Studies of the Kerr Effect in High Resolution Spectroscopy

1971 ◽  
Vol 49 (7) ◽  
pp. 914-931 ◽  
Author(s):  
J. M. Brown ◽  
A. D. Buckingham ◽  
D. A. Ramsay
Keyword(s):  
High Resolution ◽  
Kerr Effect ◽  
High Resolution Spectroscopy ◽  
Quarter Wave Plate ◽  
Order Effects ◽  
Absorption Bands ◽  
Stark Effects ◽  
Quarter Wave ◽  
Symmetric Top Molecules ◽  
Kerr Constants

The general theory of the Kerr effect in the region of absorption bands is described. Expressions are derived for the Kerr constants B[=(nz − nx)ω/2πcFz2] and B′[=(kz − kx)ω/2πcFz2] for symmetric top molecules at frequencies close to transitions involving levels with K ≠ 0. The application of the theory to asymmetric top molecules and the inclusion of second-order effects are discussed.Kerr spectra of the 3390 Å band of formaldehyde and of the 3821 Å band of propynal have been photographed under high resolution. The most prominent lines in these spectra are those which show predominantly first-order Stark effects. Photoelectric methods are described involving (a) a rotating quarter-wave plate and (b) a rotating polarizer; they permit the recording of the pure birefringence (B) and pure dichroism (B′) respectively.

scholarly journals High Resolution Spectroscopy With Molecular Beams and Tunable Lasers

1998 ◽  
Vol 18 (1-2) ◽  
pp. 1-11 ◽  
Author(s):  
R. Vetter ◽  
P. Luc ◽  
C. Amiot
Keyword(s):  
Electronic Structure ◽  
High Resolution ◽  
Diatomic Molecules ◽  
Reaction Dynamics ◽  
Molecular Beams ◽  
Tunable Lasers ◽  
High Resolution Spectroscopy ◽  
Absorption Bands ◽  
Quantum Numbers ◽  
Laser Techniques

High resolution Doppler-free laser techniques are used in beam experiments to improve the spectroscopic description of complex diatomic molecules. The case of TiO is considered here for its implication in reaction dynamics studies and its interest in Astrophysics. Two absorption bands in the visible have been analyzed: B3Π−X3 Δ(1−0) and c1Φ−a1 Δ(0−0). Owing to accurate wavenumber measurements, it has been possible to extend the analysis to high rotational quantum numbers and to carry out detailed spectroscopic calculations. They show that a careful revisiting of the TiO electronic structure is necessary.

Microcalorimeters for X-Ray Spectroscopy

1988 ◽  
Vol 102 ◽  
pp. 41
Author(s):  
E. Silver ◽  
C. Hailey ◽  
S. Labov ◽  
N. Madden ◽  
D. Landis ◽  
...  
Keyword(s):  
High Resolution ◽  
High Efficiency ◽  
Thermal Response ◽  
Low Noise ◽  
High Resolution Spectroscopy ◽  
Superconducting Transition ◽  
Sapphire Substrates ◽  
Laboratory Plasmas ◽  
Adiabatic Demagnetization ◽  
Theoretical Predictions

The merits of microcalorimetry below 1°K for high resolution spectroscopy has become widely recognized on theoretical grounds. By combining the high efficiency, broadband spectral sensitivity of traditional photoelectric detectors with the high resolution capabilities characteristic of dispersive spectrometers, the microcalorimeter could potentially revolutionize spectroscopic measurements of astrophysical and laboratory plasmas. In actuality, however, the performance of prototype instruments has fallen short of theoretical predictions and practical detectors are still unavailable for use as laboratory and space-based instruments. These issues are currently being addressed by the new collaborative initiative between LLNL, LBL, U.C.I., U.C.B., and U.C.D.. Microcalorimeters of various types are being developed and tested at temperatures of 1.4, 0.3, and 0.1°K. These include monolithic devices made from NTD Germanium and composite configurations using sapphire substrates with temperature sensors fabricated from NTD Germanium, evaporative films of Germanium-Gold alloy, or material with superconducting transition edges. A new approache to low noise pulse counting electronics has been developed that allows the ultimate speed of the device to be determined solely by the detector thermal response and geometry. Our laboratory studies of the thermal and resistive properties of these and other candidate materials should enable us to characterize the pulse shape and subsequently predict the ultimate performance. We are building a compact adiabatic demagnetization refrigerator for conveniently reaching 0.1°K in the laboratory and for use in future satellite-borne missions. A description of this instrument together with results from our most recent experiments will be presented.

scholarly journals Spectroscopic characterization of a thermodynamically stable doubly charged diatomic molecule: MgAr2+

2021 ◽  
Author(s):  
Dominik Wehrli ◽  
Matthieu Génévriez ◽  
Frédéric Merkt
Keyword(s):  
High Resolution ◽  
Diatomic Molecule ◽  
Spectroscopic Characterization ◽  
New Method ◽  
High Resolution Spectroscopy ◽  
Singly Charged ◽  
Doubly Charged

We present a new method to study doubly charged molecules relying on high-resolution spectroscopy of the singly charged parent cation, and report on the first spectroscopic characterization of a thermodynamically stable diatomic dication, MgAr2+.

scholarly journals The Voyage of Metals in the Universe from Cosmological to Planetary Scales: the need for a Very High-Resolution, High Throughput Soft X-ray Spectrometer

2021 ◽  
Author(s):  
F. Nicastro ◽  
J. Kaastra ◽  
C. Argiroffi ◽  
E. Behar ◽  
S. Bianchi ◽  
...  
Keyword(s):  
Chemical Composition ◽  
High Resolution ◽  
Deep Understanding ◽  
High Resolution Spectroscopy ◽  
X Ray ◽  
Viable Solution ◽  
Surrounding Space ◽  
Nuclear Processes ◽  
The Universe ◽  
Very High

AbstractMetals form an essential part of the Universe at all scales. Without metals we would not exist, and the Universe would look completely different. Metals are primarily produced via nuclear processes in stars, and spread out through winds or explosions, which pollute the surrounding space. The wanderings of metals in-and-out of astronomical objects are crucial in determining their own evolution and thus that of the Universe as a whole. Detecting metals and assessing their relative and absolute abundances and energetics can thus be used to trace the evolution of these cosmic components. The scope of this paper is to highlight the most important open astrophysical problems that will be central in the next decades and for which a deep understanding of the Universe’s wandering metals, their physical and kinematical states, and their chemical composition represents the only viable solution. The majority of these studies can only be efficiently performed through High Resolution Spectroscopy in the soft X-ray band.

scholarly journals None sharp corner localized surface plasmons resonance based ultrathin metasurface single layer quarter wave plate

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Qinyu Qian ◽  
Pengfei Liu ◽  
Li Fan ◽  
Liang Zhao ◽  
Chinhua Wang
Keyword(s):  
Surface Plasmons ◽  
Amplitude Ratio ◽  
Single Layer ◽  
Quarter Wave Plate ◽  
Localized Surface Plasmons ◽  
Sharp Corner ◽  
Wave Plate ◽  
Nanophotonic Devices ◽  
Elliptical Ring ◽  
Quarter Wave

AbstractWe report on a non-sharp-corner quarter wave plate (NCQW) within the single layer of only 8 nm thickness structured by the Ag hollow elliptical ring array, where the strong localized surface plasmons (LSP) resonances are excited. By manipulating the parameters of the hollow elliptical ring, the transmitted amplitude and phase of the two orthogonal components are well controlled. The phase difference of π/2 and amplitude ratio of 1 is realized simultaneously at the wavelength of 834 nm with the transmission of 0.46. The proposed NCQW also works well in an ultrawide wavelength band of 110 nm, which suggests an efficient way of exciting LSP resonances and designing wave plates, and provides a great potential for advanced nanophotonic devices and integrated photonic systems.

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