fastdla.generators.spin_chain.translation_eigenspace

fastdla.generators.spin_chain.translation_eigenspace(jphase, basis=None, num_spins=None, shift=1, npmod=np)

Extract an eigenspace of the translation.

Parameters:

• jphase (int) – Integer \(j\) of the \(T_s\) eigenvalue \(e^{2\pi i j s /N}\).

• basis (Optional[numpy.ndarray]) – The basis matrix \(B\).

• num_spins (Optional[int]) – Number of spins \(N\).

• shift (int) – Unit of translation \(s\).

Return type:

numpy.ndarray

Returns:

A matrix whose columns form the orthonormal basis of the eigen-subspace.