mindquantum.simulator.mqchem.CIHamiltonian

class mindquantum.simulator.mqchem.CIHamiltonian(fermion_hamiltonian: FermionOperator)[source]

A wrapper for a fermionic Hamiltonian to be used with the MQChemSimulator.

This class stores a fermionic Hamiltonian for efficient expectation value calculations within a specific CI space.

Note

This Hamiltonian object is specifically designed for the MQChemSimulator and is not compatible with the standard state-vector Simulator.

Parameters: fermion_hamiltonian (FermionOperator) – A normal-ordered fermionic Hamiltonian.

Examples

>>> from mindquantum.core.operators import FermionOperator
>>> from mindquantum.simulator import mqchem
>>> ham_op = FermionOperator('0^ 0', 1.0) + FermionOperator('1^ 1', 0.5)
>>> ci_ham = mqchem.CIHamiltonian(ham_op)
>>> ci_ham
  1 [0^ 0] +
1/2 [1^ 1]

get_cpp_obj(backend, n_qubits, n_electrons)[source]

Return the underlying C++ CppCIHamiltonian object for a given backend.

Note

This method is for internal use by the MQChemSimulator.

Parameters

backend – The C++ backend module (_mq_chem.float or _mq_chem.double).
n_qubits (int) – The total number of qubits (spin-orbitals) in the system.
n_electrons (int) – The total number of electrons in the system.

Returns

The C++ object used for simulation.