Hamiltonian

This section covers the final stage of the AutoMPO pipeline: assembling an MPO from a populated interaction list, and the three built-in model builders.

Functions

Function	Description
build_hamiltonian	Assemble Hamiltonian MPO from interactions
build_heisenberg	Heisenberg spin model
build_free_fermion	Spinless free-fermion (tight-binding) model
build_hubbard	Hubbard model

Pipeline Position

(interactions, spc, L)    ← from build_interaction()
            │
            ▼ build_hamiltonian(interactions, L, spc)
            │
            └── MPO

build_hamiltonian accumulates each interaction as a rank-1 MPO update via Nicole's oplus, then compresses the result. The built-in model builders (build_heisenberg, etc.) are called internally by build_interaction, but can also be invoked directly for custom pipelines.

See Also

• Interaction — input to build_hamiltonian.
• MPO — output type.
• AutoMPO from TOML example