# Propagation of Terahertz Surface Plasmon Polaritons in a Dielectric Fiber with a Metal Wire Core

## Abstract

**:**

## 1. Introduction

## 2. Problem Formulation

_{z}[31]:

_{1}and A

_{2}are the amplitude coefficients, ${I}_{0}$ and ${K}_{0}$ are the modified Bessel functions of the first and second kind, ${\eta}^{2}=\left(\frac{{\omega}^{2}}{{c}^{2}}\right){\epsilon}_{p}-{\beta}^{2}$, ${\eta}_{0}^{2}=\left(\frac{{\omega}^{2}}{{c}^{2}}\right){\epsilon}_{d}-{\beta}^{2}$.

## 3. Velocity and Propagation Distance of Surface Wave as Function of Wire Conductivity

#### Effect of a Dielectric Coating

^{−1}.

^{−1}at an operating frequency of f = 1 THz. In [39], a low-loss THz waveguide based on a photonic crystal structure with an average power loss of 0.02 cm

^{−1}was designed and manufactured by 3D printing.

## 4. Conclusions

## Funding

## Data Availability Statement

## Conflicts of Interest

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**Figure 1.**The schematic view of a dielectric fiber with a metal wire core (

**a**) and its cross section (

**b**).

**Figure 2.**Field intensity distributions at the wire-dielectric boundary. (

**a**)—inside wire; (

**b**,

**c**)—outside wire; ${\epsilon}_{d}=1.0\left(\mathbf{b}\right);{\epsilon}_{d}=2.56\left(\mathbf{c}\right);$ ${r}_{0}=100\mathsf{\mu}\mathrm{m},$σ = ${10}^{7}{\Omega}^{-1}{\mathrm{m}}^{-1}$, $\omega =0.9\mathrm{THz}$, λ = 2.1 mm.

**Figure 3.**The phase velocity (

**a**) and attenuation length (

**b**) as function of conductivity. 1—ω = 0.9 THz, 2—ω = 1.1 THz.

**Figure 4.**The attenuation length as a function of conductivity. ω = 0.9 THz; 1—bare metal wire, 2—coated metal wire. ${r}_{0}=100\mathsf{\mu}\mathrm{m}$.

**Figure 5.**The phase velocity (

**a**) and attenuation length (

**b**) as a function of frequency. ${r}_{0}=10\mathsf{\mu}\mathrm{m},$σ = 1.5$\xb7{10}^{7}{\mathsf{\Omega}}^{-1}{\mathrm{m}}^{-1}$.

**Figure 6.**The attenuation length as a function of conductivity. ${r}_{0}=10\mathsf{\mu}\mathrm{m},\omega =10\mathrm{THz}$, 1—air; 2—coated metal wire.

**Figure 7.**The phase velocity (

**a**) and attenuation length (

**b**) as a function of conductivity. ${r}_{0}=100\mathsf{\mu}\mathrm{m}.$ Dashed line line—ω = 0.9 THz, solid line—ω = 1.0 THz.

**Figure 8.**The velocities (

**a**) and attenuation lengths (

**b**) as a function of conductivity. 1—ω = 1 THz; 2—ω = 5 THz; 3—ω = 10 THz; ${r}_{0}=10\mathsf{\mu}\mathrm{m}$.

**Figure 9.**The velocities (

**a**) and attenuation lengths (

**b**) as a function of conductivity. ω = 1 THz; 1—${r}_{0}=1\mathsf{\mu}\mathrm{m}$ ; 2—${r}_{0}=5\mathsf{\mu}\mathrm{m}$; 3—${r}_{0}=10\mathsf{\mu}\mathrm{m}$. ${\epsilon}_{d}^{\prime}=2.56;{\epsilon}_{d}^{\u2033}=0$.

**Figure 10.**The velocities (

**a**) and attenuation lengths (

**b**) as a function of conductivity. ω = 1 THz; 1—${r}_{0}=1\mathsf{\mu}\mathrm{m}$; 2—${r}_{0}=5\mathsf{\mu}\mathrm{m}$; 3—${r}_{0}=10\mathsf{\mu}\mathrm{m}$. ${\epsilon}_{d}^{\prime}=2.56;{\epsilon}_{d}^{\u2033}=0.01$.

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**MDPI and ACS Style**

Petrov, N.I.
Propagation of Terahertz Surface Plasmon Polaritons in a Dielectric Fiber with a Metal Wire Core. *Fibers* **2022**, *10*, 89.
https://doi.org/10.3390/fib10100089

**AMA Style**

Petrov NI.
Propagation of Terahertz Surface Plasmon Polaritons in a Dielectric Fiber with a Metal Wire Core. *Fibers*. 2022; 10(10):89.
https://doi.org/10.3390/fib10100089

**Chicago/Turabian Style**

Petrov, Nikolai I.
2022. "Propagation of Terahertz Surface Plasmon Polaritons in a Dielectric Fiber with a Metal Wire Core" *Fibers* 10, no. 10: 89.
https://doi.org/10.3390/fib10100089