Jacobians
  
 
==Notes==
 
==Notes==

Revision as of 15:22, 5 June 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

    tran=eigenfields(spin_system,parameters,Hz,Hc,Hmw)

Arguments

Hz - field-dependent part of the laboratory-frame Hamiltonian operator

     in Hilbert space, or commutation superoperator in Liouville space,
     normalised to 1 Tesla

Hc - field-independent part of the laboratory-frame Hamiltonian operator

     in Hilbert space, or commutation superoperator in Liouville space,
     containing couplings and offsets

Hmw - observable operator in Hilbert space, or observable vector in

     Liouville space, without the amplitude prefactor

parameters.window - magnetic-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.fwhm - transition full width at half maximum, Tesla

Outputs

tran.tf - vector of transition fields in Tesla

tran.tm - vector of transition moments

tran.tw - vector of transition FWHMs in Tesla

tran.pd - vector of energy level population differences

tran.ti - transition identity array, one row per transition

tran.tj - vector of scaled field-sweep Jacobians

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