TY - JOUR
T1 - Statistical detection of Josephson, Andreev, and single quasiparticle currents in scanning tunneling microscopy
AU - Ko, Wonhee
AU - Dumitrescu, Eugene F.
AU - Maksymovych, Petro
N1 - Publisher Copyright:
© 2021 authors
PY - 2021/9
Y1 - 2021/9
N2 - We present a method to identify distinct tunneling modes in a tunable superconducting tunnel junction composed of a superconducting tip and a sample in a scanning tunneling microscope. Combining the relative decay constant of tunneling current extracted from I-V-z spectroscopy with its statistical analysis over the atomic disorders in the sample surface, we identified the crossover of dominant tunneling modes between single charge tunneling, Andreev reflection (AR), and Josephson tunneling with respect to the bias voltage at a measurement temperature nearly half of the critical temperature. The method enables one to determine the specific tunneling regime independently of the spectral shapes and to reveal intrinsic modulation of AR and Josephson current by disorder that will be crucial for superconducting quantum information processing.
AB - We present a method to identify distinct tunneling modes in a tunable superconducting tunnel junction composed of a superconducting tip and a sample in a scanning tunneling microscope. Combining the relative decay constant of tunneling current extracted from I-V-z spectroscopy with its statistical analysis over the atomic disorders in the sample surface, we identified the crossover of dominant tunneling modes between single charge tunneling, Andreev reflection (AR), and Josephson tunneling with respect to the bias voltage at a measurement temperature nearly half of the critical temperature. The method enables one to determine the specific tunneling regime independently of the spectral shapes and to reveal intrinsic modulation of AR and Josephson current by disorder that will be crucial for superconducting quantum information processing.
UR - http://www.scopus.com/inward/record.url?scp=85115889935&partnerID=8YFLogxK
U2 - 10.1103/PhysRevResearch.3.033248
DO - 10.1103/PhysRevResearch.3.033248
M3 - Article
AN - SCOPUS:85115889935
SN - 2643-1564
VL - 3
JO - Physical Review Research
JF - Physical Review Research
IS - 3
M1 - 033248
ER -