Nonlinear effects in photothermal-optical-beam-deflection imaging

Nonlinear phenomena have been observed during photothermal-optical-beam-deflection imaging experiments on samples of both high-purity aluminum and aluminum alloys. Evidence for nonlinear optical and thermal effects have been measured. Theoretical models have been developed as aids in understanding the different contrast mechanisms observed in linear and nonlinear photothermal images.

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Linear and Nonlinear Optical Properties of Molecules

Zeitschrift für Physikalische Chemie ◽

10.1524/zpch.1995.188.part_1_2.308a ◽

1995 ◽

Vol 188 (Part_1_2) ◽

pp. 308-309

Author(s):

R. Gade

Keyword(s):

Optical Properties ◽

Nonlinear Optical ◽

Nonlinear Optical Properties ◽

Linear And Nonlinear

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Linear and Nonlinear Optical Properties of Small Silicon Clusters

10.21236/ada225495 ◽

1990 ◽

Author(s):

Tapio T. Rantala ◽

Mark I. Stockman ◽

Daniel A. Jelski ◽

Thomas F. George

Keyword(s):

Optical Properties ◽

Nonlinear Optical ◽

Nonlinear Optical Properties ◽

Silicon Clusters ◽

Linear And Nonlinear

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Dispersive MHD waves and alfvenons in charge non-neutral plasmas

Nonlinear Processes in Geophysics ◽

10.5194/npg-15-681-2008 ◽

2008 ◽

Vol 15 (4) ◽

pp. 681-693 ◽

Cited By ~ 3

Author(s):

K. Stasiewicz ◽

J. Ekeberg

Keyword(s):

Soliton Solutions ◽

Theoretical Models ◽

Mhd Waves ◽

Space Plasmas ◽

Charge Effects ◽

Novel Technique ◽

Solitary Structures ◽

Spatial Dimensions ◽

Electric Potentials ◽

Linear And Nonlinear

Abstract. Dispersive properties of linear and nonlinear MHD waves, including shear, kinetic, electron inertial Alfvén, and slow and fast magnetosonic waves are analyzed using both analytical expansions and a novel technique of dispersion diagrams. The analysis is extended to explicitly include space charge effects in non-neutral plasmas. Nonlinear soliton solutions, here called alfvenons, are found to represent either convergent or divergent electric field structures with electric potentials and spatial dimensions similar to those observed by satellites in auroral regions. Similar solitary structures are postulated to be created in the solar corona, where fast alfvenons can provide acceleration of electrons to hundreds of keV during flares. Slow alfvenons driven by chromospheric convection produce positive potentials that can account for the acceleration of solar wind ions to 300–800 km/s. New results are discussed in the context of observations and other theoretical models for nonlinear Alfvén waves in space plasmas.

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Linear and nonlinear optical responses in the chiral multifold semimetal RhSi

npj Quantum Materials ◽

10.1038/s41535-020-00298-y ◽

2020 ◽

Vol 5 (1) ◽

Cited By ~ 1

Author(s):

Zhuoliang Ni ◽

B. Xu ◽

M.-Á. Sánchez-Martínez ◽

Y. Zhang ◽

K. Manna ◽

...

Keyword(s):

Nonlinear Optical ◽

Chemical Potential ◽

Technological Development ◽

Optical Responses ◽

Chiral Magnetic Effect ◽

Hole Band ◽

Linear And Nonlinear ◽

Characteristic Features ◽

Topological Semimetals ◽

Terahertz Emission Spectroscopy

AbstractChiral topological semimetals are materials that break both inversion and mirror symmetries. They host interesting phenomena such as the quantized circular photogalvanic effect (CPGE) and the chiral magnetic effect. In this work, we report a comprehensive theoretical and experimental analysis of the linear and nonlinear optical responses of the chiral topological semimetal RhSi, which is known to host multifold fermions. We show that the characteristic features of the optical conductivity, which display two distinct quasi-linear regimes above and below 0.4 eV, can be linked to excitations of different kinds of multifold fermions. The characteristic features of the CPGE, which displays a sign change at 0.4 eV and a large non-quantized response peak of around 160 μA/V2 at 0.7 eV, are explained by assuming that the chemical potential crosses a flat hole band at the Brillouin zone center. Our theory predicts that, in order to observe a quantized CPGE in RhSi, it is necessary to increase the chemical potential as well as the quasiparticle lifetime. More broadly, our methodology, especially the development of the broadband terahertz emission spectroscopy, could be widely applied to study photogalvanic effects in noncentrosymmetric materials and in topological insulators in a contact-less way and accelerate the technological development of efficient infrared detectors based on topological semimetals.

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