University of California, San Diego Uses TeraView's Instrument for Near-field Microscopy

Cambridge, UK – 27th November, 2012

TeraView, the pioneer and leader in terahertz solutions and technology, has successfully delivered a TPS Spectra 3000 system to the Infrared Laboratory for Novel Infrared and Magnetic Materials at the University of California, San Diego, founded and let by Professor Dimitri Basov.

Professor Basov and his laboratory are world leaders in the use of optical and infrared methods to investigate the characteristic energies and physics of strongly correlated electron systems, magnetic semiconductors, superconductivity and other novel electromagnetic materials.  Prof Basov’s team will utilize the system for both routine characterisation of material systems at low temperatures, as well as a new project to develop a near-field microscopy system utilising terahertz time-domain techniques for spectroscopic measurements in ultra-high vacuum. TeraView has supplied a special breadboard version of its TPS Spectra 3000 time-domain terahertz spectrometer for the project.

Professor Basov is chair of the Department of Physics at the University of California at San Diego and has a long and substantive track record in the use of terahertz, infrared and optical methods applied to fundamental studies in condensed matter physics. He is a recipient of numerous prizes, including most recently the Frank Isakson Prize for Optical Effects in Solids from the American Physical Society in 2012.

This new project adds to TeraView’s growing installed base in the United States, and helps strengthen its position as the market leader for terahertz systems. Dr Don Arnone, TeraView’s CEO stated: ‘This collaboration with a prestigious research group highlights TeraView’s position as major supplier of terahertz systems and indicates the continued growth in the use of terahertz as a valuable tool for both fundamental physics as well as applications development in exciting areas such as terahertz microscopy'.

Validation of Terahertz Coating Thickness Measurements Using X-ray Microtomography

Isabelle-Sophie Russe †‡, Daniela Brock †‡, Klaus Knop ‡, Peter Kleinebudde ‡, and J. Axel Zeitler *†

^† Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA, U.K.

^‡ Institute of Pharmaceutics and Biopharmaceutics, Heinrich-Heine-University, Universitätsstrasse 1, 40225 Düsseldorf, Germany

Mol. Pharmaceutics, DOI: 10.1021/mp300383y Publication Date (Web): November 1, 2012

Abstact

Terahertz pulsed imaging (TPI) is a recently developed nondestructive and noncontact method to measure the coating thickness of coated pharmaceutical tablets. The method requires no calibration in order to resolve the coating structure of tablets. The relative coating thickness over a tablet surface or between different tablets of the same batch can be determined with high precision. However, in order to determine the absolute coating thickness accurately the refractive index, n, of the coating layer needs to be known. For all published studies to date the value of n was based on estimates or bulk measurements, which were based on the assumption that n is constant for a given coating formulation. We have developed a measurement technique using X-ray microtomography to independently quantify the coating thickness. These data were then used to validate the terahertz imaging results, and we found that the intertablet variation of n for coating layers of 25–270 μm thickness is less than 4% and that there is less than 3% intratablet variation in n. Based on our results we estimate that, depending on the pigment content, the absolute value of n in a typical pharmaceutical coating formulation will be in the range of 1.45 < n < 2.01. We conclude that TPI is a robust technique and that, due to its very simple measurement principle, it is an ideal measurement technique to quantify the coating thickness in process control and quality monitoring applications.

To learn more about TeraView see http://www.teraview.com/applications/pharmaceutical/index.html

Terahertz spectroscopy in the pseudo-Kagome system Cu3Bi(SeO3)2O2Br

THz spectroscopy in the pseudo-Kagome system Cu3Bi(SeO3)2O2Br

Zhe Wang, M. Schmidt, Y. Goncharov, V. Tsurkan, H.-A. Krug von Nidda, A. Loidl, J. Deisenhofer

(Submitted on 4 Oct 2012 (v1), last revised 13 Nov 2012 (this version, v2))

Terahertz (THz) transmission spectra have been measured as function of temperature and magnetic field on single crystals of Cu3Bi(SeO3)2O2Br. In the time-domain THz spectra without magnetic field, two resonance absorptions are observed below the magnetic ordering temperature T_N~27.4 K. The corresponding resonance frequencies increase with decreasing temperature and reach energies of 1.28 and 1.23 meV at 3.5 K. Multi-frequency electron spin resonance transmission spectra as a function of applied magnetic field show the field dependence of four magnetic resonance modes, which can be modeled as a ferromagnetic resonance including demagnetization and anisotropy effects.

View full article http://arxiv.org/pdf/1210.1343v2.pdf

.......Time-domain THz transmission measurements were carried out on a 2 × 2 × 0.3 mm3 single crystal for 3.5 K <T < 300 K using a TPS spectra 3000 spectrometer with f/2 focusing optics (TeraView, Ltd.). ...

Register for free at http://www.teraview.com/info/contact-us.php

For more information about the Spectra 3000 used for these measurements see http://www.teraview.com/products/index.html

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Complex THz Reflectance Spectra of Hexogen Measured for Various Surfaces

N. Palka

Institute of Optoelectronics, Military University of Technology S. Kaliskiego 2, 00-908 Warsaw, Poland

ACTA PHYSICA POLONICA A 122, 854-7 (2012)

Abstract

In this paper, we report on measurements of reflection spectra of hexogen (RDX) by means of time domain spectroscopy. We analyzed both phase and amplitude of reflected impulses for three cases: detuning, samples with rough surfaces and samples with curved surfaces. It can be concluded that both spectral characteristics can be applied for identification of explosives in the reflection configuration.

For full paper see http://przyrbwn.icm.edu.pl/APP/PDF/122/a122z5p16.pdf

Register for free at http://www.teraview.com/info/contact-us.php

For more information about the Spectra 3000 used for these measurements see http://www.teraview.com/products/terahertz-pulsed-spectra-3000/terahertz-standoff-detection.html
 
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Terahertz Spectra of Explosives Measured by Optical Parametric Oscillator-Based System and Time Domain Spectroscopy

N. Palka, T. Trzcinski and M. Szustakowski
Institute of Optoelectronics, Military University of Technology, S. Kaliskiego 2, 00-908 Warsaw, Poland

ACTA PHYSICA POLONICA A, 122, 946 (2012)

Abstact

In this paper, we report on measurements of absorption spectra of hexogen, penthrite, and octogen. The measurements were carried out by means of time domain spectroscopy and compared to spectra obtained from a setup, which bases on an optical parametric oscillator combined with a Golay cell. For time domain spectroscopy measurement, Teraview TPS 3000 unit with accessories in transmission con figuration was used.


"TDS is a commonly used technique in THz range to measure transmission spectra of materials. In our measurements we used a commercially available spectrometer TPS 3000 from TeraView."

for full paper see http://przyrbwn.icm.edu.pl/APP/PDF/122/a122z5p16.pdf


Register for free at http://www.teraview.com/info/contact-us.php


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