quri_parts.chem.ansatz.gate_fabric module#

class GateFabric(n_spin_orbitals, n_layers, include_pi=False)#

Bases: ImmutableLinearMappedUnboundParametricQuantumCircuit

Parametric quantum circuit that conserves the number of particles. Note that this circuit conserves the particle number only if the state applied to is represented based on the Jordan-Wigner transformation.

Ref.

[1] Anselmetti et al., Local, expressive, quantum-number-preserving VQE ansätze for fermionic systems, 2021 New J. Phys. 23 113010, DOI 10.1088/1367-2630/ac2cb3

See also PennyLane’s documentations, qml.GateFabric

Parameters:

  • n_spin_orbitals (int) – Number of spin orbitals.

  • n_layers (int) – Number of layers \(D\).

  • include_pi (bool) – If True, the optional constant \(\hat{\Pi}=\textrm{QNP}_{\textrm{OR}}(\pi)\) gate is inserted. This option does not seem to affect the expressiveness of the quantum circuit, but setting True can be advantageous during gradient-based parameter optimization [1].