Four-channel CWDM device on a thin-film lithium niobate platform using an angled multimode interferometer structure

Gengxin Chen; Ziliang Ruan; Zong Wang; Pucheng Huang; Changjian Guo; Daoxin Dai; Kaixuan Chen; Liu Liu

doi:10.1364/PRJ.438816

Photonics Research, Volume. 10, Issue 1, 8(2022)

Four-channel CWDM device on a thin-film lithium niobate platform using an angled multimode interferometer structure

Gengxin Chen¹, Ziliang Ruan¹, Zong Wang², Pucheng Huang², Changjian Guo^2,3, Daoxin Dai¹, Kaixuan Chen^2,3,4, and Liu Liu^1、*

Author Affiliations

¹State Key Laboratory for Modern Optical Instrumentation, College of Optical Science and Engineering, International Research Center for Advanced Photonics, Zhejiang University, Hangzhou 310058, China

²Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Higher-Education Mega-Center, Guangzhou 510006, China

³National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou 510006, China

⁴e-mail: chenkaixuan@m.scnu.edu.cn

show less

Figures & Tables(10)

Fig. 1. (a) Schematic diagram of the four-channel CWDM on TFLN based on an angled MMI structure. (b) Calculated wavelength dependence of the neff curve for the first five TE modes at WMMI=17.54 μm. (c) Calculated neff curve of the first five TE modes at different WMMI at a wavelength of 1300 nm. (d) Simulated light propagation in the proposed angled MMI structure.

Download full size

View in Article

Fig. 2. Simulated spectral responses of the proposed CWDM device with different tilted angles: (a) θ=0.17 rad, (b) θ=0.15 rad, and (c) θ=0.23 rad. The output waveguide spacing here is Δx=0.88 μm.

Download full size

View in Article

Fig. 3. Simulated spectral responses of the proposed CWDM device for (a) θ=0.15 rad, Δx=0.1 μm and (b) θ=0.23 rad, Δx=2.79 μm.

Download full size

View in Article

Fig. 4. Simulated fabrication tolerance of the proposed CWDM device with changes (a) in L1 of ΔL1 from −1 to +1 μm, (b) in WMMI of ΔWMMI from −0.04 to +0.04 μm, (c) only in input waveguide width Wa of ΔWa from −2.4 to +2.4 μm, (d) in both input and output waveguide widths Wa of ΔWa from −4 to +4 μm, (e) in t of Δt from −20 to +20 nm, and (f) in h of Δh from −20 to +20 nm for channel #1. Except for the one studied, the rest of the structural parameters are unchanged as shown in Table 1.

Download full size

View in Article

Fig. 5. (a) Microscope image of a fabricated device. Scanning electron microscope images of (b) input coupling grating, (c) input waveguide, (d) output waveguides, and (e) output coupling gratings.

Download full size

View in Article

Fig. 6. (a) Schematic of the measurement setup. (b) Measured spectral response of the fabricated CWDM device. (c) Measured peak wavelength positions (red dots), linear fit (red dotted line), and simulated peak wavelength positions (blue dots) for channel #1 with variations in WMMI.

Download full size

View in Article

Table 1. Optimized Structural Parameters for the Four-Channel CWDM Device on TFLN
View table
View in Article
Table 1. Optimized Structural Parameters for the Four-Channel CWDM Device on TFLN
$W_{MMI} = 17.54 μm$ , $W_{a} = 5.54 μm$ , $θ = 0.17 rad$ , $Δ x = 0.88 μm$ , $i = 1, 2, 3, 4$
Channel # 1 2 3 4
$λ_{i}$ [nm] 1271 1291 1311 1331
$L_{i}$ [μm] 2054 2017 1980 1943

Table 2. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 2(b) and 2(c)

View table

View in Article

Table 2. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 2(b) and 2(c)

$W_{MMI} = 17.54 μm$ , $W_{a} = 5.54 μm$ , $i = 1, 2, 3, 4$
Channel #		1	2	3	4
$θ = 0.15 rad$	$λ_{i}$ [nm]	1265	1287	1309	1331
$Δ x = 0.88 μm$	$L_{i}$ [μm]	2064	2023	1982	1941
$θ = 0.23 rad$	$λ_{i}$ [nm]	1277	1292	1307	1322
$Δ x = 0.88 μm$	$L_{i}$ [μm]	2041	2013	1985	1957

Table 3. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 3(a) and 3(b)

View table

View in Article

Table 3. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 3(a) and 3(b)

$W_{MMI} = 17.54 μm$ , $W_{a} = 5.54 μm$ , $i = 1, 2, 3, 4$
Channel #		1	2	3	4
$θ = 0.15 rad$	$λ_{i}$ [nm]	1271	1291	1311	1331
$Δ x = 0.10 μm$	$L_{i}$ [μm]	2053	2015	1977	1939
$θ = 0.23 rad$	$λ_{i}$ [nm]	1271	1291	1311	1331
$Δ x = 2.79 μm$	$L_{i}$ [μm]	2053	2017	1981	1945

Table 4. Performance Comparison of Different Types of CWDM Devices

View table

View in Article

Table 4. Performance Comparison of Different Types of CWDM Devices

Device	Footprint ( ${mm}^{2}$ )	Channel Amount/Spacing (nm)	Insertion Loss (dB)	${XT}_{center}$ ^a (dB)	${BW}_{3 dB}$
Si [19] PCG	0.25 × 0.16	4/20.2	2.2	23.3	NM^b
Si [20] CMZI	0.3 × 0.1	4/20	$\sim 1$	$\sim 20$	19
Si [22] MMI	0.012 × 1.21	4/21	2	20	12
Si [25] MWG^c	0.6 × 0.04	4/20	$\sim 1$	$\sim 20$	$\sim 15$ ^d
SiN [26] CMZI	1 × 0.6	4/20	$\sim 1.8$	15–24	$\sim 12$ ^d
USRN [27] CVG^e	0.0006 × 8^f	8/20	1	25	7.7
SiN [23] MMI	0.02 × 1.7	4/19	1.5	16–27	11
SiN [21] MWG	0.23 × 1.95	4/20	$< 1.08$	18	10^d
This work	0.02 × 2.1	4/20	$< 0.72$	$\sim 18$	$\sim 12.1$

Tools

Get Citation

Copy Citation Text

Gengxin Chen, Ziliang Ruan, Zong Wang, Pucheng Huang, Changjian Guo, Daoxin Dai, Kaixuan Chen, Liu Liu, "Four-channel CWDM device on a thin-film lithium niobate platform using an angled multimode interferometer structure," Photonics Res. 10, 8 (2022)

Download Citation

EndNote(RIS)BibTex Plain Text

Set citation alerts for article

Save article for my favorites

Paper Information

Category: Integrated Optics

Received: Jul. 27, 2021

Accepted: Oct. 25, 2021

Published Online: Dec. 8, 2021

The Author Email: Liu Liu (liuliuopt@zju.edu.cn)

DOI:10.1364/PRJ.438816

Topics

laser devices and laser physics

Lasers and Laser Optics

Laser physics

laser manufacturing

Instrumentation, Measurement and Metrology

Table 1. Optimized Structural Parameters for the Four-Channel CWDM Device on TFLN

Table 1. Optimized Structural Parameters for the Four-Channel CWDM Device on TFLN

Table 2. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 2(b) and 2(c)

Table 2. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 2(b) and 2(c)

Table 3. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 3(a) and 3(b)

Table 3. Structural Parameters of the Four-Channel CWDM Device on TFLN for Figs. 3(a) and 3(b)

Table 4. Performance Comparison of Different Types of CWDM Devices

Table 4. Performance Comparison of Different Types of CWDM Devices