Spin-orbital entanglement and the breakdown of singlets and triplets in Sr 2RuO 4 revealed by spin- and angle-resolved photoemission spectroscopy
Spin-orbit coupling has been conjectured to play a key role in the low-energy electronic structure of Sr2RuO4. By using circularly polarized light combined with spin- and angle-resolved photoemission spectroscopy, we directly measure the value of the effective spin-orbit coupling to be 130±30 meV. T...
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
26 March 2014
|
| In: |
Physical review letters
Year: 2014, Volume: 112, Issue: 12, Pages: 127002 |
| ISSN: | 1079-7114 |
| DOI: | 10.1103/PhysRevLett.112.127002 |
| Online Access: | Verlag, Volltext: http://dx.doi.org/10.1103/PhysRevLett.112.127002 Verlag, Volltext: https://link.aps.org/doi/10.1103/PhysRevLett.112.127002 
|
| Author Notes: | C.N. Veenstra, Z.-H. Zhu, M. Raichle, B. M. Ludbrook, A. Nicolaou, B. Slomski, G. Landolt, S. Kittaka, Y. Maeno, J.H. Dil, I.S. Elfimov, M.W. Haverkort, and A. Damascelli |
| Summary: | Spin-orbit coupling has been conjectured to play a key role in the low-energy electronic structure of Sr2RuO4. By using circularly polarized light combined with spin- and angle-resolved photoemission spectroscopy, we directly measure the value of the effective spin-orbit coupling to be 130±30 meV. This is even larger than theoretically predicted and comparable to the energy splitting of the dxy and dxz,yz orbitals around the Fermi surface, resulting in a strongly momentum-dependent entanglement of spin and orbital character in the electronic wavefunction. As demonstrated by the spin expectation value ⟨→sk⋅→s−k⟩ calculated for a pair of electrons with zero total momentum, the classification of the Cooper pairs in terms of pure singlets or triplets fundamentally breaks down, necessitating a description of the unconventional superconducting state of Sr2RuO4 in terms of these newly found spin-orbital entangled eigenstates. |
|---|---|
| Item Description: | Die Ziffern 2 und 4 im Titel sind tiefgestellt Gesehen am 27.09.2017 |
| Physical Description: | Online Resource |
| ISSN: | 1079-7114 |
| DOI: | 10.1103/PhysRevLett.112.127002 |