Long-Wave-Infrared Near-Field Microscopy

Keilmann, F.; Knoll, B.; Krämer, A.

doi:10.1002/(sici)1521-3951(199909)215:1<849::aid-pssb849>3.0.co;2-l

Cited by 21 publications

(6 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The interest in SFG microscopy is primarily due to the chemical information which becomes obtainable from molecules explicitly residing at interfaces via their vibrations . It is important to note that there is rapid ongoing progress in the development of linear-IR NSOM. − These linear-IR studies, however, suffer from high background signals, low contrast, problems with topographical artifacts, and have intrinsic bulk sensitivity. Also, progress in coupling Raman spectroscopy with NSOM has been made, − but this technique, which also inherently exhibits bulk sensitivity, does not yet lend itself to a broad range of samples.…”

Section: Sum Frequency Generation Nsommentioning

confidence: 99%

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

et al. 2002

View full text Add to dashboard Cite

The emerging field of coherent nonlinear near-field scanning optical microscopy (NSOM) is reviewed. Second harmonic, third harmonic, and sum frequency generation (SHG, THG, and SFG) are explored as means of providing chemically and environmentally selective probes with nanometer spatial resolution provided by scanning probe microscopy. Chemical selectivity is generated via resonant enhancement of the nonlinear signals, whereas interface vs bulk contrast is achieved by the order (even vs odd) of the optical process. A method of producing higher spectral resolution, and thus increased chemical selectivity, is also demonstrated in the form of near-field detected multiplex (or "broad-bandwidth") SFG (MSFG). Applications to biological and material samples are described.

show abstract

Section: Sum Frequency Generation Nsommentioning

confidence: 99%

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

et al. 2002

View full text Add to dashboard Cite

show abstract

“…From this point forward, the possibility of using microwave signals both to characterize the electrical behavior of materials on a micro-or nano-scale, and to measure the inherent electrical properties (complex permittivity and permeability) of materials in the microwave frequency regime, including tissues and other biological samples, were now widely appreciated. Since 2000, many new variations on the original SMM themes have been presented, including scattering systems that impose the microwave signals from free space onto the probes and sample [21], comb generating input signal systems [22], extremely broadband time domain spectroscopy instruments that take advantage of short pulsed lasers or traditional broadband Fourier transform techniques in the THz regime [23], plus dozens of variations of the AFM (atomic force microscopy) and STM (scanning tunneling microscopy) probe structures to incorporate voltage, current, magnetic field, force, temperature, spin-state and charge sensing [24].…”

Section: (Smm) Was Born!mentioning

confidence: 99%

Microwaves Are Everywhere: “SMM: Nano-Microwaves”

Siegel

2021

IEEE J. Microw.

View full text Add to dashboard Cite

If the Twentieth Century boasted of the Space Age and the Computer Age, the Twenty-First Century is certainly starting off with the Age of Biology, or at least Biochemistry. The enormous impact of CRISPR (clustered regularly interspaced short palindromic repeats), LAMP (loop-mediated isothermal amplification), cryo-EM (electron microscopy), and many other nano-techniques in the biosciences is transforming the world in so many ways, not the least of which are the diagnostic tests and vaccines that are helping our global pandemic. Microwaves are huge compared to the likes of optical wavelengths and, at least for the world of bio-spectroscopy, being able to perform and take advantage of standard microwave materials measurements at a cellular (micron) and even molecular (nanometer) scale has been a major impediment to applications for this well-developed electronics technology and instrumentation. In the early part of the 21 st Century, the fields of AFM (atomic force microscopy) and SMM (scanning microwave microscopy) came together and spun off a handful of commercial applications and instruments stimulated by some very clever engineering and bio researchers and partnerships. In this, our fourth tutorial article in our continuing series on the ubiquitous presence and applications of microwaves, we take a look at the origins, instruments, biological applications, and goals for "nano-microwaves" the use of microwaves at nanometer scales.INDEX TERMS Scanning microwave microscopy (SMM-VNA), THz near-field scattering microscopy (SMM-THz), near-field microwave imaging, near-field THz spectroscopy, nano-microwaves.This article has been accepted for inclusion in a future issue of this journal. Content is final as presented, with the exception of pagination.

show abstract

“…The local optical response of a sample can be determined with a lateral resolution essentially given by the effective apex radius. Images based on elastic scattering have been demonstrated at frequencies ranging from the visible to the microwave [3][4][5]. Inelastic spectroscopic phenomena such as Raman scattering and photoluminescence are also accessible [6,7].…”

Section: Introductionmentioning

confidence: 99%

Simulation of optical near and far fields of dielectric apertureless scanning probes

Esteban¹,

Vogelgesang²,

Kern³

2008

Nanotechnology

View full text Add to dashboard Cite

We study apertureless field enhancing optical probes beyond the spherical approximation in a smooth transition towards up to 3 µm long conical silicon tips. Such tips are used in apertureless scanning near field optical microscopy, which holds the promise of sub 10 nm lateral resolution. A fully three-dimensional numerical solution to the Maxwell equations is obtained with the multiple multipole method giving simultaneously both near fields and scattered far fields. The significance of focused beam excitation for work with long tips is illustrated and the relative influence of relevant length scales such as tip length, excitation wavelength, and beam waist radius is discussed. In the limit of vanishing tip apex radius, the near field grows without bounds, whereas the far field remains finite. We verify that for small apex radii the near field confinement at the tip apex, which is related to the achievable lateral resolution, scales with the inverse of the radius. We find, however, that long tips exhibit a markedly lower confinement than spherical or very short tips. Relevant for experimental studies, we demonstrate how scanning the excitation field with long conical tips can be a useful technique for mapping the focal volume. We show that the normalized near field at the tip apex is robustly tolerant against small misalignments or misorientations of illumination focus and tip apex.

show abstract

Long-Wave-Infrared Near-Field Microscopy

Cited by 21 publications

References 11 publications

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

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

Microwaves Are Everywhere: “SMM: Nano-Microwaves”

Simulation of optical near and far fields of dielectric apertureless scanning probes

Contact Info

Product

Resources

About