Interlayer Excitons in Transition Metal Dichalcogenide Semiconductors for 2D Optoelectronics

Abstract

HfS 2 780 [71] WS 2 /HfS 2 350-200 [8]

Structure modulation of two-dimensional transition metal chalcogenides: recent advances in methodology, mechanism and applications

“…To date, there are reviews on the synthesis, phase transition, properties and applications of TMDs and investigations on some of their defects. [12][13][14][15][16][17][18] Nevertheless, as a series of important model materials, defects and derivatives of TMDs, denoted as modulated structures herein, should be classified into several types based on their atomic arrangements, and thus studies and conclusions can be sorted and drawn systematically to report their inherent structure-activity relationships. Together with the expansion of TMDs and corresponding modulated structures, the relation among their atomic arrangements, electron structures and properties is gradually becoming necessary to establish to determine the root cause of these structures and corresponding regulated properties.…”

Versatile van der Waals heterostructures of γ-GeSe with h-BN/graphene/MoS2

“…The successful exfoliation of graphene initiated a new era of two-dimensional (2D) materials. 1 A large family of 2D materials, including transition metal dichalcogenides (TMDs), 2,3 phosphorene, 4,5 hexagonal boron nitride (h-BN), 6,7 and MXenes, 8,9 have attracted extensive attention owing to their distinct mechanical, electronic, and optical properties. A single type of 2D material generally cannot meet the requirements of practical applications, but the construction of van der Waals heterostructures (vdWHs) by integrating different types of 2D layers together renders additional functionality and promotes performance.…”

Nanocavity-induced trion emission from atomically thin WSe2

“…These strong Coulombic interactions and reduced dielectric screening effect give rise to free excitons and charged excitons (trions) 7 – 9 . Due to the high (> 100 meV) exciton binding energy 10 , the free excitons remain stable and display strong exciton resonance even at room temperature, and thus determine the optical response and light emission properties of TMDCs. However, the trion is not easily observed as its binding energy is much smaller than the free excitons 11 , 12 .…”