Search results for "superfluid density"

showing 3 items of 3 documents

Supercurrent Induced Charge-Spin Conversion in Spin-Split Superconductors

2017

We study spin-polarized quasiparticle transport in a mesoscopic superconductor with a spin- splitting field in the presence of co-flowing supercurrent. In such a system, the nonequilibrium state is characterized by charge, spin, energy and spin energy modes. Here we show that in the presence of both spin splitting and supercurrent, all these modes are mutually coupled. As a result, the supercurrent can convert charge imbalance, that in the presence of spin splitting decays on a relatively short scale, to a long-range spin accumulation decaying only via inelastic scattering. This effect enables coherent charge-spin conversion controllable by a magnetic flux, and it can be detected by studyin…

Field (physics)superfluid densityFOS: Physical sciences02 engineering and technologyInelastic scattering01 natural sciencessuprajohteetSuperconductivity (cond-mat.supr-con)transport propertiesCondensed Matter::Superconductivity0103 physical sciences010306 general physicsSpin-½PhysicsSuperconductivityspin accumulationMesoscopic physicsspin currentta114Condensed matter physicsCondensed Matter - SuperconductivityCharge (physics)021001 nanoscience & nanotechnologyspin relaxationMagnetic fluxQuasiparticleCondensed Matter::Strongly Correlated Electrons0210 nano-technology
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Superfluid weight and Berezinskii-Kosterlitz-Thouless transition temperature of twisted bilayer graphene

2019

We study superconductivity of twisted bilayer graphene with local and non-local attractive interactions. We obtain the superfluid weight and Berezinskii-Kosterlitz-Thouless (BKT) transition temperature for microscopic tight-binding and low-energy continuum models. We predict qualitative differences between local and non-local interaction schemes which could be distinguished experimentally. In the flat band limit where the pair potential exceeds the band width we show that the superfluid weight and BKT temperature are determined by multiband processes and quantum geometry of the band.

suprajohtavuusINSULATORsuperfluid densitymultiband superconductivityFOS: Physical sciences02 engineering and technologyBKT transition01 natural sciences114 Physical sciencessuperconducting phase transitionSuperconductivity (cond-mat.supr-con)SuperfluidityMAGIC-ANGLEsuperconducting fluctuationsnanorakenteetCondensed Matter::SuperconductivityMesoscale and Nanoscale Physics (cond-mat.mes-hall)0103 physical sciencesgrafeeni010306 general physicsQuantumPhysicsSuperconductivityCondensed Matter::Quantum GasesCondensed matter physicsCondensed Matter - Mesoscale and Nanoscale PhysicsCondensed Matter::OtherSUPERCONDUCTIVITYCondensed Matter - SuperconductivityORDER021001 nanoscience & nanotechnologySTATEsuperconducting RFKosterlitz–Thouless transitionPairingDENSITYBerry connection and curvature0210 nano-technologyBilayer graphene
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Supercurrent-induced charge-spin conversion in spin-split superconductors

2018

We study spin-polarized quasiparticle transport in a mesoscopic superconductor with a spin-splitting field in the presence of coflowing supercurrent. In such a system, the nonequilibrium state is characterized by charge, spin, energy, and spin-energy modes. Here we show that in the presence of both spin splitting and supercurrent, all these modes are mutually coupled. As a result, the supercurrent can convert charge imbalance, which in the presence of spin splitting decays on a relatively short scale, to a long-range spin accumulation decaying only via inelastic scattering. This effect enables coherent charge-spin conversion controllable by a magnetic flux, and it can be detected by studyin…

spin accumulationspin currenttransport propertiessuperfluid densityCondensed Matter::SuperconductivityCondensed Matter::Strongly Correlated Electronsspin relaxationsuprajohteet
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