论文标题
高温超导体/石墨烯连接中的Andreev反射和Klein隧道
Andreev Reflection and Klein Tunneling in High-Temperature Superconductor/Graphene Junctions
论文作者
论文摘要
量子材料中的散射过程作为电子传输中的共振出现，包括密闭模式，安德里克特州和Yu-Shiba-Rusinov态。但是，在大多数情况下，这些共振是由单个散射机制驱动的。在这里，我们显示了由于两个同时散射机制的组合，一种来自超导性，另一个来自石墨烯P-N连接。这些共振源于Andreev反射和klein隧道，这些隧道发生在边界上的两个不同的石墨烯区域的两个不同接口区域，由于BI $ _2 $ _2 $ sr $ _2 $ _2 $ _2 $ _1 $ _1 $ _1 $ _1 $ cu $ _2 $ _2 $ _2 $ _2 $ _ $ _ $ _ $ _ $ _ $ _ {8+δ+δ+δ} $ unive $ _2 $ sr $ _2 $ _2 $ _2 $ _2 $ _2 $ _2 $ _1 $ _1 $ _2 $ _2} $。从p $^+$ - p和p-n配置的门控持续共振。在偏置能与诱导的超导间隙相当的偏置能量上方的振荡幅度的抑制表明，Andreev反射的贡献。我们的实验测量由此类界面中的量子传输计算支持，从而导致类似的共振。我们的结果提出了石墨烯/高温超导体异质结中的混合散射机制，对基于石墨烯的Josephson连接的潜在影响。
Scattering processes in quantum materials emerge as resonances in electronic transport, including confined modes, Andreev states, and Yu-Shiba-Rusinov states. However, in most instances, these resonances are driven by a single scattering mechanism. Here we show the appearance of resonances due to the combination of two simultaneous scattering mechanisms, one from superconductivity and the other from graphene p-n junctions. These resonances stem from Andreev reflection and Klein tunneling that occur at two different interfaces of a hole-doped region of graphene formed at the boundary with superconducting graphene due to proximity effects from Bi$_2$Sr$_2$Ca$_1$Cu$_2$O$_{8+δ}$. The resonances persist with gating the from p$^+$-p and p-n configurations. The suppression of the oscillation amplitude above the bias energy comparable to the induced superconducting gap indicates the contribution from Andreev reflection. Our experimental measurements are supported by quantum transport calculations in such interfaces, leading to analogous resonances. Our results put forward a hybrid scattering mechanism in graphene/high-temperature superconductor heterojunctions of potential impact for graphene-based Josephson junctions.
