Distinct moiré exciton dynamics in WS2/WSe2 heterostructure

Quantum Frontiers, Journal Year: 2025, Volume and Issue: 4(1)

Published: Feb. 6, 2025

Abstract This letter reports a time resolved pump-probe reflectance spectroscopic study on moiré excitons in twisted monolayer WS 2 /WSe heterostructure. By probing at the resonant energies of intralayer excitons, we observed their distinct temporal tracks under influence interlayer which attribute to discrepancy spatial distribution different layers. We also that WSe layer differ decay rate, reflects locations Wannier-like and charge-transfer cell. concluded form within few picoseconds have lifetime exceeding five nanoseconds. Our results provide insights into nature strain’s significant impact behaviour heterostructures, could important implications for development novel optoelectronic devices.

Language: Английский

---

Superradiance of Strongly Interacting Dipolar Excitons in Moiré Quantum Materials

Physical Review Letters, Journal Year: 2025, Volume and Issue: 134(12)

Published: March 26, 2025

Moiré lattices created in two-dimensional heterostructures exhibit rich many-body physics of interacting electrons and excitons and, at the same time, suggest promising optoelectronic applications. Here, we study cooperative radiance moiré that is demonstrated to emerge from deep subwavelength nature lattice strong excitonic on-site interaction. In particular, show static dipole-dipole interaction between interlayer can strongly affect their optical properties, suppressing superradiance disordered states while enhancing ordered phases excitons. Moreover, doping permits direct control cooperativity, e.g., by generating superradiant dynamics otherwise subradiant Our results offer a unique platform for exploring phenomena systems, thus holding promise applications quantum nonlinear optics. Published American Physical Society 2025

Language: Английский

---

Optical Microcavity‐Induced Moiré Exciton Localization in Twisted WSe₂ Homobilayer

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: April 2, 2024

Abstract 2D moiré superlattices offer a versatile platform for manipulating quantum materials, exploiting their spatially varying atomic registry to modify electronic structures, resulting in the emergence of flat minibands, enhanced interactions, and onset novel phenomena. Despite extensive investigations into excitons within twisted bilayer superlattices, interplay between optical microcavities remains elusive. Here, WSe 2 homobilayer with small twist angle positioned on atop SiO (285 nm)/Si substrate is investigated. Utilizing low‐temperature photoluminescence (PL) spectroscopy, it observed that at edge cavity (Edge‐THB) exhibits localization deeper potential. This behavior attributed combined influence strain induced by microcavity structure superlattice amplification electromagnetic field. Furthermore, existence through comprehensive analysis, encompassing temperature‐dependent PL spectra, circularly polarized Landé g‐factor measurements Edge‐THB validated. These findings provide valuable insights intricate interaction microcavities, paving way future applications technologies.

Language: Английский

---

Insulator phases of Bose-Fermi mixtures induced by intraspecies next-neighbor interactions

SciPost Physics Core, Journal Year: 2025, Volume and Issue: 8(1)

Published: Jan. 21, 2025

We study a one-dimensional mixture of two-color fermions and scalar bosons at the hardcore limit, focusing on effect that intraspecies next-neighbor interactions have zero-temperature ground state system for different fillings each carrier. Exploring problem’s parameters, we observed nearest-neighbor interaction could favor or harm well-known mixed Mott spin-selective insulators. also found emergence three unusual insulating states with charge density wave (CDW) structures in which orders carriers are out phase between other. For instance, immiscible CDW appears only half-filling bosonic density, whereas is characterized by equal densities fermions. Finally, couples one kind Appropriate order parameters were proposed to obtain critical corresponding superfluid-insulator transition. Our results can inspire contribute understanding experiments cold-atom setups long-range recent reports involving quasiparticles semiconductor heterostructures.

Language: Английский

---

Twisted Bilayer MXenes//MoS₂ Moiré Superlattices for Alkaline Metal-Ion Batteries: Insights from First-Principles Calculations

The Journal of Physical Chemistry C, Journal Year: 2025, Volume and Issue: unknown

Published: March 22, 2025

Language: Английский

---

Tuning Transport in Solid-State Bose-Fermi Mixtures by Feshbach Resonances

Physical Review Letters, Journal Year: 2025, Volume and Issue: 134(12)

Published: March 26, 2025

Transition-metal-dichalcogenide heterostructures have emerged as promising platforms for realizing tunable Bose–Fermi mixtures. Their constituents are fermionic charge carriers resonantly coupled to long-lived bosonic interlayer excitons, allowing them form trion bound states. Such promise achieve comparable densities of fermions and bosons at low relative temperatures. Here, we predict the transport properties correlated mixtures close a narrow solid-state Feshbach resonance. When driving hole current, responses doped holes, trions significantly modified by resonant interactions, leading deviations from typical Drude behavior sign change exciton drag. Our results on temperature-dependent resistivities demonstrate that near resonance interaction effects dominate over established conventional scattering mechanisms in these Published American Physical Society 2025

Language: Английский

---

ac Stark Spectroscopy of Interactions between Moiré Excitons and Polarons

Physical Review X, Journal Year: 2025, Volume and Issue: 15(2)

Published: April 1, 2025

We use nonlinear pump-probe spectroscopy to study optical excitations in a charge-tunable MoSe2/WS2 moiré heterostructure. An intense red-detuned laser pulse creates photonic dressing of the material by introducing large population excitons or exciton polarons deep potential. By measuring resulting ac Stark effect with weak resonant pulse, we gain access nature and mutual interactions elementary excitations. At charge neutrality, our measurements reveal that different resonances, associated confinement their center-of-mass motion potential, have significant spatial overlap. The short-range manifest themselves as density-dependent blueshift for same-valley bound biexciton states opposite-valley excitons. attractive polaron resonance appears upon injection electrons into heterostructure shows contrasting behavior: Here, observe an electron-density-independent light shift clear pump-power-dependent saturation. These features are equivalent ensemble independent two-level emitters indicate breakdown Fermi-polaron picture subject strong Our work establishes experimental approach elucidate semiconductor heterostructures, providing solid ground correlated electronic excitonic such materials. Published American Physical Society 2025

Language: Английский

---

Magneto-Polarization Controlled by Intervalley Scattering of Interlayer Excitons and Carriers in WS₂/WSe₂ Heterostructure

Nano Letters, Journal Year: 2025, Volume and Issue: unknown

Published: April 11, 2025

The photoluminescence polarization of interlayer excitons (IXs) offers a powerful tool for exploring moiré physics transition metal dichalcogenide (TMD) heterostructures. However, in WS2/WSe2 heterostructures, this is often weak and the underlying mechanism intervalley scattering remains unclear. Notably, closeness IX lifetime carrier valley complicates investigation process. Here, we demonstrate that magnetic fields can sensitively tune dynamics both carriers We find small suppress scattering, significantly enhancing polarization, whereas at higher fields, emission largely controlled by electrons, leading to excitation-dependent saturation effects. Our results highlight interplay between exciton behaviors tailoring offering potential pathways design valleytronic devices leveraging TMD

Language: Английский

---

Correlated fermionic-bosonic insulating states in twisted hetero-trilayer semiconductors

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: April 26, 2025

Correlated insulating states such as fermionic and bosonic insulators have been observed individually in transition metal dichalcogenide heterostructures. However, the interplay between correlated their dynamical evolution on a single system, remain largely unexplored. Here, we demonstrate that twisted trilayer heterostructures host an unconventional complex, namely charge-layer-locked trion with symmetric charge configuration. Owing to its spatially-indirect distribution, this can dynamically evolve into inter-layer exciton plus extra under external optical or electric field, making system flexible platform generate quasiparticles well mixtures. Notably, serve reservoir for both fillings of lattice, where resulting state from fermionic, fermionic-bosonic, nature controllably tuning fields. These results highlight hetero-trilayer semiconductors are informative toy-model simulate many-body correlations ranging Fermi-, Fermi-Bose-, Bose-Hubbard Hamiltonians.

Language: Английский

---

Tailoring Valley Polarization of Interlayer Excitons in van der Waals Heterostructure toward Optical Communication

Nano Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 14, 2025

Controlling the valley polarization of interlayer excitons in van der Waals heterostructures is essential for developing valleytronic devices. Here, we demonstrate manipulation a monolayer WSe2/WS2 heterostructure using dual-handedness metasurface. This metasurface, composed left- and right-handed gold nanoantenna arrays, exhibits distinct chiral optical responses. Introducing metasurface into significantly enhances degree exciton polarization, which quantitatively corresponds to circular dichroism (CD) excitons, via Purcell effects. A negative CD -16% yielded left-handed positive +25% harvested under σ+ excitation 532 nm at 77 K. Moreover, tunable with wavelength, reaching maximum 38% 620 σ- excitation, highest value from reported so far without applying external fields. Further, that this platform enables direct byte-invert arithmetic operations information transmission. capability highlights its potential error detection valleytronics-based communication systems.

Language: Английский

---