Difference between revisions of "Relaxation.m"

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{{DISPLAYTITLE:relaxation.m}}
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{{DISPLAYTITLE:relaxation.m}} __NOTOC__
 
Relaxation superoperator.
 
Relaxation superoperator.
  
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     R=relaxation(spin_system,euler_angles)
 
     R=relaxation(spin_system,euler_angles)
  
==Arguments==
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==Parameters==
  
     euler_angles  - (optional) spin system orientation, for
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                     solid state systems at low temperature,
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                     where the thermal equilibrium depends
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     euler_angles  - three Euler angles, ZYZ active convention in radians,
                     on the orientation
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                    specifying system orientation relative to the input
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                     orientation; required by relaxation theories that
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                     support relaxation-rate anisotropy, and ignored by
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                     theories that do not
  
 
==Outputs==
 
==Outputs==
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# Spinach [[kernel_contexts|context functions]] include kinetics superoperators into the total Liovillian automatically.
 
# Spinach [[kernel_contexts|context functions]] include kinetics superoperators into the total Liovillian automatically.
 
# The function has been written for minimal memory footprint and performs aggressive memory recycling. Relaxation superoperator dimensions in excess of 1,000,000 are in practice feasible.
 
# The function has been written for minimal memory footprint and performs aggressive memory recycling. Relaxation superoperator dimensions in excess of 1,000,000 are in practice feasible.
 +
# Dissipative bosonic modes declared in inter.modes receive thermalised GKSL dissipators from [[rlx_modes.m]] in Liouville space formalisms; the euler_angles parameter refers to the spin subsystem only and has no effect on the mode terms.
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# Bosonic mode dissipation cannot be represented in Hilbert space: a warning is printed and the mode dissipators are omitted, while the rest of the superoperator is returned as usual.
  
 
==See also==
 
==See also==
[[equilibrium.m]], [[thermalize.m]], [[hamiltonian.m]], [[lindbladian.m]], [[kinetics.m]], [[magpump.m]]
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[[equilibrium.m]], [[thermalize.m]], [[hamiltonian.m]], [[lindbladian.m]], [[kinetics.m]], [[magpump.m]], [[bos2ist.m]], [[boson_mono.m]], [[boson_ortho.m]], [[centrans.m]], [[ct2ist.m]], [[enlev2bm.m]], [[enlev2ist.m]], [[oper2bm.m]], [[oper2ist.m]], [[operator.m]], [[orientation.m]], [[propagator.m]], [[sin_tran.m]], [[weyl.m]], [[rlx_modes.m]], [[device.m]], [[Kernel_functions]]
 
 
  
 
''Version 2.2, authors: [[Ilya Kuprov]], [[Luke Edwards]], [[Alexander Karabanov]], [[Walter Kockenberger]]''
 
''Version 2.2, authors: [[Ilya Kuprov]], [[Luke Edwards]], [[Alexander Karabanov]], [[Walter Kockenberger]]''

Latest revision as of 05:40, 6 August 2026

Relaxation superoperator.

Syntax

    R=relaxation(spin_system,euler_angles)

Parameters

    euler_angles  - three Euler angles, ZYZ active convention in radians,
                    specifying system orientation relative to the input
                    orientation; required by relaxation theories that
                    support relaxation-rate anisotropy, and ignored by
                    theories that do not

Outputs

    R             - relaxation superoperator

Notes

  1. A variety of relaxation theories are supported, see the relaxation theory parameters section of the online manual.
  2. Spinach context functions include kinetics superoperators into the total Liovillian automatically.
  3. The function has been written for minimal memory footprint and performs aggressive memory recycling. Relaxation superoperator dimensions in excess of 1,000,000 are in practice feasible.
  4. Dissipative bosonic modes declared in inter.modes receive thermalised GKSL dissipators from rlx_modes.m in Liouville space formalisms; the euler_angles parameter refers to the spin subsystem only and has no effect on the mode terms.
  5. Bosonic mode dissipation cannot be represented in Hilbert space: a warning is printed and the mode dissipators are omitted, while the rest of the superoperator is returned as usual.

See also

equilibrium.m, thermalize.m, hamiltonian.m, lindbladian.m, kinetics.m, magpump.m, bos2ist.m, boson_mono.m, boson_ortho.m, centrans.m, ct2ist.m, enlev2bm.m, enlev2ist.m, oper2bm.m, oper2ist.m, operator.m, orientation.m, propagator.m, sin_tran.m, weyl.m, rlx_modes.m, device.m, Kernel_functions

Version 2.2, authors: Ilya Kuprov, Luke Edwards, Alexander Karabanov, Walter Kockenberger