TY - JOUR
T1 - Evening out the spin and charge parity to increase T
c in Sr
2RuO
4
AU - Acharya, Swagata
AU - Pashov, Dimitar Lyubomirov
AU - Weber, Cedric Raphael
AU - Park, Hyowon
AU - Sponza, Lorenzo
AU - Van Schilfgaarde, Mark
PY - 2019/12/17
Y1 - 2019/12/17
N2 - Unconventional superconductivity in Sr
2RuO
4 has been intensively studied for decades. However, the nature of pairing continues to be widely debated. Here we develop a detailed ab initio theory, coupling quasiparticle self-consistent GW approximation with dynamical mean field theory (DMFT), including both local and non-local correlations to address the subtle interplay among spin, charge and orbital degrees of freedom. We report that the superconducting instability has multiple triplet and singlet components. In the unstrained case the triplet eigenvalues are larger than the singlets. Under uniaxial strain, the triplet eigenvalues drop and the singlet components increase. This is concomitant with our observation of spin and charge fluctuations shifting closer to wave-vectors favoring singlet pairing. We identify a complex mechanism where charge fluctuations and spin fluctuations co-operate in the even-parity channel under strain leading to increment in critical temperature (Tc), thus proposing a novel mechanism for pushing the frontier of critical temperature (Tc) in unconventional ‘triplet’ superconductors.
AB - Unconventional superconductivity in Sr
2RuO
4 has been intensively studied for decades. However, the nature of pairing continues to be widely debated. Here we develop a detailed ab initio theory, coupling quasiparticle self-consistent GW approximation with dynamical mean field theory (DMFT), including both local and non-local correlations to address the subtle interplay among spin, charge and orbital degrees of freedom. We report that the superconducting instability has multiple triplet and singlet components. In the unstrained case the triplet eigenvalues are larger than the singlets. Under uniaxial strain, the triplet eigenvalues drop and the singlet components increase. This is concomitant with our observation of spin and charge fluctuations shifting closer to wave-vectors favoring singlet pairing. We identify a complex mechanism where charge fluctuations and spin fluctuations co-operate in the even-parity channel under strain leading to increment in critical temperature (Tc), thus proposing a novel mechanism for pushing the frontier of critical temperature (Tc) in unconventional ‘triplet’ superconductors.
UR - http://www.scopus.com/inward/record.url?scp=85076617697&partnerID=8YFLogxK
U2 - 10.1038/s42005-019-0254-1
DO - 10.1038/s42005-019-0254-1
M3 - Article
SN - 2399-3650
VL - 2
JO - Communications Physics
JF - Communications Physics
IS - 1
M1 - 163
ER -