*

Spin-triplet topological superconductors should exhibit many unprecedented electronic properties including fractionalized electronic states relevant to quantum information processing. Although UTe₂ may embody such bulk topological superconductivity its superconductive order-parameter  remains unknown. Moreover, intertwined density waves of spin (SDW), charge (CDW) and pairs (PDW) may interpose, with the latter exhibiting spatially modulating superconductive order-parameter , electron pair density and pairing energy-gap. Hence, the newly discovered CDW state in UTe₂ (1) motivates the prospect that a PDW state could exist in this material. To search for it, we visualize the pairing energy-gap with  energy-resolution using superconductive STM tips. We detect three PDWs, each with peak-peak gap modulations circa  and at incommensurate wavevectors  that are indistinguishable from the wavevectors  of the prevenient CDW. Concurrent visualization of the UTe₂ superconductive PDWs and the non-superconductive CDWs reveals that every  pair exhibits a relative spatial phase  From these observations and given UTe₂ as a spin-triplet superconductor_, this PDW state should be a spin-triplet pair density wave (2).

References

1.  A. Aishwarya, J. May-mann, A. Raghavan, L. Nie, M. Romanelli, Magnetic-field-sensitive charge density waves in the superconductor UTe 2. Nature. 618 (2023). 

2. Q. Gu+, J. P. Carroll+, S. Wang+, S. Ran, C. Broyles, H. Siddiquee, N. P. Butch, S. R. Saha, J. Paglione, J. C. S. Davis, X. Liu, Detection of a Pair Density Wave State in UTe2. Nature. 618, 921 (2023).