正常金属/半导体/d波超导体隧道结中的隧穿谱和散粒噪声

Transport Propertise and Shot Noise in Normal Metal-semiconductor-d-wave Superconductor Junction

利用Blonder-Tinkhanr-Klapwijk(BTK)理论求解了Bogoliubov-de Genner(BDG)方程,再结合Landauer-Büttiker公式,计算正常金属/半导体/d波超导体隧道结系统的隧穿系数,研究了隧穿谱和散粒噪声.在Rashba自旋轨道耦合参数一定的情况下,计算了散粒噪声和隧穿谱随偏压的变化.结果表明,电子入射角度θ和d波超导配对势都可以影响散粒噪声和隧穿谱.研究证明:d波超导体表面有零能束缚态存在;Andreev反射电导可以达到正常隧穿的2倍;散粒噪声被抑制的程度很大;半导体厚度L为3ε0的整数倍与半导体厚度L为非3ε0的整数倍时的散粒噪声和隧穿谱随偏压的变化有明显的区别.

Based on Landauer-Büttiker formula and the Bogoliubov-de Genner（BDG） equation which has been solved by the Blonder-Tinkhanr-Klapwijk （BTK） theory,the normal metal-semiconductor-d-wave superconductor＇s tunneling junction is calculated,tunneling spectrum and shot noise noise are studied.The result indicates that the electron-injection angle and d-wave superconductivity pair potential may affect the shot noise and the tunneling spectrum;a sizable areal density of midgap states exists on（110） surface of d-wave superconductor;the Andreev reflection electron conductance is two times as the normal tunneling conductance;the shot-noise spectroscopy is seriously influenced by the surface electronic states of the d-wave superconductor.When the thickness of Semiconductor is integral multiples of 3,the behaviors of tunneling spectrum are qualitatively different with that of shot noise when the thickness of semiconductor is not integral multiples of 3.