CM Seminar - The puzzling superconducting order parameter of Sr2RuO4

Event Date:
2021-02-04T10:00:00
2021-02-04T11:00:00
Event Location:
Zoom link in description
Speaker:
Speaker: Aline Ramires (Paul Scherrer Institute)
Related Upcoming Events:
Intended Audience:
Public
Event Information:

https://ubc.zoom.us/j/64183011430?pwd=U2lFNXEwSmlBRWVBdTR5OG1ZdlVSZz09
Meeting ID: 641 8301 1430
Passcode: 113399


Strontium ruthenate has long been thought to host a spin-triplet chiral p-wave superconducting state. However, the singlet-like response observed in recent spin-susceptibility measurements casts serious doubts on this pairing state. Together with the evidence for broken time-reversal symmetry and a jump in the shear modulus c66 at the superconducting transition temperature, the newly available experiments point towards an even-parity chiral superconductor. Here, we show how the orbital degree of freedom can encode the two-component nature of this order parameter, allowing for a local orbital-antisymmetric spin-triplet state that is favored by strong Hund’s coupling. We find that this exotic state can be energetically stable once a complete, realistic three-dimensional model is considered. We highlight how the concept of superconducting fitness was used in order to guide our search in parameter space and to discuss how momentum-dependent spin-orbit coupling terms are key.

Add to Calendar 2021-02-04T10:00:00 2021-02-04T11:00:00 CM Seminar - The puzzling superconducting order parameter of Sr2RuO4 Event Information: https://ubc.zoom.us/j/64183011430?pwd=U2lFNXEwSmlBRWVBdTR5OG1ZdlVSZz09Meeting ID: 641 8301 1430Passcode: 113399 Strontium ruthenate has long been thought to host a spin-triplet chiral p-wave superconducting state. However, the singlet-like response observed in recent spin-susceptibility measurements casts serious doubts on this pairing state. Together with the evidence for broken time-reversal symmetry and a jump in the shear modulus c66 at the superconducting transition temperature, the newly available experiments point towards an even-parity chiral superconductor. Here, we show how the orbital degree of freedom can encode the two-component nature of this order parameter, allowing for a local orbital-antisymmetric spin-triplet state that is favored by strong Hund’s coupling. We find that this exotic state can be energetically stable once a complete, realistic three-dimensional model is considered. We highlight how the concept of superconducting fitness was used in order to guide our search in parameter space and to discuss how momentum-dependent spin-orbit coupling terms are key. Event Location: Zoom link in description