Plasmonic interactions at the Pb/SeO2 interfaces designed as terahertz/gigahertz optical receivers

Pb/FeSe Interfaces Designed for Optical Communication Technology

“…[10] The free carrier absorption in PFS films is suppressed due to the formation of PbSe layer (observed by XRD technique). Formation of lead selenide decreases the amount of broken bonds (perform as defects) that in turn decreases the number of free electrons available for electronic transitions, [21,25] It was previously observed in Se based materials containing excess selenium in its composition. As for example interaction of Pb and Ag with SeO 2 suppressed the free carrier absorption in the films, [21,25] On the other hand information about the electronic transitions in GFS and PFS films is obtained from the Tauc's equation fittings ((𝛼E) p ∝ (E − E g ) for indirect (p = 1∕2) and direct (p = 2) allowed transitions, [10,25] The fittings displayed in Figure 3b,c indicate crossings on the 𝐸−axes, revealing direct and indirect energy bandgap values of 2.49 and 2.80 eV for GFS, along with corresponding values of 2.41 and 2.50 eV for PFS films.…”

“…0.53m o , [10,25] it was possible to reproduce the experimental optical conductivity data of PFS optical resonators. The theoretically estimated optical conductivity is shown by black colored circles in Figure 5a.…”

“…[ 10 ] The free carrier absorption in PFS films is suppressed due to the formation of PbSe layer (observed by XRD technique). Formation of lead selenide decreases the amount of broken bonds (perform as defects) that in turn decreases the number of free electrons available for electronic transitions, [ 21,25 ] It was previously observed in Se based materials containing excess selenium in its composition. As for example interaction of Pb and Ag with SeO 2 suppressed the free carrier absorption in the films, [ 21,25 ]…”

“…On the other hand information about the electronic transitions in GFS and PFS films is obtained from the Tauc's equation fittings ($${( {\alpha E} )}^p \propto (E - {E}_{\mathrm{g}}$$) for indirect ($$p\ = \ 1/2$$) and direct ($$p\ = \ 2$$) allowed transitions, [ 10,25 ] The fittings displayed in Figure 3b,c indicate crossings on the 𝐸−axes, revealing direct and indirect energy bandgap values of 2.49 and 2.80 eV for GFS, along with corresponding values of 2.41 and 2.50 eV for PFS films. The shrinkage in the values of the energy bandgap is a reason for the enhanced light absorption.…”

Growth and Characterization of Lanthanum Germanide Thin Films by the Thermal Evaporation Technique

“…Such values are ideal for fabricating tunneling diodes. These diodes find application in electronic circuits as microwave resonators [ 45 ] and as sources of negative differential resistances which are used in microwave communication technology.…”