In terms of interlayer trions, electronic excitations in van der Waals heterostructures (vdWHs) can be classified into Type I (i.e., two identical charges in the same layer) and Type II (i.e., two identical charges in the different layers). Type I interlayer trions are investigated theoretically and experimentally. By contrast, Type II interlayer trions remain elusive in vdWHs, due to inadequate free charges, unsuitable band alignment, reduced Coulomb interactions, poor interface quality, etc. Here, the first observation of Type II interlayer trions is reported by exploring band alignments and choosing an atomically thin organic-inorganic system-monolayer WSe /bilayer pentacene heterostructure (1L + 2L HS). Both positive and negative Type II interlayer trions are electrically tuned and observed via PL spectroscopy. In particular, Type II interlayer trions exhibit in-plane anisotropic emission, possibly caused by their unique spatial structure and anisotropic charge interactions, which is highly correlated with the transition dipole moment of pentacene. The results pave the way to develop excitonic devices and all-optical circuits using atomically thin organic-inorganic bilayers.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/adma.202206212 | DOI Listing |
Two-dimensional metal-sulfur compounds have attracted much attention due to their novel physical properties, such as layered structure, ultrathin physical dimensions, and continuously tunable bandgap. The vertical stacking of different 2D semiconductors enables the heterojunction to retain the excellent properties of its constituent materials and has physical properties such as interlayer energy transfer and interlayer carrier transfer. In this paper, we utilize the carrier interlayer transfer properties of p-n heterojunctions and form heterojunctions using p-type Te and PdSe prepared with n-type monolayer WS using the microzone transfer technique.
View Article and Find Full Text PDFAdv Mater
November 2024
Strategic Technology Research Institute, Korea Research Institute of Standards and Science (KRISS), Daejeon, 34113, South Korea.
Monolayer (1L) group VI transition metal dichalcogenides (TMDs) exhibit broken inversion symmetry and strong spin-orbit coupling, offering promising applications in optoelectronics and valleytronics. Despite their direct bandgap, high absorption coefficient, and spin-valley locking in K or K' valleys, the ultra-short valley lifetime limits their room-temperature applications. In contrast, multilayer TMDs, with more absorptive layers, sacrifice the direct bandgap and valley polarization upon gaining inversion symmetry from the bilayer structure.
View Article and Find Full Text PDFPhys Rev Lett
August 2024
Technical University of Munich, TUM School of Natural Sciences, Physics Department, 85748 Garching, Germany.
Heterostructures of two-dimensional transition metal dichalcogenides are emerging as a promising platform for investigating exotic correlated states of matter. Here, we propose to engineer Bose-Fermi mixtures in these systems by coupling interlayer excitons to doped charges in a trilayer structure. Their interactions are determined by the interlayer trion, whose spin-selective nature allows excitons to mediate an attractive interaction between charge carriers of only one spin species.
View Article and Find Full Text PDFNat Commun
August 2024
Department of Physics, Philipps-Universität Marburg, Marburg, Germany.
Doped van der Waals heterostructures host layer-hybridized trions, i.e. charged excitons with layer-delocalized constituents holding promise for highly controllable optoelectronics.
View Article and Find Full Text PDFACS Appl Mater Interfaces
July 2024
Department of Physics, Indian Institute of Science Education and Research Bhopal, Bhopal 462066, India.
The semiconducting layered transition metal dichalcogenides (e.g., WS) are excellent candidates for the realization of optoelectronic and nanophotonic applications on account of their band gap tunability, high binding energy and oscillator strength of the excitons, strong light-matter interaction, appreciable charge carrier mobility, and valleytronic properties.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!