Topological fluctuating electron-hole Cooper pairs in graphene-GaAs heterostructures
نویسندگان
چکیده
Fluctuating Cooper pairs formed by spatially separated electrons and holes are precursors of their equilibrium condensation. Their presence strongly impacts transport phenomena interlayer tunneling in double-layer systems above the transition temperature. Here, we consider a hybrid graphene/quantum-well system focus on dynamics fluctuating conventional Dirac holes. We demonstrate that chiral nature is manifested two (almost) degenerate competing pairing channels, which intertwined effective pseudospin-orbit interactions. argue spectrum Ginzburg-Landau Hamiltonian describing energetics geometrically nontrivial can be characterized half-integer topological Chern number. derive kinetic equation for geometries generate anomalous velocities distinct geometrical origins. These intricately connected with Berry curvature quantum metric Hamiltonian, respectively. The resulting contributions to conductivity singular at temperature, discuss possible setups experimental observation.
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ژورنال
عنوان ژورنال: Physical review
سال: 2021
ISSN: ['0556-2813', '1538-4497', '1089-490X']
DOI: https://doi.org/10.1103/physrevb.104.245436