Molecular Nanomagnets may enable the implementation of qudit-based quantum error-correction codes which exploit the many spin levels naturally embedded in a single molecule, a promising step towards scalable quantum processors. To fully realize the potential of this approach, a microscopic understanding of the errors corrupting the quantum information encoded in a molecular qudit is essential, together with the development of tailor-made quantum error correction strategies. We address these central points by first studying dephasing effects on the molecular spin qudit produced by the interaction with surrounding nuclear spins, which are the dominant source of errors at low temperatures. Numerical quantum error correction codes are then constructed, by means of a systematic optimization procedure based on simulations of the coupled system-bath dynamics, that provide a striking enhancement of the coherence time of the molecular computational unit. The sequence of pulses needed for the experimental implementation of the codes is finally proposed.

分子纳米磁体可以实现基于 qudit 的量子纠错码，该码利用天然嵌入在单个分子中的许多自旋能级，这是朝着可扩展量子处理器迈出的有希望的一步。为了充分发挥这种方法的潜力，对破坏分子量子编码的量子信息的错误进行微观理解是必不可少的，同时还需要开发量身定制的量子纠错策略。我们通过首先研究与周围核自旋相互作用产生的分子自旋量子的移相效应来解决这些中心点，这是低温下误差的主要来源。然后构造数值量子纠错码，通过基于耦合系统浴动力学模拟的系统优化程序，显着提高了分子计算单元的相干时间。最后提出了代码的实验实现所需的脉冲序列。