Microscopic mechanism of unconventional superconductivity in twisted 2D materials

Determine the microscopic mechanism and superconducting phase characteristics (including pairing symmetry and ground state) of unconventional superconductivity in twisted two-dimensional materials such as twisted bilayer graphene and twisted transition‑metal dichalcogenides, in order to resolve the outstanding open questions surrounding their superconducting state.

Background

Twisting stacked two-dimensional materials creates moiré superlattices that profoundly modify their electronic structure and can drive correlated phases such as superconductivity. Despite extensive theoretical activity, the precise nature of superconductivity in twisted 2D materials—its origin, symmetry, and microscopic pairing mechanism—remains unsettled.

Clarifying the microscopic mechanism and the superconducting phase properties is central to interpreting existing experiments and to guiding future materials design and device applications, including quantum technologies and plasmonic manipulation of collective modes in correlated states.

References

The field of twisted 2D materials has grown rapidly in recent years, presenting new challenges to the scientific community, and leaving many open questions. One of the most compelling challenges is the microscopic explanation of unconventional superconductivity in twisted 2D materials. Despite numerous theoretical proposals, the nature of the superconducting phase in these systems remains elusive.

— Roadmap for Photonics with 2D Materials  (2504.04558 - Abajo et al., 6 Apr 2025) in Section 4.2, Challenges and Future Goals

Whether pairing is intrinsically disfavored in twisted multilayers, or has simply not been found under the right conditions, remains an open question.

— Incipient superconductivity and tunable Chern insulators in twisted Bernal bilayer-trilayer graphene  (2609.30202 - Waleffe et al., 24 Sep 2026) in Introduction

The order responsible for the insulator, and the origin of the enhanced $T_c$ near its boundary, remain to be determined.

— Incipient superconductivity and tunable Chern insulators in twisted Bernal bilayer-trilayer graphene  (2609.30202 - Waleffe et al., 24 Sep 2026) in Discussion

The halo is therefore stable over a range of angles and across the twisted Bernal family, while the conditions under which it also supports pairing remain to be identified.

— Incipient superconductivity and tunable Chern insulators in twisted Bernal bilayer-trilayer graphene  (2609.30202 - Waleffe et al., 24 Sep 2026) in Discussion

Directly resolving SC at half-filling with unbiased numerics remains an important open question.

— Chiral spin liquid and chiral antiferromagnetism in half-filled moiré Hubbard model: possible applications to twisted bilayer TMDs  (2608.14503 - Tuo et al., 14 Aug 2026) in Discussion