qlinks.conventions package

Submodules

qlinks.conventions.qlm module

qlinks.conventions.qlm.staggered_charges_from_sites(lattice, *, magnitude=1, convention='even_positive')

Generate staggered background charges on lattice sites.

The charge is assigned by the parity of the unit-cell coordinate:

eta(r) = (-1) ** sum(cell coordinates)

For a square lattice, this is simply:

eta(x, y) = (-1) ** (x + y)

Parameters:

• lattice (LatticeGraph) – Lattice whose sites carry the Gauss-law charges.

• magnitude (int) – Absolute value of the staggered charge.

• convention (Literal['even_positive', 'odd_positive']) –

  “even_positive”:

  even sublattice gets +magnitude, odd sublattice gets -magnitude.

  ”odd_positive”:

  even sublattice gets -magnitude, odd sublattice gets +magnitude.

Returns:

Integer array of shape (lattice.num_sites,), ordered by site id.

Return type:

charges

qlinks.conventions.qlm.square_qdm_staggered_charges(lattice, *, magnitude=None, charge_normalization='spin_half', convention='even_positive')

Staggered charges for the square-lattice QDM-to-QLM mapping.

For the current spin-half flux convention E_l in {-1, +1}, the close-packed QDM constraint

one dimer touching each site

maps naturally to a staggered Gauss law with charge magnitude 1 on the square lattice.

Parameters:

• lattice (SquareLattice) – SquareLattice instance.

• charge_normalization (Literal['integer_flux', 'spin_half']) –

  “spin_half”:

  The user-facing charges are ±1, matching the spin-half flux convention.

  ”integer_flux”:

  The user-facing charges are ±2, matching the integer-flux convention where E_l in {-2, 0, +2}.

• convention (Literal['even_positive', 'odd_positive']) – Which sublattice receives the positive charge.

• magnitude (int | None)

Returns:

Integer array ordered by site id.

Return type:

charges

Module contents

qlinks.conventions.square_qdm_staggered_charges(lattice, *, magnitude=None, charge_normalization='spin_half', convention='even_positive')

Staggered charges for the square-lattice QDM-to-QLM mapping.

For the current spin-half flux convention E_l in {-1, +1}, the close-packed QDM constraint

one dimer touching each site

maps naturally to a staggered Gauss law with charge magnitude 1 on the square lattice.

Parameters:

• lattice (SquareLattice) – SquareLattice instance.

• charge_normalization (Literal['integer_flux', 'spin_half']) –

  “spin_half”:

  The user-facing charges are ±1, matching the spin-half flux convention.

  ”integer_flux”:

  The user-facing charges are ±2, matching the integer-flux convention where E_l in {-2, 0, +2}.

• convention (Literal['even_positive', 'odd_positive']) – Which sublattice receives the positive charge.

• magnitude (int | None)

Returns:

Integer array ordered by site id.

Return type:

charges

qlinks.conventions.staggered_charges_from_sites(lattice, *, magnitude=1, convention='even_positive')

Generate staggered background charges on lattice sites.

The charge is assigned by the parity of the unit-cell coordinate:

eta(r) = (-1) ** sum(cell coordinates)

For a square lattice, this is simply:

eta(x, y) = (-1) ** (x + y)

Parameters:

• lattice (LatticeGraph) – Lattice whose sites carry the Gauss-law charges.

• magnitude (int) – Absolute value of the staggered charge.

• convention (Literal['even_positive', 'odd_positive']) –

  “even_positive”:

  even sublattice gets +magnitude, odd sublattice gets -magnitude.

  ”odd_positive”:

  even sublattice gets -magnitude, odd sublattice gets +magnitude.

Returns:

Integer array of shape (lattice.num_sites,), ordered by site id.

Return type:

charges