https://scholar.dgist.ac.kr/handle/20.500.11750/10042 2026-11-11T11:31:05Z https://scholar.dgist.ac.kr/handle/20.500.11750/61118 Title: Remote Moire Modulation of Decoupled Dirac Subsystems in Twisted Trilayer Graphene Author(s): Kim, Dohun; Choe, Junsik; 조민서; Taniguchi, Takashi; Watanabe, Kenji; Cho, Gil Young; Kim, Youngwook Abstract: Moire superlattices are generally assumed to act only at the interface where lattice mismatch or twist occurs. Here, we study charge transport in large-angle helical twisted trilayer graphene, where interlayer tunneling is strongly reduced. When only the top monolayer graphene is aligned with hBN, the electronic response reorganizes into a moire-modulated monolayer and a remaining twisted bilayer graphene subsystem. Despite the absence of any explicit structural moire in the twisted bilayer, we observe satellite-like features in its electronic response that run parallel to the primary spectrum and are locked to the density scale of the hBN/graphene moire. These observations are consistent with a weak moire-periodic electrostatic perturbation generated at the aligned interface and sensed by a spatially separated Dirac subsystem, even in the absence of coherent interlayer coupling. 2026-09-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/61064 Title: Superconductivity proximate to non-Abelian fractional spin Hall insulator in twisted bilayer MoTe2 Author(s): Ahn, Cheong-Eung; Seo, Donghae; Lee, Gyeoul; Kim, Youngwook; Cho, Gil Young Abstract: Twisted bilayer MoTe2 near two-degree twists has emerged as a platform for exotic correlated topological phases, including ferromagnetism and a non-Abelian fractional spin Hall insulator. Here we reveal the unexpected emergence of an intervalley superconducting phase that intervenes between these two states in the half-filled second moiré bands. Using a continuum model and exact diagonalization, we identify superconductivity through multiple signatures: negative binding energy, a dominant pair-density eigenvalue, finite superfluid stiffness, and pairing symmetry consistent with a time-reversal-symmetric nodal extended s-wave state. Remarkably, our numerical calculation suggests a continuous transition between superconductivity and the non-Abelian fractional spin Hall insulator, in which topological order and symmetry evolve simultaneously, supported by an effective field-theory description. Notably, our field-theoretic analysis indicates that superconductivity is driven by the condensation of charge-e/2 self-bosonic non-Abelian anyons, thereby providing a concrete realization of anyon superconductivity. Complementarily, when approached from the normal metallic side, superconductivity instead emerges from a Kohn–Luttinger instability enabled by the non-uniform quantum geometry of the flat moiré bands. Our results establish higher moiré bands as fertile ground for intertwined superconductivity and topological order, and point to experimentally accessible routes for realizing superconductivity in twisted bilayer MoTe2. 2026-04-30T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60993 Title: Gate-Reconfigurable Single- and Double-Dot Transport in Trilayer MoSe2 Author(s): Lee, Seungwoo; Park, Minjun; 노윤상; An, Sung Jin; Kim, Soyun; 조민서; Kim, Dohun; Taniguchi, Takashi; Watanabe, Kenji; Jung, Minkyung; Kim, Youngwook Abstract: We report gate-controlled quantum-dot transport in a trilayer MoSe2 device that combines a graphite back gate beneath the active region, a separate global gate for conductive access regions, and local top finger gates. In the low-backgate regime, bias spectroscopy shows regular Coulomb-blockade diamonds characteristic of single-dot transport. As backgate is increased, additional low-bias structure develops beyond a simple single-dot pattern, indicating that the electrostatic landscape is reshaped and that a second dot becomes active in transport. In the higher-backgate regime, plunger-gate tuning and two-gate measurements establish a gate-reconfigurable double-dot configuration with two non-equivalent dots whose relative alignment and interdot coupling evolve with gate voltage. These results indicate that trilayer MoSe2 supports electrically reconfigurable single- and double-dot transport in the present device architecture. 2026-08-31T15:00:00Z https://scholar.dgist.ac.kr/handle/20.500.11750/60891 Title: Lessons from α-RuCl3 for pursuing quantum spin liquid physics in atomically thin materials Author(s): Ojeda-Aristizabal Claudia; Zheng Xiaohu; Xu Changsong; Nussinov Zohar; Motome Yukitoshi; Banerjee Arnab; Tsen Adam W.; Knap Michael; Du Rui-Rui; Joshi Gajadhar; Mounce Andy; Kim Youngwook; Hunt Benjamin M.; Shcherbakov Dmitry; Zhou Boyi; Jing Ran; Liu Mengkun; Zhao Hui; Claassen Martin; Erten Onur; Chen Yong P.; Henriksen Erik A. Abstract: Quantum spin liquids can arise from Kitaev magnetic interactions, and exhibit fractionalized excitations with the potential for a topological form of quantum computation. This review surveys recent experimental and theoretical progress on the pursuit of phenomena related to Kitaev magnetism in layered and exfoliatable materials, which offer numerous opportunities to apply powerful techniques from the field of atomically thin materials. We primarily focus on the antiferromagnetic Mott insulator alpha-RuCl3, which exhibits Kitaev couplings and is readily exfoliated to single- or few-layer sheets, and thus serves as a test bed for developing probes of Kitaev phenomena in atomically thin materials and devices. We introduce the Kitaev model and how it is realized in alpha-RuCl3 and other material candidates; and cover alpha-RuCl3 synthesis and fabrication into van der Waals heterostructure devices. A key discovery is a work-function-mediated charge transfer that heavily dopes both the alpha-RuCl3 and proximate materials, and can enhance Kitaev interactions by up to 50%. We further discuss a wide range of recent results in electronic transport and optical and tunneling spectroscopies of alpha-RuCl3 devices. The experimental techniques and theoretical insights developed for alpha-RuCl3 establish a framework for discovering and engineering superior two-dimensional Kitaev materials that may ultimately realize elusive quantum spin liquid phases. 2026-06-30T15:00:00Z