<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>The electro-optic effect is considered very important in optical communication systems. The small optical confinement factor is attributed to the weak overlap between the electric field and optical wave and hence the optical signal is not efficiently modulated. In this paper, the problem of the small optical confinement factor in the Mach–Zehnder modulator based on lithium niobate (LN) which is deeply studied. The data were analyzed through a proposed mathematical model to explain the relationship between the change in the ordinary negative refractive index and the confinement factor. The system is improved using a small length of the modulator arm as only 3 to 8 µm, low driving power of about 4 V/µm, a large change in the negative ordinary refractive index of about—0.2 × 10<sup>−7</sup>, and a compact optical modulator. This can reflect a strong optical confinement factor when the electric field is applied to the electrodes of the optical modulator.</p>
</abstract>

The electro-optic effect is considered very important in optical communication systems. The small optical confinement factor is attributed to the weak overlap between the electric field and optical wave and hence the optical signal is not efficiently modulated. In this paper, the problem of the small optical confinement factor in the Mach–Zehnder modulator based on lithium niobate (LN) which is deeply studied. The data were analyzed through a proposed mathematical model to explain the relationship between the change in the ordinary negative refractive index and the confinement factor. The system is improved using a small length of the modulator arm as only 3 to 8 µm, low driving power of about 4 V/µm, a large change in the negative ordinary refractive index of about—0.2 × 10−7, and a compact optical modulator. This can reflect a strong optical confinement factor when the electric field is applied to the electrodes of the optical modulator.

The ordinary negative changing refractive index for estimation of optical confinement factor

Department of Communications, College of Engineering

International Journal on Smart Sensing and Intelligent Systems

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

The electro-optic effect is considered very important in optical communication systems. The small optical confinement factor is attributed to the weak overlap...

r₃₃ (pm/V)	Wavelength (nm)	n_o	Reference
31	633	2.2864	(Casson et al., 2004)
25	1560	2.2108	(Casson et al., 2004)

Reference	Δn	L	d	ΔØ	E	Γ	Modulator type
(Qi and Li, 2020) and (He et al., 2019)	Large	Large In mm	Small	π/2	E = V/d	Large	Transvers
This work	Large	Small In μm	–	π	E = V/L	Large	Longitudinal

The ordinary negative changing refractive index for estimation of optical confinement factor

Article Category: Article

Published Online: Jun 29, 2022

Page range: -

Received: Dec 23, 2021

DOI: https://doi.org/10.2478/ijssis-2022-0009

Keywords
Electro-optic effect, Lithium niobate LN, Mach–Zehnder modulator MZM, Optical confinement factor

© 2022 Ahmad S. Abdullah et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Electro-optic coefficients (r33), refractive index (no) and wavelengths (λ), for LN.4.

The comparison between the reference paper (Chang et al., 2017; Qi and Li, 2020) and this work.

The ordinary negative changing refractive index for estimation of optical confinement factor

Article Category: Article

Published Online: Jun 29, 2022

Page range: -

Received: Dec 23, 2021

DOI: https://doi.org/10.2478/ijssis-2022-0009

KeywordsElectro-optic effect, Lithium niobate LN, Mach–Zehnder modulator MZM, Optical confinement factor

© 2022 Ahmad S. Abdullah et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Electro-optic coefficients (r33), refractive index (no) and wavelengths (λ), for LN.4.

The comparison between the reference paper (Chang et al., 2017; Qi and Li, 2020) and this work.

Keywords
Electro-optic effect, Lithium niobate LN, Mach–Zehnder modulator MZM, Optical confinement factor