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arXiv · 1604.07376

A Modified $8f$ Geometry With Reduced Optical Aberrations For Improved Time Domain Terahertz Spectroscopy

N. J. Laurita·Bing Cheng·R. Barkhouser·V. A. Neumann·N. P. Armitage
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Abstract

We present a modified $8f$ geometry for time domain terahertz (THz) spectroscopy (TDTS) experiments. We show, through simulations and data, that a simple rearranging of the off-axis parabolic mirrors, which are typically used to focus and direct THz radiation in TDTS experiments, results in a nearly 40% reduction in the THz focal spot diameter. This effect stems from significant reduction of the principle optical aberrations which are enhanced in the conventional $8f$ geometry but partially compensated in the modified $8f$ experimental setup. We compare data from our home-built TDTS spectrometer in the modified $8f$ geometry to that of previous iterations that were designed in the conventional $8f$ geometry to demonstrate the effect.

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N. J. Laurita, Bing Cheng, R. Barkhouser, V. A. Neumann, N. P. Armitage. 2016-04-25. A Modified $8f$ Geometry With Reduced Optical Aberrations For Improved Time Domain Terahertz Spectroscopy. https://doi.org/10.1007/s10762-016-0281-x

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