论文标题
在拓扑约瑟夫森连接中观察分数约瑟夫效应的最佳条件
Optimal Conditions for Observing Fractional Josephson Effect in Topological Josephson Junctions
论文作者
论文摘要
拓扑约翰逊连接（JJS），其中包含Majorana绑定状态，预计将展示4 $π$ - 周期性的电流相关关系，从而在微波辐照下导致Shapiro Steps的两步。我们使用电容性和电容分流的连接模型对拓扑JJ进行了动力学特性进行了数值计算，并广泛研究了Shapiro Steps的渐进演化，这是连接参数以及微波功率和频率的函数。我们的计算结果表明，质量智能Shapiro步骤的抑制，即分数AC Josephson效应的证据，通过连接电容和ICRN产物的增加以及微波频率的下降，即使在4 $π$ - periodic的超急症中的相同部分也可以显着增强。我们的研究提供了观察分数约瑟夫效应的最佳条件。此外，我们的新模型可用于从拓扑JJS的实验数据中精确量化拓扑超流。
Topological Josephson junctions (JJs), which contain Majorana bound states, are expected to exhibit 4$π$-periodic current-phase relation, thereby resulting in doubled Shapiro steps under microwave irradiation. We performed numerical calculations of dynamical properties of topological JJs using a modified resistively and capacitively shunted junction model and extensively investigated the progressive evolution of Shapiro steps as a function of the junction parameters and microwave power and frequency. Our calculation results indicate that the suppression of odd-integer Shapiro steps, i.e., evidence of the fractional ac Josephson effect, is enhanced significantly by the increase in the junction capacitance and IcRn product as well as the decrease in the microwave frequency even for the same portion of the 4$π$-periodic supercurrent. Our study provides the optimal conditions for observing the fractional ac Josephson effect; furthermore, our new model can be used to precisely quantify the topological supercurrent from the experimental data of topological JJs.
