Twisted van der Waals Quantum Materials: Fundamentals, Tunability, and Applications

Chemical Reviews, Год журнала: 2024, Номер 124(4), С. 1992 - 2079

Опубликована: Фев. 9, 2024

Twisted van der Waals (vdW) quantum materials have emerged as a rapidly developing field of two-dimensional (2D) semiconductors. These establish new central research area and provide promising platform for studying phenomena investigating the engineering novel optoelectronic properties such single photon emission, nonlinear optical response, magnon physics, topological superconductivity. captivating electronic result from, can be tailored by, interlayer coupling using moiré patterns formed by vertically stacking atomic layers with controlled angle misorientation or lattice mismatch. Their outstanding high degree tunability position them compelling building blocks both compact quantum-enabled devices classical optoelectronics. This paper offers comprehensive review recent advancements in understanding manipulation twisted structures presents survey state-of-the-art on superlattices, encompassing interdisciplinary interests. It delves into fundamental theories, synthesis fabrication, visualization techniques, wide range physical exhibited these structures, focus their potential practical device integration applications ranging from information to biosensors, including optoelectronics modulators, light emitting diodes, lasers, photodetectors. highlights unique ability superlattices connect multiple disciplines, covering chemistry, electronics, optics, photonics, magnetism, physics. provides valuable resource researchers interested shedding characteristics transformative various fields.

Язык: Английский

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Exciton optics, dynamics, and transport in atomically thin semiconductors

APL Materials, Год журнала: 2022, Номер 10(10)

Опубликована: Окт. 1, 2022

Atomically thin semiconductors such as transition metal dichalcogenide (TMD) monolayers exhibit a very strong Coulomb interaction, giving rise to rich exciton landscape. This makes these materials highly attractive for efficient and tunable optoelectronic devices. In this article, we review the recent progress in understanding of optics, dynamics transport, which crucially govern operation TMD-based We highlight impact hBN-encapsulation, reveals plethora many-particle states optical spectra, outline most novel breakthroughs field exciton-polaritonics. Moreover, underline direct observation formation thermalization TMD heterostructures time-resolved ARPES studies. also show density, strain dielectric environment on diffusion funneling. Finally, put forward relevant research directions atomically near future.

Язык: Английский

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Strain Engineering of Twisted Bilayer Graphene: The Rise of Strain‐Twistronics

Small, Год журнала: 2024, Номер unknown

Опубликована: Апрель 15, 2024

Abstract The layer‐by‐layer stacked van der Waals structures (termed vdW hetero/homostructures) offer a new paradigm for materials design—their physical properties can be tuned by the vertical stacking sequence as well adding mechanical twist, stretch, and hydrostatic pressure to atomic structure. In particular, simple twisting of two layers graphene form uniform ordered Moiré superlattice, which effectively modulate electrons lead discovery unconventional superconductivity strong correlations. However, twist angle twisted bilayer (tBLG) is almost unchangeable once interlayer determined, while applying elastic strain provides an alternative way deeply regulate electronic structure controlling lattice spacing symmetry. this review, diverse experimental advances are introduced in straining tBLG in‐plane out‐of‐plane modes, followed characterizations calculations toward quantitatively tuning strain‐engineered structures. It further discussed that structural relaxation strained superlattice its influence on Finally, conclusion entails prospects opportunities 2D materials, discussions existing challenges, outlook intriguing emerging field, namely “strain‐twistronics”.

Язык: Английский

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Twisted oxide membranes: A perspective

APL Materials, Год журнала: 2024, Номер 12(1)

Опубликована: Янв. 1, 2024

Freestanding oxide membranes have recently emerged as a promising platform, offering new opportunities for experimentalists to design materials with novel properties. These membranes, typically consisting of transition metal oxides, can be synthesized freestanding ultra-thin quasi-2D layers and, subsequently, reassembled into multilayer stacks controlled relative twist angles. In these heterostructures, controlling the moiré superlattices pattern two lattices play crucial role in creating unique and electronic, optical, magnetic, mechanical properties that do not exist individual constituent or traditional non-twisted epitaxial heterostructures. Here, we explore stacking twisting including underlying principles potential applications. We also discuss current challenges provide perspective on some possible future directions field. Our aim is highlight functional by membranes.

Язык: Английский

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Strong light-matter coupling in van der Waals materials

Light Science & Applications, Год журнала: 2024, Номер 13(1)

Опубликована: Авг. 21, 2024

In recent years, two-dimensional (2D) van der Waals materials have emerged as a focal point in research, drawing increasing attention due to their potential for isolating and synergistically combining diverse atomic layers. Atomically thin transition metal dichalcogenides (TMDs) are one of the most alluring owing exceptional electronic optical properties. The tightly bound excitons with giant oscillator strength render TMDs an ideal platform investigate strong light-matter coupling when they integrated cavities, providing wide range possibilities exploring novel polaritonic physics devices. this review, we focused on advances TMD-based coupling. foremost position, discuss various structures strongly coupled TMD materials, such Fabry-Perot photonic crystals, plasmonic nanocavities. We then present several intriguing properties relevant device applications polaritons. end, delineate promising future directions study materials.

Язык: Английский

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Electrical tuning of moiré excitons in MoSe₂ bilayers

2D Materials, Год журнала: 2022, Номер 10(1), С. 014013 - 014013

Опубликована: Дек. 7, 2022

Recent advances in the field of vertically stacked 2D materials have revealed a rich exciton landscape. In particular, it has been demonstrated that out-of-plane electrical fields can be used to tune spectral position spatially separated interlayer excitons. Other studies shown there is strong hybridization states, resulting from mixing electronic states both layers. However, connection between twist-angle dependent and field-induced energy shifts remained dark. Here, we investigate on microscopic footing interplay tuning moir\'e excitons MoSe$_2$ homobilayers. We reveal distinct regions PL spectra are clearly dominated by either intralayer or excitons, even dark Consequently, predict twist-angle-dependent critical at which material being transformed direct into an indirect semiconductor. Our work provides new insights experimentally accessible knobs significantly physics atomically thin nanomaterials.

Язык: Английский

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Twistronics and moiré excitonic physics in van der Waals heterostructures

Frontiers of Physics, Год журнала: 2024, Номер 19(4)

Опубликована: Март 1, 2024

Abstract Heterostructures composed of two-dimensional van der Waals (vdW) materials allow highly controllable stacking, where interlayer twist angles introduce a continuous degree freedom to alter the electronic band structures and excitonic physics. Motivated by discovery Mott insulating states superconductivity in magic-angle bilayer graphene, emerging research fields “twistronics” moiré physics have aroused great academic interests engineering optoelectronic properties exploration new quantum phenomena, which superlattice provides pathway for realization artificial crystals. Here we systematically summarize current achievements twistronics physics, with emphasis on roles lattice rotational mismatches atomic registries. Firstly, review effects photonic particularly exciton such as dipole moment spin-valley polarization, through interactions structures. We also discuss dynamics vdW heterostructures different angles, like formation, transport relaxation processes, whose mechanisms are complicated still need further investigations. Subsequently, theoretical analysis experimental observations modulated excitons. Various exotic shown, including periodic potential, miniband, varying wave function symmetry, result localization, emergent peaks spatially alternating optical selection rule. expanded systems external modulation factors electric field, doping strain, showing that is promising platform high tunability applications in-depth study frontier Lastly, focus rapidly developing field correlated electron based system, potentially related phenomena.

Язык: Английский

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Circumventing the polariton bottleneck via dark excitons in 2D semiconductors

Optica, Год журнала: 2024, Номер 11(9), С. 1346 - 1346

Опубликована: Июль 24, 2024

Efficient scattering into the exciton polariton ground state is a key prerequisite for generating Bose–Einstein condensates and low-threshold lasing. However, this can be challenging to achieve at low densities due bottleneck effect that impedes phonon-driven low-momentum states. The rich landscape of transition metal dichalcogenides (TMDs) provides potential intervalley pathways via dark excitons rapidly populate these polaritons. Here, we present theoretical fully microscopic study exploring time- momentum-resolved relaxation polaritons supported by MoSe 2 monolayer integrated within Fabry–Perot cavity. By exploiting phonon-assisted transitions between momentum-dark lower branch, demonstrate it possible circumvent region efficiently state. Furthermore, pathway predicted give rise to, yet unobserved, angle-resolved phonon sidebands in low-temperature photoluminescence spectra are associated with excitons. This represents distinct signature efficient phonon-mediated polariton-dark-exciton interactions.

Язык: Английский

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Insight into exciton polaritons of two-dimensional transition metal dichalcogenides with time-resolved spectroscopy

MRS Communications, Год журнала: 2025, Номер unknown

Опубликована: Янв. 21, 2025

Язык: Английский

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Magneto-Optics of Anisotropic Exciton Polaritons in Two-Dimensional Perovskites

Nano Letters, Год журнала: 2025, Номер unknown

Опубликована: Май 13, 2025

Layered two-dimensional (2D) organic-inorganic perovskite semiconductors support strongly confined excitons that offer significant potential for ultrathin polaritonic devices due to their tunability and huge oscillator strength. The application of a magnetic field has proven be an invaluable tool investigating the exciton fine structure observed in these materials, yet combination in-plane strong coupling regime remained largely unexplored. In this work, we combine microscopic theory with rigorous solution Maxwell's equations model magneto-optics polaritons 2D perovskites. We predict brightened dark state can enter regime. Furthermore, magnetic-field-induced mixing polarization selection rules breaking symmetry lead highly anisotropic polariton branches. This study contributes better understanding perovskites demonstrates cavity control polarization-sensitive polaritons.

Язык: Английский

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