High-performance THz photodetection is unprecedentedly accessed by integrating a topological Dirac(Weyl)semimetal in a carefully designed antenna at deep-subwavelength scales.
Within the class of two-dimensional materials, transition metal dichalcogenides (TMDs), are extremely appealing for a variety of technological applications. Moreover, the manipulation of the layered morphology at the ...Within the class of two-dimensional materials, transition metal dichalcogenides (TMDs), are extremely appealing for a variety of technological applications. Moreover, the manipulation of the layered morphology at the nanoscale is a knob for further tailoring their physical and chemical properties towards target applications. Here, the combination of atomic layer deposition (ALD) and chemical vapour deposition (CVD) is presented as a general approach for the fabrication of TMD layers arranged in arbitrary geometry at the nanoscale. Indeed, following such all-chemical based approach, high-resolution electron microscopy shows the conformal growth of MoS2 to nano-trench pattern obtained in SiO2 substrates on large area. Growth is uniform not only in the flat region of the pattern but also at the hinges and throughout vertical faces, without rupture, all along the rectangular shape profile of the trenches. Furthermore, MoS2 bending dramatically affects the electron-phonon coupling as demonstrated by resonant Raman scattering. The proposed approach opens the door to the on-demand manipulation of the TMDs properties by large-scale substrate pattern design.展开更多
Two-dimensional materials are today a solid reality in condensed matter physics due to the disruptive discoveries about graphene.The class of the X-enes,namely,graphene-like single element artificial crystals,is quick...Two-dimensional materials are today a solid reality in condensed matter physics due to the disruptive discoveries about graphene.The class of the X-enes,namely,graphene-like single element artificial crystals,is quickly emerging driven by the high-momentum generated by silicene.Silicene,in addition to the graphene properties,shows up incidentally at the end of Moore’s law debate in the electronic era.Indeed,silicene occurs as the crafted shrunk version of silicon long yearned by device manufacturers to improve the performances of their chips.Despite the periodic table kinship with graphene,silicene and the X-enes must deal with the twofold problem of their metastable nature,i.e.,the stabilization on a substrate and out of vacuum environment.Synthesis on different substrates and deep characterization through electronic and optical techniques of silicene in the early days have been now following by the tentative steps towards reliable integration of silicene into devices.Here,we review three paradigmatic cases of silicene grown by molecular beam epitaxy showing three different possible applications,aiming at extending the exploitation of silicene out of the nanoelectronics field and thus keeping silicon a key player in nanotechnology,just in a thinner fashion.展开更多
文摘High-performance THz photodetection is unprecedentedly accessed by integrating a topological Dirac(Weyl)semimetal in a carefully designed antenna at deep-subwavelength scales.
文摘Within the class of two-dimensional materials, transition metal dichalcogenides (TMDs), are extremely appealing for a variety of technological applications. Moreover, the manipulation of the layered morphology at the nanoscale is a knob for further tailoring their physical and chemical properties towards target applications. Here, the combination of atomic layer deposition (ALD) and chemical vapour deposition (CVD) is presented as a general approach for the fabrication of TMD layers arranged in arbitrary geometry at the nanoscale. Indeed, following such all-chemical based approach, high-resolution electron microscopy shows the conformal growth of MoS2 to nano-trench pattern obtained in SiO2 substrates on large area. Growth is uniform not only in the flat region of the pattern but also at the hinges and throughout vertical faces, without rupture, all along the rectangular shape profile of the trenches. Furthermore, MoS2 bending dramatically affects the electron-phonon coupling as demonstrated by resonant Raman scattering. The proposed approach opens the door to the on-demand manipulation of the TMDs properties by large-scale substrate pattern design.
基金The authors acknowledge the funding support from H2020 European Research Council CoG 2017 Grant N.772261“XFab”Fondazione CARIPLO-Regione Lombardia for the project“CrystEL,”Grant N.2016-0978.
文摘Two-dimensional materials are today a solid reality in condensed matter physics due to the disruptive discoveries about graphene.The class of the X-enes,namely,graphene-like single element artificial crystals,is quickly emerging driven by the high-momentum generated by silicene.Silicene,in addition to the graphene properties,shows up incidentally at the end of Moore’s law debate in the electronic era.Indeed,silicene occurs as the crafted shrunk version of silicon long yearned by device manufacturers to improve the performances of their chips.Despite the periodic table kinship with graphene,silicene and the X-enes must deal with the twofold problem of their metastable nature,i.e.,the stabilization on a substrate and out of vacuum environment.Synthesis on different substrates and deep characterization through electronic and optical techniques of silicene in the early days have been now following by the tentative steps towards reliable integration of silicene into devices.Here,we review three paradigmatic cases of silicene grown by molecular beam epitaxy showing three different possible applications,aiming at extending the exploitation of silicene out of the nanoelectronics field and thus keeping silicon a key player in nanotechnology,just in a thinner fashion.
