TY - JOUR
T1 - Coherent Superconductivity with a Large Gap Ratio from Incoherent Metals
AU - Patel, Aavishkar A.
AU - Lawler, Michael J.
AU - Kim, Eun Ah
N1 - Publisher Copyright:
© 2018 American Physical Society.
PY - 2018/10/30
Y1 - 2018/10/30
N2 - A mysterious incoherent metallic (IM) normal state with T-linear resistivity is ubiquitous among strongly correlated superconductors. Recent progress with microscopic models exhibiting IM transport has presented the opportunity for us to study new models that exhibit direct transitions into a superconducting state out of IM states within the framework of connected Sachdev-Ye-Kitaev "quantum dots." Here, local Sachdev-Ye-Kitaev interactions within a dot produce IM transport in the normal state, while local attractive interactions drive superconductivity. Through explicit calculations, we find two features of superconductivity arising from an IM normal state. First, despite the absence of quasiparticles in the normal state, the superconducting state still exhibits coherent superfluid transport. Second, the nonquasiparticle nature of the IM Green's functions produces a large enhancement in the ratio of the zero-temperature superconducting gap Δ and transition temperature TSC, 2Δ/TSC, with respect to its BCS value of 3.53.
AB - A mysterious incoherent metallic (IM) normal state with T-linear resistivity is ubiquitous among strongly correlated superconductors. Recent progress with microscopic models exhibiting IM transport has presented the opportunity for us to study new models that exhibit direct transitions into a superconducting state out of IM states within the framework of connected Sachdev-Ye-Kitaev "quantum dots." Here, local Sachdev-Ye-Kitaev interactions within a dot produce IM transport in the normal state, while local attractive interactions drive superconductivity. Through explicit calculations, we find two features of superconductivity arising from an IM normal state. First, despite the absence of quasiparticles in the normal state, the superconducting state still exhibits coherent superfluid transport. Second, the nonquasiparticle nature of the IM Green's functions produces a large enhancement in the ratio of the zero-temperature superconducting gap Δ and transition temperature TSC, 2Δ/TSC, with respect to its BCS value of 3.53.
UR - http://www.scopus.com/inward/record.url?scp=85056081799&partnerID=8YFLogxK
U2 - 10.1103/PhysRevLett.121.187001
DO - 10.1103/PhysRevLett.121.187001
M3 - Article
C2 - 30444391
AN - SCOPUS:85056081799
SN - 0031-9007
VL - 121
JO - Physical Review Letters
JF - Physical Review Letters
IS - 18
M1 - 187001
ER -