Design and optimization of the plasmonic graphene/InP thin-film solar-cell structure

Abstract

In this paper, a graphene/InP thin-film Schottky-junction solar cell with a periodic array of plasmonic back-reflector is proposed. In this structure, a single-layer graphene sheet is deposited on the surface of the InP to form a Schottky junction. Then, the layer stack of the proposed solar-cell is optimized to have a maximum optical absorption of 〈A W 〉 = 0.985 (98.5%) and short-circuit current density of J sc = 33.01 mA cm −2 .

Nano-Architecture Driven Plasmonic Field Enhancement in 3D Graphene Structures

“…The extreme light confinement by two-dimensional (2D) graphene plasmons enhances the electric field around the graphene surface, making the near-field intensity several orders of magnitude higher than the incident wave. The long lifetime tunable plasmon resonance alongside superior mechanical properties in graphene have been utilized for a diverse range of applications such as reconfigurable metamaterials and optoelectronic devices for photodetection, vibrational spectroscopy techniques, solar cells, cell therapeutics, and light sources. − However, the exponential decay of the enhanced field a few nanometers from the surface severely degrades the performances of graphene-based devices such as lower propagation length in graphene waveguides and interconnects, − diffusion-limited sensitivity of molecular sensors, − and low efficiency and long response time of photodetectors. − Attempts have been made to achieve stronger field enhancements with minimal spatial decay through arrays and stacks of graphene , including circular and triangular shaped ribbons − for large area hotspots of intensified electric (E) field. , Although, the 2D stacks and arrays exhibit highly tunable plasmon resonance through changes in ribbon width or Fermi levels, they can only produce nonhomogeneous hotspots localized to edges or a point and cannot significantly change the exponential decay in the field away from ribbon surface. For sensing applications, the presence of molecules results in a shift in the plasmon resonance and additional absorption peaks proportional to the molecules’ optical properties .…”