Efficient Preparation of Resource States for Hamiltonian Simulation and Universal Quantum Computation

Abstract: The direct compilation of algorithm-specific graph states in measurement-based quantum computation (MBQC) can lead to resource reductions in terms of circuit depth, entangling gates, and even the number of physical qubits. In this work, we extend previous studies on algorithm-tailored graph states to periodic sequences of generalized Pauli rotations, which commonly appear in, e.g., Trotterized Hamiltonian simulation. We first implement an enhanced simulated-annealing-based algorithm to find optimal periodic graph states within local-Clifford (LC-)MBQC. In addition, we derive a novel scheme for the preparation of resource states based on a graph state and a ladder of CNOT gates, which we term anticommutation-based (AC-)MBQC, since it uncovers a direct relationship between the graph state and the anticommutation matrix for the set of Hamilonians generating the computation. We also deploy our two approaches to derive universal resource states from minimal universal sets of generating Hamiltonians, thus providing a straightforward algorithm for finding the former. Finally, we demonstrate and compare both of our methods based on various examples from condensed matter physics and universal quantum computation.