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FQHETorusBosonsWithSpinAndTranslations provides exact diagonalization for bosons with a spin 1/2 degree of freedom on a torus geometry and any generic two body interaction. It fully supports magnetic translations in both directions. It is the spinful counterpart of FQHETorusBosonsWithTranslations (see this code for additional details).

For SU(2)-symmetric interaction, the pseudopotential file is similar to FQHETorusBosonsWithTranslations. As an example, let's consider the Halperin (221) state. The exact interaction can be enconded with the following file

   Name = halperin_221
   Pseudopotentials = 1.0

Then the command

$PATHTODIAGHAM/build/FQHE/src/Programs/FQHEOnTorus/FQHETorusBosonsWithSpinAndTranslations -p 4 -l 6 --use-lapack --interaction-file pseudopotentials_221.dat

produces a file bosons_torus_su2_halperin_221_n_4_2s_6_sz_0_ratio_1.000000.dat. Its content should look like

   # Kx Ky E
   0 0 -1.3322676295502e-15
   0 0 0.73294529995177
   0 0 0.83998531343515
   0 0 0.89853855304335
   0 0 0.9399234125861
   0 0 1.0150775727123

Kx is the relative momentum and Ky the centre of mass momentum. By default, only the Sz=0 sector is computed. Other sectors can be accessed using the -s option. This options takes twice Sz as an integer parameter.

For a generic (i.e.e non SU(2)-symmetric) interaction, the pseudopotentials can be set between per spin-component, i.e. up-up, down-down or up-down. For example the Halperin (220) state can be obtained with the following pseudopotential file

   Name = halperin_220
   PseudopotentialsUpUp = 1.0
   PseudopotentialsDownDown = 1.0
   PseudopotentialsUpDown = 0.0

Many options such as fixing the aspect ratio of the torus are identical to FQHEFermionsTorusWithTranslation. In particular, if you intend to use the Lanczos algorithm, we strongly advise to look at the explanations there.