Terahertz quantum cascade laser based optical coherence tomography
Name
Hu_Terahertz quantum.pdf
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2.28 MB
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Adobe PDF
Checksum (MD5)
7182cbc7054977dcdaa6b4cdc9111893
Author(s)
Lee, Alan
Kao, Tsung-Yu
Hu, Qing
Reno, John L.
Date Issued
February 2013
Journal
Proceedings of SPIE--the International Society for Optical Engineering
Publisher
SPIE
Citation
Lee, Alan W. M., Tsung-Yu Kao, Qing Hu, and John L. Reno
" Terahertz quantum cascade laser based optical coherence tomography ", Proc. SPIE 8585, Terahertz and Ultrashort Electromagnetic Pulses for Biomedical Applications, 858508 (February 23, 2013). ©2013 SPIE.
Version
Final published version
Abstract
The interfaces of a dielectric sample are resolved in reflection geometry using light from a frequency agile array of terahertz quantum-cascade lasers. The terahertz source is a 10-element linear array of third-order distributed feedback QCLs emitting at discrete frequencies from 2.08 to 2.4 THz. Emission from the array is collimated and sent through a Michelson interferometer, with the sample placed in one of the arms. Interference signals collected at each frequency are used to reconstruct an interferogram and detect the interfaces in the sample. Due to the long coherence length of the source, the interferometer arms need not be adjusted to the zero-path delay. A depth resolution of 360 μm in the dielectric is achieved with further potential improvement through improved frequency coverage of the array. The entire experiment footprint is <1 m x 1 m with the source operated in a compact, closed-cycle cryocooler.
MIT Department
Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1117/12.2001127
