Abstract

Photoconductive antennas (PCAs) have extensive industrial applications as terahertz (THz) emitters. It is an established belief that the existence of periodic metallic structures at the edges of the antenna electrodes, as is the case in plasmonic PCAs, can remarkably improve the antenna performance. In this paper, we start with introducing a theoretical model for the analysis of plasmonic PCAs, considering the effect of the screening electric field as well. The results of the model, applied to a plasmonic PCA with periodic rectangular rods, agree well with the experimental measurements. Finally, guided by the theoretical model, a plasmonic PCA with buried stepped rods is proposed for improved performance in THz radiation power and in generated current. The enhancements turn out to be the consequence of two welcoming phenomena: First, according to the theoretical model (as well as independent finite element simulations), for the PCA with buried stepped rods, the power transmitted into the low-temperature-grown GaAs (LT-GaAs) substrate is 70% in the THz wavelength range and complete at an optical wavelength of 0.8 μm and 40% enhancement in the optical power transmission as compared to the rectangular rods. Second, in comparison with the rectangular rods, a larger portion of the carriers are generated in the vicinity of the rod corners, which favorably contributes to the current generation but does not contribute much to the unwanted screening electric field.

© 2016 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Increase in terahertz radiation power of plasmonic photoconductive antennas by embedding buried three-stepped rods in electrodes

Mohammadreza Khorshidi, Sajad Zafari, and Gholamreza Dadashzadeh
Opt. Express 27(16) 22327-22338 (2019)

Comparative study of equivalent circuit models for photoconductive antennas

O. A. Castañeda-Uribe, C. A. Criollo, S. Winnerl, M. Helm, and A. Avila
Opt. Express 26(22) 29017-29031 (2018)

Computational modeling of plasmonic thin-film terahertz photoconductive antennas

Nathan Burford and Magda El-Shenawee
J. Opt. Soc. Am. B 33(4) 748-759 (2016)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (11)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (1)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (19)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription