Rice-Mele Model

Purpose and structure

The Rice-Mele chain extends SSH with alternating hoppings and staggered onsite energies:

$$ t_{\rm intra}=t+\delta,\qquad t_{\rm inter}=t-\delta, $$

with onsite values $+\Delta$ on $A$ and $-\Delta$ on $B$.

SSH and Rice-Mele unit cells

Basis and use

The single-particle dimension is $2N_c$.

from quantum_lattice_models import rice_mele_model

H = rice_mele_model(
    n_cells=10, hopping=1.0, dimerization=0.25, staggering=0.5
)

Parameters

Builder Parameter Type Default Constraint
rice_mele_model n_cells int 8 >= 1
rice_mele_model hopping float 1.0
rice_mele_model dimerization float 0.25
rice_mele_model staggering float 0.5
rice_mele_model periodic bool False

User notes

Nonzero staggering breaks the SSH sublattice symmetry and generally shifts edge-state energies away from zero.