2D materials and van der Waals heterostructures

Abstract

The physics of two-dimensional (2D) materials and heterostructures based on such crystals has been developing extremely fast. With these new materials, truly 2D physics has begun to appear (for instance, the absence of long-range order, 2D excitons, commensurate-incommensurate transition, etc.). Novel heterostructure devices--such as tunneling transistors, resonant tunneling diodes, and light-emitting diodes--are also starting to emerge. Composed from individual 2D crystals, such devices use the properties of those materials to create functionalities that are not accessible in other heterostructures. Here we review the properties of novel 2D crystals and examine how their properties are used in new heterostructure devices.

Low-Frequency Electronic Noise in Quasi-1D TaSe3 van der Waals Nanowires

“…The investigations of the two-dimensional layers and heterostructures revealed new physics and demonstrated promising applications [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. Starting with graphene [3][4][5], and spreading to a wide range of layered van der Waals materials [6][7][8][9][10], successful isolation of individual atomic layers from their respective bulk crystals by mechanical exfoliation led to the fast growing research activities in the 2D materials.…”

Transparent, conductive solution processed spincast 2D Ti2CTx (MXene) films

“…The desirable optical and electronic behavior resulting from reduced dimensionality is even further enriched by the opportunity for co-assembly of different 2D materialtypes to form novel heterojunctions [12]. The classes of 2D materials known to date include graphene, transition metal dichalcogenides, metal oxides and double-metal hydroxides and MXenes, among others [11].…”

Two-Dimensional MoS2-Graphene-Based Multilayer van der Waals Heterostructures: Enhanced Charge Transfer and Optical Absorption, and Electric-Field Tunable Dirac Point and Band Gap

“…In recent five years, strong interlayer coupling and its effects on novel physical phenomena and diverse potential applications of vdWs heterostructures built from 2D materials has become a hot topic in various disciplines 2,15,16,18,19,[24][25][26][27][28] . The multilayer vdW heterostructures can be experimentally prepared by using state-of-the-art atomically thin 2D materials synthesis techiques, such as, chemical vapour deposition (CVD) to directly grow through the vertical layer-by-layer growth mode 29,30 , and exfoliation techniques with roll-to-roll assembly 2 and co-segregation method 31 .…”

“…Vertically stacked two-dimensional (2D) heterostructures made by layer-by-layer (such as graphene (GR) and related 2D materials) in a precisely chosen sequence, has led to promising new materials for various fields, including nanoelectronics, energy conversion and storage, nanooptics, and catalysis [1][2][3] . These heterogeneous stacks have unusual properties that are not present in individual layers and encompass a wide spectrum of physical and chemical phenomena exemplified by new van Hove singularities [4][5][6][7] , Fermi velocity renormalization 8,9 , unconventional quantum Hall effects 10 , Hofstadter's butterfly pattern [11][12][13][14] , and others.…”

“…The multilayer vdW heterostructures can be experimentally prepared by using state-of-the-art atomically thin 2D materials synthesis techiques, such as, chemical vapour deposition (CVD) to directly grow through the vertical layer-by-layer growth mode 29,30 , and exfoliation techniques with roll-to-roll assembly 2 and co-segregation method 31 . Interlayer coupling in 2D heterostructures has proved to be van der Waals (vdW) interaction, which becomes a promising approach for modifying the materials properties of 2D heterostructures while maintaining many of the desired properties of pristine individual layers, such as GR's high charge carrier mobility 1,2 . Although vdW interactions in these 2D…”