面向分子性质的资源高效型量子选择组态相互作用方法
Resource-efficient quantum-selected configuration interaction for molecular properties
中文总结 AI 辅助
该研究针对量子选择组态相互作用在有噪声量子设备上的电路复杂度问题，构建紧凑哈密顿量，在IIIA族一氟化物模拟中实现近二次标度提升，20量子比特TlF体系的电路深度与两量子比特门数缩减超98%，PDMs吻合度达99.99%，验证了方法的可扩展性。
中文摘要 AI 辅助
量子选择组态相互作用通过参考波函数的实时演化及在所得选择子空间中对角化哈密顿矩阵来识别重要的行列式基函数。然而，在有噪声的量子设备上实现全电子哈密顿量会导致电路复杂度迅速提升，限制了其可扩展性。为解决这一问题，我们识别出主导费米子激发算符，并开展参考态保真度损失分析以构建紧凑哈密顿量，在保持高精度的同时降低了计算开销。将该框架应用于IIIA族一氟化物（BF、AlF、GaF、InF及TlF），所提框架实现了哈密顿项标度的近二次提升，支持资源高效型模拟。我们利用该框架计算了上述体系的相对论基态能量与永久电偶极矩（PDMs），经模拟验证框架后，在IBM Marrakesh处理器上针对AlF和TlF开展了硬件执行，采用最多20量子比特的活性空间。对于20量子比特的TlF体系，简化后的哈密顿量在电路深度和两量子比特门数量上均实现了98%以上的缩减，量子硬件所得PDMs与完全活性空间组态相互作用值的吻合度达99.99%。这些结果证明了该方法在有噪声中等规模量子设备上的可扩展性。
英文摘要
The quantum-selected configuration interaction identifies important determinantal basis functions through real-time evolution of a reference wavefunction and diagonalizing the Hamiltonian matrix in the resulting selected subspace. However, implementing the full electronic Hamiltonian on noisy quantum devices leads to rapidly increasing circuit complexity, limiting its scalability. To address this issue, we identify the dominant fermionic excitation operators and perform reference-state fidelity loss analysis to construct a compact Hamiltonian, reducing computational overhead while retaining high precision. Applied to Group IIIA monofluorides (BF, AlF, GaF, InF, and TlF), the proposed framework achieves a near-quadratic improvement in Hamiltonian-term scaling, enabling resource-efficient simulations. We employ this framework to compute the relativistic ground-state energies and permanent electric dipole moments (PDMs) of the systems under consideration. After validating the framework via simulations, we demonstrate hardware execution for AlF and TlF on the IBM Marrakesh processor using active spaces of up to 20 qubits. For a 20-qubit TlF system, the reduced Hamiltonian yields a reduction of higher than $ 98\%$ in both circuit depth and two-qubit gate counts, with the resulting PDMs from quantum hardware matching complete active space configuration interaction values within $99.99\%$. These results demonstrate the scalability of this approach on noisy intermediate-scale quantum devices.
