The ability to control the charge state of individual molecules wired in two-terminal single-molecule junctions is a key challenge in molecular electronics, particularly in relation to the development of molecular memory and other computational componentry. Here we demonstrate that single porphyrin molecular junctions can be reversibly charged and discharged at elevated biases under ambient conditions due to the presence of a localised molecular eigenstate close to the Fermi edge of the electrodes. In particular, we can observe long-lived charge-states with lifetimes upwards of 1–10 seconds after returning to low bias and large changes in conductance, in excess of 100-fold at low bias. Our theoretical analysis finds charge-state lifetimes within the same time range as the experiments. The ambient operation demonstrates that special conditions such as low temperatures or ultra-high vacuum are not essential to observe hysteresis and stable charged molecular junctions.

中文翻译：

---

卟啉-胶带连接在环境条件下的长寿命带电状态

控制连接在两个末端单分子结中的单个分子的电荷状态的能力是分子电子学中的一项关键挑战，特别是与分子记忆和其他计算组件的发展有关。在这里，我们证明，由于存在接近电极费米边缘的局部分子本征态，在环境条件下，单个卟啉分子结可以在升高的偏压下可逆地充电和放电。特别是，我们可以观察到长寿命的电荷状态，恢复到低偏压后的寿命可达1-10秒，电导的变化很大，在低偏压下超过100倍。我们的理论分析发现与实验相同时间范围内的电荷状态寿命。