Abstract-Terahertz spectroscopy of human skin tissue models with different melanin content

Xomalin G. Peralta, Dawn Lipscomb, Gerald J. Wilmink, and Ibtissam Echchgadda

Fig. 1 Human skin tissue model. (a) Schematic illustration of the wells used for culturing skin tissue models. (b-d) Top down digital photographs of (b) Asian, (c) Black, and (d) Caucasian skin tissue models on Day 16.

https://www.osapublishing.org/boe/abstract.cfm?uri=boe-10-6-2942

Terahertz imaging has been proposed for burns and skin cancer identification. However, the role of melanocytes, melanosomes, melanin content and distribution in determining the terahertz optical properties of human skin has not been investigated. We use terahertz time domain spectroscopy to measure the optical properties of in vitro pigmented human skin tissue models from Asian, Black, and Caucasian donors. Spectra were collected at various time intervals and used to extract the absorption coefficient and index of refraction at terahertz frequencies. Our results indicate that the degree of cell differentiation and type of donor both contribute to the measured terahertz optical properties.

Abstract-Lattice-induced modulators at terahertz frequencies

Guillermo A. Naranjo and Xomalin G. Peralta

https://www.osapublishing.org/ol/abstract.cfm?uri=ol-42-23-4780

We measured the transmission spectra of an array of split-ring resonators (SRRs) up to 10 terahertz for parallel and perpendicular polarizations. Calculations of the lattice and plasmon mode dispersion relations, in combination with electromagnetic simulations, confirm the presence of multiple higher-order lattice and plasmon modes. We modify the quality factor of higher-order plasmon resonances by modulating the lattice-plasmon mode coupling via changes in the period of the array. We also propose single frequency switches and a broadband dual-state amplitude modulator based on structured illumination that actively modifies the period of the SRR array.

© 2017 Optical Society of America

Abstract-Terahertz electrical and optical properties of LiNbO3 single crystal thin films

Moumita Dutta, Xomalin G. Peralta, Amar Bhalla, Ruyan Guo

The Univ. of Texas at San Antonio (United States)

Carol Ellis

Southwest Research Institute (United States)

Proc. SPIE 9586, Photonic Fiber and Crystal Devices: Advances in Materials and Innovations in Device Applications IX, 958608 (August 26, 2015); doi:10.1117/12.2188933

http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=2432423

A study of Terahertz response of single crystal LiNbO3 thin films subjected to different structural and experimental configuration has been conducted in this work. In this work z-cut and x-cut ion-sliced Lithium Niobate thin films with and without embedded electrodes have been studied employing both Transmission and Reflection mode of Terahertz Spectroscopy along with z-cut single crystal in bulk form. The measurements have been performed in room temperature to probe distinctive THz-material interactions in the frequency range of 0.1-3 THz (3.34cm-1 - 100cm-1). The information thus obtained from the experimental investigation has been used to deduce a conclusive study on the influence of different polar domains on electrical and optical properties in THz frequency regime. Single Lorentzian oscillator model has also been used to define the THz signature thus acquired

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