def test_displacement():
def get_e_occu(idx):
res = np.zeros(len(mol_list))
res[idx] = 1
return res
gs = Mps.gs(mol_list, max_entangled=False)
gs = Mpo.onsite(mol_list, r"a^\dagger", mol_idx_set={0}).apply(gs).compress()
assert np.allclose(gs.e_occupations, get_e_occu(0))
gs = Mpo.displacement(mol_list, 0, 2).apply(gs)
assert np.allclose(gs.e_occupations, get_e_occu(2))
gs = Mpo.displacement(mol_list, 2, 0).apply(gs)
assert np.allclose(gs.e_occupations ,get_e_occu(0))
def _construct_flux_operator(self):
# construct flux operator
logger.debug("constructing flux operator")
j_list = []
for i in range(len(self.mol_list) - 1):
j1 = Mpo.displacement(self.mol_list, i,
i + 1).scale(self.mol_list.j_matrix[i,
i + 1])
j1.compress_config.threshold = 1e-5
j2 = j1.conj_trans().scale(-1)
j_list.extend([j1, j2])
j_oper = compressed_sum(j_list, batchsize=10)
logger.debug(f"operator bond dim: {j_oper.bond_dims}")
return j_oper