Ab-initio Calculation of Nonlinear Optical Susceptibilities in Germanium Quantum Dots
Paper i proceeding, 2018

Using Time Independent Density Functional Theory (TIDFT) implemented in SIESTA (R) we calculated the 2nd order and 3rd order nonlinear optical susceptibilities of small Germanium Quantum Dots (GeQD). We observe that the symmetry breaking due to surface termination enhances chi((2)) up to 299.1 pm/V which promises a strong Second Harmonic Generation (SHG) in GeQDs. Diagonal components for chi((2)) tensor are 52.5, 11.2, 299.1 pm/V, for xxx, yyy and zzz, respectively. The 3rd order susceptibility, chi((3)), is within the range of (0.2-0.4) x 10(-18) m(2)/V-2 which is close to the reported experimental values of bulk Germanium. This study suggests possibilities of enhancing SHG in GeQDs through symmetry breaking via strain and surface termination/reconstruction as well as suitability of this fast and less-computationally intensive Density Functional Theory (DFT)-based method in predicting nonlinear optical susceptibilities of nano structures.

Germanium

SIESTA (R)

DFT

second order susceptibility

Quantum Dots

nonlinear optics

Författare

Shadli Islam

Texas A&M University at Kingsville

Harsh Shah

Texas A&M University at Kingsville

Daryoush Shiri

Chalmers, Fysik, Kondenserade materiens teori

Reza Nekovei

Texas A&M University at Kingsville

Amit Verma

Texas A&M University at Kingsville

2018 IEEE 13TH NANOTECHNOLOGY MATERIALS AND DEVICES CONFERENCE (NMDC)

2378-377X (ISSN)

113-116

Ämneskategorier

Annan fysik

Teoretisk kemi

Den kondenserade materiens fysik

DOI

10.1109/NMDC.2018.8605886

ISBN

9781538610169

Mer information

Senast uppdaterat

2019-08-20