Abstract
We demonstrate a high dynamic range (DR) Fourier-transform-based terahertz (THz) spectrometer by combining a THz photomultiplier tube (PMT) with a metasurface and a conventional Michelson interferometer. Because the THz-PMT response depends on the incident electric-field strength following the Fowler–Nordheim equation, we can directly obtain an electric field interferogram without any synchronized optical probe pulse in contrast to conventional THz-time-domain-spectroscopy (THz-TDS). The DR of the corresponding power spectrum using the proposed method was 4.6 × 105 without the use of a lock-in amplifier. The complex refractive index of a quartz glass plate obtained using the proposed method was in good agreement with the results of conventional THz-TDS.
Original language | English |
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Journal | Optics Express |
Volume | 32 |
Issue number | 7 |
Pages (from-to) | 12774-12782 |
ISSN | 1094-4087 |
DOIs | |
Publication status | Published - 25 Mar 2024 |