64 citations · 272 across the 22 of their papers we have counts for
24 papers
Extended s-wave superconductivity in M-point twisted bilayer SnSe2
Lennart Klebl, Ammon Fischer, Salahudin V. Smailagić +6
We investigate the emergence of electronic order and unconventional superconductivity in M-valley moiré materials. Starting from a first-principles Wannier model of AB-stacked twis…
Organizing Principles for Moiré Quantum Matter
Qiaoling Xu, Yifan Gao, Tao Zhang +16
Moiré flat bands in van der Waals bilayers are usually discussed through a small set of mechanisms associated with the and valleys of hexagonal crystals, and more recently…
Feasibility study of continuous electronic Pomeranchuk cooling with a flavor-degenerate Wigner crystal
Robin J. Dolleman, Ammon Fischer, Lennart Klebl +5
Achieving sub-millikelvin electron temperatures in nanoelectronic devices could unveil new transport phenomena, extend quantum coherence times, and enhance the precision of quantum…
Correlation-Driven Ballistic Exciton Expansion in a Moiré Bose-Fermi Mixture
Shibin Deng, Jonas M. Peterson, Maximilian Hauer +8
Moiré superlattices of transition-metal dichalcogenides (TMDs) host strongly interacting Bose-Fermi mixtures in which bosonic excitons coexist with correlated electron lattices. Us…
Angle evolution of the superconducting phase diagram in twisted bilayer WSe2
Yinjie Guo, John Cenker, Ammon Fischer +13
Recent observations of superconductivity in twisted bilayer WSe have extended the family of moiré superconductors beyond twisted graphene. In WSe two different twist angles…
Floquet Engineering Magnetism and Superconductivity in the Square-Lattice Hubbard Model
Jan-Niklas Herre, Takuya Okugawa, Ammon Fischer +2
We study the interplay of magnetic order and superconductivity in the square-lattice Hubbard model under periodic driving with circularly polarized light. Formulating diagrammatic…
Magnetic Ordering in Moiré Graphene Multilayers from a Continuum Hartree+U Approach
Christopher T. S. Cheung, Valerio Vitale, Lennart Klebl +5
Recently, symmetry-broken ground states, such as correlated insulating states, magnetic order and superconductivity, have been discovered in twisted bilayer graphene (tBLG) and twi…
Emergent Interacting Phases in the Strong Coupling Limit of Twisted M-Valley Moiré Systems: Application to SnSe
Ming-Rui Li, Dumitru Calugaru, Yi Jiang +10
We construct an interacting Wannier model for both AA-stacked and AB-stacked twisted SnSe2, revealing a rich landscape of correlated quantum phases. For the AA-stacked case, the sy…
Site-polarized Mott phases competing with a correlated metal in twisted WSe
Siheon Ryee, Lennart Klebl, Gautam Rai +9
Twisted WSe hosts superconductivity, metal-insulator phase transitions, and field-controllable Fermi-liquid to non-Fermi-liquid transport properties. In this work, we use dynam…
Quantum melting of generalized electron crystal in twisted bilayer MoSe2
Qi Jun Zong, Haolin Wang, Qi Zhang +12
Electrons can form an ordered solid crystal phase ascribed to the interplay between Coulomb repulsion and kinetic energy. Tuning these energy scales can drive a phase transition fr…
Theory of intervalley-coherent AFM order and topological superconductivity in tWSe
Ammon Fischer, Lennart Klebl, Valentin Crépel +7
The recent observation of superconductivity in the vicinity of Fermi surface reconstructed insulating or metallic states has established twisted bilayers of WSe\textsubscript{2} as…
Gate-defined single-electron transistors in twisted bilayer graphene
Alexander Rothstein, Ammon Fischer, Anthony Achtermann +12
Twisted bilayer graphene (tBLG) near the magic angle is a unique platform where the combination of topology and strong correlations gives rise to exotic electronic phases. These ph…
Supercell Wannier functions and a faithful low-energy model for Bernal bilayer graphene
Ammon Fischer, Lennart Klebl, Dante M. Kennes +1
We derive a minimal low-energy model for Bernal bilayer graphene and related rhombohedral graphene multilayers at low electronic densities by constructing Wannier orbitals defined…
Engineering 2D square lattice Hubbard models in 90 twisted Ge/SnX (X=S, Se) moiré supperlattices
Qiaoling Xu, Ammon Fischer, Nicolas Tancogne-Dejean +6
Due to the large-period superlattices emerging in moire two-dimensional (2D) materials, electronic states in such systems exhibit low energy flat bands that can be used to simulate…
Negative electronic compressibility in charge islands in twisted bilayer graphene
Robin J. Dolleman, Alexander Rothstein, Ammon Fischer +8
We report on the observation of negative electronic compressibility in twisted bilayer graphene for Fermi energies close to insulating states. To observe this negative compressibil…
Phonon-mediated unconventional - and -wave pairing superconductivity in rhombohedral stacked multilayer graphene
Emil Viñas Boström, Ammon Fischer, Jonas B. Profe +3
Understanding the origin of superconductivity in correlated two-dimensional materials is a key step in leveraging material engineering techniques for next-generation nanoscale devi…
Spin and Charge Fluctuation Induced Pairing in ABCB Tetralayer Graphene
Ammon Fischer, Lennart Klebl, Jonas B. Profe +5
Motivated by the recent experimental realization of ABCB stacked tetralayer graphene [Wirth et al., ACS Nano 16, 16617 (2022)], we study correlated phenomena in moiré-less graphene…
Moiré Engineering of Nonsymmorphic Symmetries and Hourglass Superconductors
Yifan Gao, Ammon Fischer, Lennart Klebl +5
Moiré heterostructures hold the promise to provide platforms to tailor strongly correlated and topological states of matter. Here, we theoretically propose the emergence of an effe…
Competition of Density Waves and Superconductivity in Twisted Tungsten Diselenide
Lennart Klebl, Ammon Fischer, Laura Classen +2
Evidence for correlated insulating and superconducting phases around regions of high density of states was reported in the strongly spin-orbit coupled van-der Waals material twiste…
Experimental observation of ABCB stacked tetralayer graphene
Konstantin G. Wirth, Jonas B. Profe, Alexander Rothstein +10
In tetralayer graphene, three inequivalent layer stackings should exist, however, only rhombohedral (ABCA) and Bernal (ABAB) stacking have so far been observed. The three stacking…
Moiré Engineering of Spin-Orbit Coupling in Twisted Platinum Diselenide
Lennart Klebl, Qiaoling Xu, Ammon Fischer +4
We study the electronic structure and correlated phases of twisted bilayers of platinum diselenide using large-scale ab initio simulations combined with the functional renormalizat…
Unconventional Superconductivity in Magic-Angle Twisted Trilayer Graphene
Ammon Fischer, Zachary A. H. Goodwin, Arash A. Mostofi +3
Magic-angle twisted trilayer graphene (MATTG) recently emerged as a highly tunable platform for studying correlated phases of matter, such as correlated insulators and superconduct…
Engineering Three Dimensional Moiré Flat Bands
Lede Xian, Ammon Fischer, Martin Claassen +3
We demonstrate that the concept of moiré flat bands can be generalized to achieve electronic band engineering in all three spatial dimensions. For many two dimensional van der Waal…
Spin-fluctuation-induced pairing in twisted bilayer graphene
Ammon Fischer, Lennart Klebl, Carsten Honerkamp +1
We investigate the interplay of magnetic fluctuations and Cooper pairing in twisted bilayer graphene from a purely microscopic model within a large-scale tight-binding approach res…