论文标题
自动与互相关的噪声
Auto- versus cross-correlation noise
论文作者
论文摘要
在多探针导体的末端表达电流及其波动，就注入费米海的载体的波函数而言，提供了对电流物理物理学的新见解。这种方法有助于我们确定对射击噪声的物理上不同的贡献。在量子相干方向上，当电流通过非重叠的波包携带时，不同导线中电流波动的乘积，即互相关噪声，仅由波数据包的持续时间确定。相比之下，当电流波动在一个铅（自动相关噪声）中的平方是由波包的相干性确定的，这与波数据包在能量中的扩散有关。当自动相关噪声仅取决于连贯性时，这两个贡献可以分别解决。根据这些贡献，对射击噪声的分析尤其可以预测，没有具有真实波函数的单个行进粒子，例如Majorana fermions，可以在费米海中以干净的方式创建，也就是说，而没有伴随的电子孔对。
Expressing currents and their fluctuations at the terminals of a multi-probe conductor in terms of the wave functions of carriers injected into the Fermi sea provides new insight into the physics of electric currents. This approach helps us to identify two physically different contributions to shot noise. In the quantum coherent regime, when current is carried by non-overlapping wave-packets, the product of current fluctuations in different leads, the cross-correlation noise, is determined solely by the duration of the wave packet. In contrast, the square of the current fluctuations in one lead, the auto-correlation noise, is additionally determined by the coherence of the wave-packet, which is associated with the spread of the wave packet in energy. The two contributions can be addressed separately in the weak back-scattering regime, when the auto-correlation noise depends only on the coherence. Analysis of shot noise in terms of these contributions allows us, in particular, to predict that no individual travelling particles with a real wave function, such as Majorana fermions, can be created in the Fermi sea in a clean manner, that is, without accompanying electron-hole pairs.
