Enhanced Optical Emission from 2D InSe Bent onto Si‐Pillars. Issue 18 (15th June 2020)

• Record Type: Journal Article
• Authors: Mazumder, Debarati; Xie, Jiahao; Kudrynskyi, Zakhar R.; Wang, Xinjiang; Makarovsky, Oleg; Bhuiyan, Mahabub A.; Kim, Hyunseok; Chang, Ting‐Yuan; Huffaker, Diana L.; Kovalyuk, Zakhar D.; Zhang, Lijun; Patanè, Amalia
• Is Part Of: Advanced optical materials. Volume 8:Issue 18(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-06-15
• Subjects: 2D excitons -- enhanced luminescence -- indium selenide -- Si pillars; Optical materials -- Periodicals; Photonics -- Periodicals; 620.11295
• DOI: 10.1002/adom.202000828
• Languages: English
• ISSNs: 2195-1071

Abstract

Abstract: Controlling the propagation and intensity of an optical signal is central to several technologies ranging from quantum communication to signal processing. These require a versatile class of functional materials with tailored electronic and optical properties, and compatibility with different platforms for electronics and optoelectronics. Here, the inherent optical anisotropy and mechanical flexibility of atomically thin semiconducting layers are investigated and exploited to induce a controlled enhancement of optical signals. This enhancement is achieved by straining and bending layers of the van der Waals crystal indium selenide (InSe) onto a periodic array of Si‐pillars. This enhancement has strong dependence on the layer thickness and is modelled by first‐principles electronic band structure theory, revealing the role of the symmetry of the atomic orbitals and light polarization dipole selection rules on the optical properties of the bent layers. The effects described in this paper are qualitatively different from those reported in other materials, such as transition metal dichalcogenides, and do not arise from a photonic cavity effect, as demonstrated before for other semiconductors. The findings on InSe offer a route to flexible nano‐photonics compatible with silicon electronics by exploiting the flexibility and anisotropic and wide spectral optical response of a 2D layered material. Abstract : An enhancement of photoluminescence and Raman signals is demonstrated in atomically thin InSe layers. This is achieved by straining and bending InSe onto a periodic array of Si nanopillars and exploiting the inherent optical anisotropy and mechanical flexibility of InSe. The measured effects depend on the InSe layer thickness and are explained by first‐principles band structure calculations.