Thickness-Controlled Ti Optical Filters Designed for Tunable Terahertz Technology
Yükleniyor...
Tarih
15.02.2025
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Physica Status Solidi b (Wiley)
Erişim Hakkı
info:eu-repo/semantics/embargoedAccess
Özet
Herein, titanium (Ti) thin films deposited by a vacuum ion coating technique
under a high vacuum pressure of 10 5 mbar are designed to perform as optical
filters operatives in the terahertz frequency domain. The performance of these
amorphous optical filters is controlled by varying the filter thickness in the range
of 100–500 nm. Increasing the thickness of the filters decreases the optical
transmittance, the absorption coefficient, the optical conductivity (σ), the terahertz
cutoff frequency ( fT), the drift mobility, and the free carrier concentration.
The thickness-based bulk limit of these filters is ≈300 nm. On the other hand, the
increase in the optical filter thickness results in an increase the dielectric constant.
Drude–Lorentz analyses on σ of the filters have shown the domination of
four oscillators with oscillator frequencies of 1016, 859, 508, and 317 THz. These
oscillators guarantee the good response of the Ti optical filters to optical excitations
in the infrared, visible, and UV spectral domains. Based on the filter
thickness, an extremely wide range of fT extending from ≈3.8 to 1248 THz can be
achieved. The wide tunability of fT and σ of the Ti optical filters makes them
promising for terahertz applications.
Açıklama
Anahtar Kelimeler
Drude–Lorentz, optical conductivity, terahertz, thickness, Ti thin films
Kaynak
Physica Status Solidi b
WoS Q Değeri
Scopus Q Değeri
Cilt
Sayı
2400648
