Nonlinear Chemical Imaging Nanomicroscopy:  From Second and Third Harmonic Generation to Multiplex (Broad-Bandwidth) Sum Frequency Generation Near-Field Scanning Optical Microscopy

Schaller, Richard D.; Johnson, Justin C.; Wilson, Kevin R.; Lee, Lynn F.; Haber, Louis H.; Saykally, Richard J.

doi:10.1021/jp0144653

Cited by 76 publications

(56 citation statements)

References 136 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…and photonic applications (metamaterials, LC-based tunable lasers, etc.). The integrated system also has immense potential in molecular and cellular biology [58][59][60][61][62][63][64], e.g., in determining the mechanism behind how lipid membranes organize into complex-shaped organelles [58,59], in tracking cellular processes such as metabolism [60], reconstructing cell lineage [62] by imaging different components of the cell in different nonlinear modalities, and transcending the diffraction limit in near-field scanning nonlinear optical microscopy [64]. Loops of cholesteric finger CF1 are optically generated with the HOT setup and are imaged in their lateral and vertical cross-sectional planes, in 3PEF (a, d) and CARS (c, e) imaging modes.…”

Section: Resultsmentioning

confidence: 99%

Three dimensional optical manipulation and structural imaging of soft materials by use of laser tweezers and multimodal nonlinear microscopy

Trivedi¹,

Lee²,

Bertness³

et al. 2010

Opt. Express

121

View full text Add to dashboard Cite

Abstract:We develop an integrated system of holographic optical trapping and multimodal nonlinear microscopy and perform simultaneous three-dimensional optical manipulation and non-invasive structural imaging of composite soft-matter systems. We combine different nonlinear microscopy techniques such as coherent anti-Stokes Raman scattering, multi-photon excitation fluorescence and multi-harmonic generation, and use them for visualization of long-range molecular order in soft materials by means of their polarized excitation and detection. The combined system enables us to accomplish both, manipulation in composite soft materials such as colloidal inclusions in liquid crystals as well as imaging of each separate constituents of the composite material in different nonlinear optical modalities. We also demonstrate optical generation and control of topological defects and simultaneous reconstruction of their three-dimensional long-range molecular orientational patterns from the nonlinear optical images.

show abstract

Section: Resultsmentioning

confidence: 99%

Three dimensional optical manipulation and structural imaging of soft materials by use of laser tweezers and multimodal nonlinear microscopy

Trivedi¹,

Lee²,

Bertness³

et al. 2010

Opt. Express

121

View full text Add to dashboard Cite

show abstract

“…38,45 Chemically etched SiO 2 nonmetal-coated fiber optic probes were produced with a ∼75 nm diameter tip and were mounted so as to overhang the end of the tuning fork by about 0.6 mm as described by Lee et al 46 Stable near-field feedback is facilitated with this overhanging probe design because in the solvatochromic measurements the tuning fork does not contact the liquid: only the fiber optic probe is immersed, which helps to maintain the high Q-factor that is essential for noncontact scanning. To prevent photooxidation of the sample, the entire NSOM system was sealed in a dry nitrogen purge box.…”

Section: Methodsmentioning

confidence: 99%

The Nature of Interchain Excitations in Conjugated Polymers: Spatially-Varying Interfacial Solvatochromism of Annealed MEH-PPV Films Studied by Near-Field Scanning Optical Microscopy (NSOM)

Schaller¹,

Lee²,

Johnson³

et al. 2002

J. Phys. Chem. B

Self Cite

View full text Add to dashboard Cite

The nature of interchain electronic species in conjugated polymers has been the subject of much debate. In this paper, we exploit a novel near-field scanning optical microscopy (NSOM)-based solvatochromism method to spatially image the difference in dipole moment, and hence the difference in degree of charge separation, between the ground and electronic excited states of the emissive interchain species in films of poly(2-methoxy-5-(2′-ethylhexyloxy)-1,4-phenylene vinylene) (MEH-PPV). The method uses NSOM to collect emission from near the surface of solid samples that are placed into contact with liquids of varying polarity. The solvatochromic spectral shifts of the interfacial luminescence are measured as a function of solvent polarity; the results are analyzed with an interfacial dielectric continuum model to determine the dipole moment of emissive excited states. Experiments performed on films of the laser dye trans-4-dicyanomethylene-2-methyl-6-p-dimethylaminostyryl-4H-pyran (DCM) in poly(methyl methacrylate) (PMMA) demonstrate that our interfacial NSOM solvatochromic method and analysis can successfully reproduce the known dipole change of DCM upon photoexcitation. With the method calibrated, we then apply it to the interchain luminescence from the surface of thermally annealed MEH-PPV films. The interfacial solvatochromic analysis reveals that the dominant interchain species in annealed MEH-PPV films is "excimer-like", exhibiting an ∼4-7 D decrease in dipole moment upon optical excitation. In a few highly localized regions of the film (ca. 1-2 µm in diameter), however, the interchain excited state exhibits a large (∼9-13 D) increase in dipole moment upon excitation, indicative of minority interchain species with a large degree of charge separation, such as exciplexes or polaron pairs. The large variation in excited-state dipole moments observed throughout the film is suggestive of an entire family of interchain species, each characterized by a different degree of charge separation. The fact that the large-dipole interchain species are found in spatially segregated domains implies that interchain charge separation in conjugated polymer films is associated with the presence of defects. When the molecular weight of the polymer is lowered, the large excited-state dipole regions increase in spatial extent, suggesting that the defects that promote charge separation are intrinsic and may be associated with the chain ends.

show abstract

“…They can be more effective than point scanning at retrieving high-resolution information (17,19). Nonlinear fluorescence is the basis for multiphoton fluorescence microscopy (20), and several other classical optical nonlinearities (21) have also found use in both far-field (22, 23) and near-field (24) microscopy.…”

mentioning

confidence: 99%

Nonlinear structured-illumination microscopy: Wide-field fluorescence imaging with theoretically unlimited resolution

Gustafsson

2005

Proc. Natl. Acad. Sci. U.S.A.

1,965

1,385

View full text Add to dashboard Cite

Contrary to the well known diffraction limit, the fluorescence microscope is in principle capable of unlimited resolution. The necessary elements are spatially structured illumination light and a nonlinear dependence of the fluorescence emission rate on the illumination intensity. As an example of this concept, this article experimentally demonstrates saturated structured-illumination microscopy, a recently proposed method in which the nonlinearity arises from saturation of the excited state. This method can be used in a simple, wide-field (nonscanning) microscope, uses only a single, inexpensive laser, and requires no unusual photophysical properties of the fluorophore. The practical resolving power is determined by the signal-to-noise ratio, which in turn is limited by photobleaching. Experimental results show that a 2D point resolution of <50 nm is possible on sufficiently bright and photostable samples.super resolution ͉ moiré ͉ resolution extension ͉ saturation T he fluorescence microscope has become a ubiquitous imaging tool in cell biology through its unique ability to image the 3D interior of a living specimen with multicolor molecular labels of extreme specificity, a combination of strengths not shared by higher-resolution techniques such as electron microscopy and scanned-probe methods. It is therefore unfortunate that its spatial resolution is subject to a hard limit caused by diffraction.Recently, ways have been found to bypass the diffraction limit. 2D resolution in the 30-nm range has been realized by using stimulated emission depletion (STED) (1). STED is based on saturated stimulated emission using two synchronized ultrafast laser sources (2, 3); the underlying concept has been generalized to encompass a class of reversible saturable phenomena (4). STED and other proposed methods (5-7) were conceived in the context of laser-scanning microscopy and are designed to directly minimize the size of a scanned focal point. This article demonstrates an alternative approach that brings theoretically unlimited resolution to a wide-field (nonscanning) microscope by using a nonlinear fluorescence response together with a periodic illumination pattern that fills the field of view.Both structured illumination light and optical nonlinearity, of course, are established ideas. Patterned light, for example, has been used for measuring surface shapes (8) and deformations (9) and for enhancing the sensitivity of fluorescence-recovery-afterphotobleaching experiments (10). Axially structured light has been used to enhance axial resolution in standing-wave fluorescence microscopy (11), 4Pi microscopy (12), and I 5 M (13). Lukosz and Marchand (14) suggested in 1963 that lateral light patterns could be used to enhance resolution, and such patterns have been used for both axial (15) and lateral (16-19) resolution enhancement. They can be more effective than point scanning at retrieving high-resolution information (17,19). Nonlinear fluorescence is the basis for multiphoton fluorescence microscopy (20), and several other c...

show abstract

Nonlinear Chemical Imaging Nanomicroscopy: From Second and Third Harmonic Generation to Multiplex (Broad-Bandwidth) Sum Frequency Generation Near-Field Scanning Optical Microscopy

Cited by 76 publications

References 136 publications

Three dimensional optical manipulation and structural imaging of soft materials by use of laser tweezers and multimodal nonlinear microscopy

Three dimensional optical manipulation and structural imaging of soft materials by use of laser tweezers and multimodal nonlinear microscopy

The Nature of Interchain Excitations in Conjugated Polymers: Spatially-Varying Interfacial Solvatochromism of Annealed MEH-PPV Films Studied by Near-Field Scanning Optical Microscopy (NSOM)

Nonlinear structured-illumination microscopy: Wide-field fluorescence imaging with theoretically unlimited resolution

Contact Info

Product

Resources

About