Related papers: Electrical control of interlayer exciton dynamics …
We studied the exciton properties in double layers of transition metal dichalcogenides (TMDs) with a dielectric spacer between the layers. We developed a method based on an expansion of Chebyshev polynomials to solve the Wannier equation…
Monolayer semiconductors, given their thickness at the atomic scale, present unique electrostatic environments due to the sharp interfaces between the semiconductor film and surrounding materials. These interfaces significantly impact both…
Identifying two-dimensional heterostructures with exceptional electronic and optical properties remains an active area of research in advanced optoelectronics. Here, we present a comprehensive first-principles investigation of the…
Since the seminal work on MoS2 monolayers, photoexcitation in atomically-thin transition metal dichalcogenides (TMDCs) has been assumed to result in excitons with large binding energies (~ 200-600 meV). Because the exciton binding energies…
Atomistic van der Waals heterostacks are ideal systems for high-temperature exciton condensation because of large exciton binding energies and long lifetimes. Charge transport and electron energy-loss spectroscopy showed first evidence of…
Bilayer van der Waals (vdW) heterostructures such as MoS2/WS2 and MoSe2/WSe2 have attracted much attention recently, particularly because of their type II band alignments and the formation of interlayer exciton as the lowest-energy…
The emergence of semiconducting materials with inert or dangling bond-free surfaces has created opportunities to form van der Waals heterostructures without the constraints of traditional epitaxial growth. For example, layered…
Coupled two-dimensional electron-hole bilayers provide a unique platform to study strongly correlated Bose-Fermi mixtures in condensed matter. Electrons and holes in spatially separated layers can bind to form interlayer excitons, composite…
We investigate the excitonic species in WS$_{2}$ monolayers transferred onto III-V semiconductor substrates with different surface treatments. When the III-V substrates were covered with amorphous native oxides, negatively charged excitons…
Excitons are fundamental excitations that govern the optical properties of semiconductors. Interacting excitons can lead to various emergent phases of matter and large nonlinear optical responses. In most semiconductors, excitons interact…
Many of the fundamental optical and electronic properties of atomically thin transition metal dichalcogenides are dominated by strong Coulomb interactions between electrons and holes, forming tightly bound atom-like excitons. Here, we…
Vertical heterostructures (HS) of transition metal dichalcogenides (TMDs) host interlayer excitons (ILX), with electrons and holes residing in different layers. With respect to their intralayer counterparts, ILX feature much longer…
Lateral heterostructures built of monolayers of transition metal dichalcogenides (TMDs) are characterized by a thin 1D interface exhibiting a large energy offset. Recently, the formation of spatially separated charge-transfer (CT) excitons…
Long lifetimes of spatially indirect excitons (IXs), also known as interlayer excitons, allow implementing both quantum exciton systems and long-range exciton transport. Van der Waals heterostructures (HS) composed of atomically thin layers…
Excitons are the neutral quasiparticles that form when Coulomb interactions create bound states between electrons and holes. Due to their bosonic nature, excitons are expected to condense and exhibit superfluidity at sufficiently low…
Excitons -- quasiparticles formed by the binding of an electron and a hole through electrostatic attraction -- hold promise in the fields of quantum light confinement and optoelectronic sensing. Atomically thin transition metal…
Excitonic states of tightly-bound electron-hole pairs dominate the optical response in a growing class of two-dimensional (2D) materials and their van der Waals (vdW) heterostructures. In transition metal dichalcogenides (TMDs) a useful…
Control over the optical properties of atomically thin two-dimensional (2D) layers, including those of transition metal dichalcogenides (TMDs), is needed for future optoelectronic applications. Remarkable advances have been achieved through…
In order to fully exploit the potential of transition metal dichalcogenide monolayers (TMD-MLs), the well-controlled creation of atomically sharp lateral heterojunctions within these materials is highly desirable. A promising approach to…
We reveal stacking-induced strong coupling between atomic motion and interlayer excitons through photocurrent measurements of WSe$_2$/MoSe$_2$ heterojunction photodiodes. Strong coupling manifests as pronounced periodic sidebands in the…