Nonlinear Optical Susceptibilities of [100], [110] and [111] Silicon Nanowires: A DFT Study
Paper i proceeding, 2024

Using time-independent density functional theory (TIDFT), we demonstrate enhancement of the 2nd order optical susceptibilities of narrow (1 nm – 2 nm) unstrained Silicon Nanowires (SiNW) due to surface termination. It is shown that x(2) is enhanced up to 200 pm/V which promises a strong second harmonic generation (SHG) in SiNWs. For [100, 110] and [111] SiNWs, the yxx component of x(2) tensor is 81, 225 and 81 pm/V, respectively. These are in close agreement with values reported for strained silicon waveguides in experiments. For [110] and [100] nanowires, the 3rd order nonlinear optical susceptibility, x(3) , is within the range of (0.1−12)×10−18 m 2 /V 2 which is close to the experimental values for bulk silicon. For [111] nanowires this is 100 times better than bulk silicon. This study shows methods of enhancing SHG in SiNWs through symmetry breaking via strain and/or surface termination and reconstruction. It also showcases the suitability of this fast DFT-based method in predicting the nonlinear optical susceptibilities of nano structures.

nonlinear optical susceptibility,

DFT, silicon nanowire, band structure, photon

Författare

Daryoush Shiri

Chalmers, Mikroteknologi och nanovetenskap, Kvantteknologi

M. Golam Rabbani

Intel Corporation

Proceedings of the IEEE Conference on Nanotechnology

19449399 (ISSN) 19449380 (eISSN)

36-40
979-8-3503-8624-0 (ISBN)

24th IEEE International Conference on Nanotechnology, NANO 2024
Gijon, Spain,

Drivkrafter

Hållbar utveckling

Styrkeområden

Nanovetenskap och nanoteknik

Materialvetenskap

Infrastruktur

C3SE (Chalmers Centre for Computational Science and Engineering)

Nanotekniklaboratoriet

Ämneskategorier

Atom- och molekylfysik och optik

Nanoteknik

Den kondenserade materiens fysik

DOI

10.1109/NANO61778.2024.10628839

Mer information

Senast uppdaterat

2024-09-18