Singlet and triplet Cooper pair splitting in superconducting-semiconducting hybrid nanowires

Kavli Affiliate: Michael Wimmer

| First 5 Authors: Guanzhong Wang, Tom Dvir, Grzegorz P. Mazur, Chun-Xiao Liu, Nick van Loo

| Summary:

In most naturally occurring superconductors, electrons with opposite spins
are paired up to form Cooper pairs. This includes both conventional $s$-wave
superconductors such as aluminum as well as high-$T_c$, $d$-wave
superconductors. Materials with intrinsic $p$-wave superconductivity, hosting
Cooper pairs made of equal-spin electrons, have not been conclusively
identified, nor synthesized, despite promising progress. Instead, engineered
platforms where $s$-wave superconductors are brought into contact with magnetic
materials have shown convincing signatures of equal-spin pairing. Here, we
directly measure equal-spin pairing, proximity-induced from an $s$-wave
superconductor into a semiconducting nanowire with strong spin-orbit
interaction. We demonstrate such pairing using spin-selective quantum dots by
showing that breaking a Cooper pair can result in two electrons with equal spin
polarization. Our results demonstrate controllable detection of singlet and
triplet pairing in the proximitized nanowire. Achieving such triplet pairing in
a sequence of quantum dots will be required for realizing an artificial Kitaev
chain.

| Search Query: ArXiv Query: search_query=au:”Michael Wimmer”&id_list=&start=0&max_results=10

Read More