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DOE OSTI · 2367317

Singlet, triplet, and pair density wave superconductivity in the doped triangular-lattice moiré system

Chen, Feng·Sheng, D. N.
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Abstract

Recent experimental progress has established the twisted bilayer transition metal dichalcogenide (TMD) as a highly tunable platform for studying many-body physics. Particularly, the homobilayer TMDs under displacement field are believed to be described by a generalized triangular-lattice Hubbard model with a spin-dependent hopping phase θ. To explore the effects of θ on the system, we perform density matrix renormalization group calculations for the relevant triangular lattice t-J model. By changing θ at small hole doping, we obtain a region of quasi-long-range superconducting order coexisting with charge and spin density wave within 0 < θ < π/3. The superconductivity is composed of a dominant spin singlet d-wave and a subdominant triplet p-wave pairing. Intriguingly, the S z = ±1 triplet pairing components feature pair-density waves. In addition, we find a region of triplet superconductivity coexisting with charge-density wave and ferromagnetism within π/3 < θ < 2π/3, which is related to the former phase at smaller θ by a combined operation of spin-flip and gauge transformation. Furthermore, our findings provide insights and directions for experimental search for exotic superconductivity in twisted TMD systems.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYDensity matrix renormalization groupSuperconducting order parameterTransition metal dichalcogenidesTwisted heterostructures

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BibTeXRIS

Chen, Feng, Sheng, D. N.. 2023-11-13. Singlet, triplet, and pair density wave superconductivity in the doped triangular-lattice moiré system. https://doi.org/10.1103/physrevb.108.l201110

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