First-principles study of crystal structure, electronic structure, and second-harmonic generation in a polar double perovskite Bi2ZnTiO6

ABSTRACTWe present our implementation of the length-gauge formalism of Sipe and coworkers (Phys. Rev. B 48, 11705 (1993); ibid 52, 14636 (1995)) using the linearized muffin-tin orbital (LMTO) method and discuss its application to the calculation of second order response functions. The importance of gap corrections beyond LDA is discussed. As primary application, we discuss the second harmonic generation (SHG) coefficients of the SiC polytypes and of the chalcopyrites of both the II-IV-V2 and I-III-VI2 families. These examples illustrate the relation of the second order response function to the modification of the crystal structure and chemical substitutions.

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Anomalously Strong Second‐Harmonic Generation in GaAs Nanowires via Crystal‐Structure Engineering

Advanced Functional Materials ◽

10.1002/adfm.202104671 ◽

2021 ◽

pp. 2104671

Author(s):

Bin Zhang ◽

Jan E. Stehr ◽

Ping‐Ping Chen ◽

Xingjun Wang ◽

Fumitaro Ishikawa ◽

...

Keyword(s):

Crystal Structure ◽

Second Harmonic Generation ◽

Harmonic Generation ◽

Second Harmonic ◽

Gaas Nanowires ◽

Structure Engineering

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Table-top extreme ultraviolet second harmonic generation

Science Advances ◽

10.1126/sciadv.abe2265 ◽

2021 ◽

Vol 7 (21) ◽

pp. eabe2265

Author(s):

Tobias Helk ◽

Emma Berger ◽

Sasawat Jamnuch ◽

Lars Hoffmann ◽

Adeline Kabacinski ◽

...

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

First Principles ◽

Extreme Ultraviolet ◽

Second Harmonic ◽

High Harmonic ◽

Electronic Structure Calculations ◽

Free Electron Lasers ◽

X Ray ◽

Structure Calculations

The lack of available table-top extreme ultraviolet (XUV) sources with high enough fluxes and coherence properties has limited the availability of nonlinear XUV and x-ray spectroscopies to free-electron lasers (FELs). Here, we demonstrate second harmonic generation (SHG) on a table-top XUV source by observing SHG near the Ti M2,3 edge with a high-harmonic seeded soft x-ray laser. Furthermore, this experiment represents the first SHG experiment in the XUV. First-principles electronic structure calculations suggest the surface specificity and separate the observed signal into its resonant and nonresonant contributions. The realization of XUV-SHG on a table-top source opens up more accessible opportunities for the study of element-specific dynamics in multicomponent systems where surface, interfacial, and bulk-phase asymmetries play a driving role.

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Strong second harmonic generation in SiC, ZnO, GaN two-dimensional hexagonal crystals from first-principles many-body calculations

Physical Chemistry Chemical Physics ◽

10.1039/c5cp00601e ◽

2015 ◽

Vol 17 (14) ◽

pp. 9533-9540 ◽

Cited By ~ 26

Author(s):

C. Attaccalite ◽

A. Nguer ◽

E. Cannuccia ◽

M. Grüning

Keyword(s):

Second Harmonic Generation ◽

Real Time ◽

Harmonic Generation ◽

First Principles ◽

Function Theory ◽

Second Harmonic ◽

Two Dimensional ◽

Many Body ◽

Ti:Sapphire Laser ◽

Hexagonal Crystals

By using a real-time approach based on Green's function theory we predict a strong second-harmonic generation (SHG) for frequencies at which Ti:sapphire laser operates and for which the materials are transparent.

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