Fabrication of nonlinear optical devices in ionically self-assembled monolayers

ABSTRACTIonically self-assembled monolayers (ISAMs) have recently been shown to spontaneously exhibit a polar ordering that gives rise to substantial second order nonlinear optical response. The deposition of ISAMs has been studied in situ via second harmonic generation. This is a particularly sensitive probe of the growth of nanometer-thick films since the centrosymmetry of the immersion solutions, the substrate, and the container yields no SHG contribution from these bulk components. Upon immersion in the NLO-active polyelectrolyte solution, the SHG rises sharply over the first minute. When a film is immersed into salt water, the SHG decreases significantly only to be restored when the salt solution is replaced with deionized water.

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Nonlinear Optical Microscopy for Imaging Patterned Self-Assembled Monolayers

MRS Proceedings ◽

10.1557/proc-440-209 ◽

1996 ◽

Vol 440 ◽

Author(s):

L. Smilowitz ◽

Q.X. Jia ◽

X. Yang ◽

D.Q. Li ◽

D. McBranch ◽

...

Keyword(s):

Nonlinear Optical ◽

Second Harmonic ◽

Self Assembled Monolayers ◽

Optical Technique ◽

Nonlinear Optical Microscopy ◽

Surface Sensitivity ◽

Surfaces And Interfaces ◽

Assembled Monolayers ◽

Potential Applications ◽

Self Assembled

AbstractWe have used the inherent surface sensitivity of second harmonic generation (SHG) to develop an instrument for nonlinear optical (NLO) microscopy of surfaces and interfaces. This optical technique is ideal for imaging nanometer thick self-assembled monolayers (SAM's) which have been patterned using photolithographic techniques. In this paper we demonstrate the application of SHG microscopy to patterned SAM's of the noncentrosymmetric molecule calixarene and discuss other potential applications for this new technique.

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Second-order nonlinear optical thin films fabricated from ionically self-assembled monolayers

Technical Digest. Summaries of Papers Presented at the International Quantum Electronics Conference. Conference Edition. 1998 Technical Digest Series, Vol.7 (IEEE Cat. No.98CH36236) ◽

10.1109/iqec.1998.680091 ◽

2002 ◽

Cited By ~ 1

Author(s):

J.R. Heflin ◽

C. Figura ◽

D. Marciu ◽

Y. Liu ◽

Y.X. Wang ◽

...

Keyword(s):

Thin Films ◽

Nonlinear Optical ◽

Second Order ◽

Self Assembled Monolayers ◽

Assembled Monolayers ◽

Self Assembled

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In Situ Second Harmonic Generation Measurements of the Growth of Nonlinear Optical Ionically Self-Assembled Monolayers

MRS Proceedings ◽

10.1557/proc-660-jj8.32 ◽

2000 ◽

Vol 660 ◽

Author(s):

C. Brands ◽

P.J. Neyman ◽

M.T. Guzy ◽

S. Shah ◽

K.E. Van Cott ◽

...

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

Nonlinear Optical ◽

Second Harmonic ◽

Self Assembled Monolayers ◽

Optical Polymer ◽

Wide Range ◽

Assembled Monolayers ◽

Self Assembled

ABSTRACTIonically self-assembled monolayers (ISAMs) have recently been shown to spontaneously exhibit a polar ordering that gives rise to a substantial second order nonlinear optical (NLO) response. Here, the deposition of ISAMs has been studied in situ via second harmonic generation (SHG). We show that the adsorption and ordering of a noncentrosymmetric nonlinear optical polymer is constant over a wide range of concentrations. Upon immersion in the NLO-active polyelectrolyte solution, the SHG rises sharply over the first minute. Immersion in the NLO-inactive partner polyelectrolyte leads to a reduction in the SHG signal. Furthermore, when the film is removed from the NLO-active solution and allowed to dry, the SHG increases rapidly as the water evaporates. These studies provide greater understanding of the processes by which noncentrosymmetric order is formed in ISAM films and allows design of improved self- assembled nonlinear optical materials.

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Control of Second-Order Nonlinear Optical Susceptibility in Ionically Self-Assembled Films by pH and Ionic Strength

MRS Proceedings ◽

10.1557/proc-598-bb4.9 ◽

1999 ◽

Vol 598 ◽

Author(s):

C. Figura ◽

P.J. Neyman ◽

D. Marciu ◽

C. Brands ◽

M.A. Murray ◽

...

Keyword(s):

Ionic Strength ◽

Nonlinear Optical ◽

Second Order ◽

Self Assembled Monolayers ◽

Nonlinear Optical Susceptibility ◽

Optical Susceptibility ◽

Nlo Response ◽

Assembled Monolayers ◽

Self Assembled ◽

The Relationship

ABSTRACTIonically self-assembled monolayers have been recently shown to spontaneously produce the noncentrosymmetric ordering that is required for a second order nonlinear optical (NLO) response. The precise thickness of each monolayer is determined by variables such as the pH and ionic strength of the immersion solutions. We show here that the relationship between polymer conformation and layer thickness dramatically affects the magnitude of the NLO response. The largest χ(2) values are found in the thinnest films, indicating that the NLO response is determined primarily by chromophores located at the layer interfaces, as opposed to those within the bulk of a layer.

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Vibrational sum-frequency generation study of molecular structure, sterical constraints and nonlinear optical switching contrast of mixed alkyl-azobenzene self-assembled monolayers

Zeitschrift für Physikalische Chemie ◽

10.1515/zpch-2020-1655 ◽

2020 ◽

Vol 234 (7-9) ◽

pp. 1427-1452 ◽

Cited By ~ 1

Author(s):

Saira Riaz ◽

Gernot Friedrichs

Keyword(s):

Molecular Structure ◽

Nonlinear Optical ◽

Sum Frequency Generation ◽

Self Assembled Monolayers ◽

Sum Frequency ◽

Nlo Response ◽

Assembled Monolayers ◽

Self Assembled ◽

Frequency Generation ◽

Insight Into

AbstractSelf-assembled monolayers (SAMs) of azobenzene (AB) functionalized alkyl thiols on gold diluted with simple alkyl thiols provide a straightforward way to photochromic surfaces with high and tunable photoswitching efficiency. Trans-cis isomerization of the AB molecule changes the physical properties of the surface, including the nonlinear optical (NLO) response. Vibrational sum-frequency generation (VSFG) spectroscopy as a nonlinear type of laser spectroscopy offers surface- and orientation-sensitive insight into the molecular structure of mixed SAMs. In this study, VSFG as well as ultraviolet-visible (UV/Vis) spectroscopy has been employed to investigate the morphology, molecular structure, and NLO response of mixed SAMs with systematically varied surface composition. Methylazobenzene (MeAB) has been used as the molecular switch with the methyl substituent serving as orientational VSFG marker. Both short-chain and long-chain alkyl thiol co-ligands have been used to gain insight into the interplay between SAM structure and sterical constraints that are known to limit the free switching volume. Underlining the dominating role of sterical effects for controlling photochromic properties, a strong inhibition of the photoswitching efficiency and NLO response has been observed for the SAMs with an alkyl thiol co-ligand long enough to spatially extend into the layer of the MeAB chromophore. Overall, with <12% signal change, the relative NLO switching contrasts remained low in all cases. VSFG spectral trends clearly revealed that the presumably higher photoswitching efficiency upon dilution with the co-ligand is counteracted by a loss of structural order of the chromophore.

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Nonlinear optical responses of self-assembled monolayers functionalized with indolino–oxazolidine photoswitches

Physical Chemistry Chemical Physics ◽

10.1039/c8cp02991a ◽

2018 ◽

Vol 20 (33) ◽

pp. 21590-21597 ◽

Cited By ~ 6

Author(s):

Claire Tonnelé ◽

Kornelia Pielak ◽

Jean Deviers ◽

Luca Muccioli ◽

Benoît Champagne ◽

...

Keyword(s):

Second Harmonic Generation ◽

Harmonic Generation ◽

Nonlinear Optical ◽

Second Harmonic ◽

Self Assembled Monolayers ◽

Optical Responses ◽

Assembled Monolayers ◽

Self Assembled

The second harmonic generation responses of photoresponsive self-assembled monolayers based on indolino–oxazolidine derivatives are computed using a sequential MD/DFT approach.

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