@article{85ebfd6470114815924b9db2cd5baa7b,
title = "Superlattice nonlinearities for Gigahertz-Terahertz generation in harmonic multipliers",
abstract = "Semiconductor superlattices are strongly nonlinear media offering several technological challenges associated with the generation of high-frequency Gigahertz radiation and very effective frequency multiplication up to several Terahertzs. However, charge accumulation, traps and interface defects lead to pronounced asymmetries in the nonlinear current flow, from which high harmonic generation stems. This problem requires a full nonperturbative solution of asymmetric current flow under irradiation, which we deliver in this paper within the Boltzmann-Bloch approach. We investigate the nonlinear output on both frequency and time domains and demonstrate a significant enhancement of even harmonics by tuning the interface quality. Moreover, we find that increasing arbitrarily the input power is not a solution for high nonlinear output, in contrast with materials described by conventional susceptibilities. There is a complex combination of asymmetry and power values leading to maximum high harmonic generation.",
keywords = "Asymmetric current flow, High harmonic generation, Interfaces, Semiconductor superlattices",
author = "Apostolos Apostolakis and Pereira, {Mauro F.}",
note = "Funding Information: The authors acknowledge access to computing and storage facilities owned by parties and projects contributing to the National Grid Infrastructure MetaCentrum provided under the programme “Projects of Large Research, Development, and Innovations Infrastructures” (CESNET LM2015042) is greatly appreciated. The authors acknowledge support by the Czech Science Foundation (GA{\v C}R) through grant No. 19-03765, the EU H2020-Europe's resilience to crises and disasters program (No. 832876, aqua3S) and Khalifa University of Science and Technology under Award No. CPRA-2020-Breathan. Funding Information: Research funding: The authors acknowledge support by the Czech Science Foundation (GA{\v C}R) through grant No. 19-03765, the EU H2020-Europe{\textquoteright}s resilience to crises and disasters program (H2020-grant agreement no. 832876, No. 832876, AQUA3S) and Khalifa University of Science and Technology under Award No. CPRA-2020-Breathan. Publisher Copyright: {\textcopyright} 2020 Apostolos Apostolakis and Mauro F. Pereira, published by De Gruyter. Attribution 4.0 International License. This work is licensed under the Creative Commons",
year = "2020",
month = sep,
day = "1",
doi = "10.1515/nanoph-2020-0155",
language = "British English",
volume = "9",
pages = "3941--3952",
journal = "Nanophotonics",
issn = "2192-8614",
publisher = "Walter de Gruyter",
number = "12",
}