Molecular Optimization for Nuclear Spin State Control via a Single Electron Spin Qubit by Optimal Microwave Pulses: Quantum Control of Molecular Spin Qubits

Quantum state control is one of the most important concepts in advanced quantum technology, emerging cybernetics and related fields. Molecular open shell entities can be a testing ground for implementing technology enabling us to manipulate molecular spin bits (molecular qubits). In well-designed spins consisting unpaired electron nuclear spins, electrons bus client qubits, respectively. Full which interact via hyperfine coupling, key issue computers (QCs). solid-state QCs, there are two approaches namely, direct by radio-wave (RF) pulses indirect interactions microwave applied qubits. Although latter less popular literature, indirectness has advantage greatly reducing unnecessary between qubit system its environment. this work, we investigate optimization find optimal experimental conditions afford achieve high fidelity gates scheme. present systems, directly controlled pulsed ESR techniques without manipulating individual resonance, but states indirectly steered interactions. Single crystals potassium hydrogen maleate (KHM) radical 13C-labeled malonyl chosen as typical qubits exemplify importance symmetry tensors their collinear properties. We have found that both non-collinearity principal axes coupling non-distinguishability/non-equivalency issues extremely reduce gate fidelity.