Chiesa A, Petiziol F, Chizzini M, Santini P, Carretta S
Università di Parma, Dipartimento di Scienze Matematiche, Fisiche e Informatiche, I-43124 Parma, Italy.
Gruppo Collegato di Parma, INFN-Sezione di Milano-Bicocca, 43124 Parma, Italy.
J Phys Chem Lett. 2022 Jul 21;13(28):6468-6474. doi: 10.1021/acs.jpclett.2c01602. Epub 2022 Jul 11.
We pinpoint the key ingredients ruling decoherence in multispin clusters, and we engineer the system Hamiltonian to design optimal molecules embedding quantum error correction. These are antiferromagnetically coupled systems with competing exchange interactions, characterized by many low-energy states in which decoherence is dramatically suppressed and does not increase with the system size. This feature allows us to derive optimized code words, enhancing the power of the quantum error correction code by orders of magnitude. We demonstrate this by a complete simulation of the system dynamics, including the effect of decoherence driven by a nuclear spin bath and the full sequence of pulses to implement error correction and logical gates between protected states.
我们确定了多自旋簇中支配退相干的关键成分，并设计系统哈密顿量以设计嵌入量子纠错的最优分子。这些是具有竞争交换相互作用的反铁磁耦合系统，其特征在于许多低能态，其中退相干被显著抑制且不随系统大小增加。这一特性使我们能够推导出优化的码字，将量子纠错码的能力提高几个数量级。我们通过对系统动力学的完整模拟来证明这一点，包括核自旋浴驱动的退相干效应以及在受保护状态之间实现纠错和逻辑门的完整脉冲序列。
