1
|
Liu Z, Dong Y, Xu Y, Zhang B, Ni Y. Low loss and ultra-broadband design of an integrated 3 dB power splitter centered at 2 µm. APPLIED OPTICS 2024; 63:662-667. [PMID: 38294377 DOI: 10.1364/ao.510814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/19/2023] [Indexed: 02/01/2024]
Abstract
Because chemical gas is sensitive to absorption in the 2 µm band, and 2 µm matches the absorption band of the remote sensing material, many remote sensors and optical sensors are designed to operate in the 2 µm wavelength region. In this paper, we designed an integrated 3 dB power splitter centered at 2 µm. The study of this device is built on a silicon-on-insulator (SOI) platform. We introduced a subwavelength grating (SWG) to improve the performance of the device. We used the three-dimensional finite-difference time-domain (3D FDTD) method to analyze the effect of the structure on the power splitter. The insertion loss (IL) of the fundamental TE mode is only 0.04 dB at 2 µm and its bandwidth of IL <0.45d B is 940 nm (1570-2510 nm). It is suitable for multidomain and all-band photonic integrated circuits at 2 µm.
Collapse
|
2
|
Shahbaz M, Butt MA, Piramidowicz R. Breakthrough in Silicon Photonics Technology in Telecommunications, Biosensing, and Gas Sensing. MICROMACHINES 2023; 14:1637. [PMID: 37630173 PMCID: PMC10456798 DOI: 10.3390/mi14081637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 08/17/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023]
Abstract
Silicon photonics has been an area of active research and development. Researchers have been working on enhancing the integration density and intricacy of silicon photonic circuits. This involves the development of advanced fabrication techniques and novel designs to enable more functionalities on a single chip, leading to higher performance and more efficient systems. In this review, we aim to provide a brief overview of the recent advancements in silicon photonic devices employed for telecommunication and sensing (biosensing and gas sensing) applications.
Collapse
Affiliation(s)
| | - Muhammad A. Butt
- Institute of Microelectronics and Optoelectronics, Warsaw University of Technology, Koszykowa 75, 00-662 Warszawa, Poland
| | | |
Collapse
|
3
|
Li K, Cao X, Wan Y, Wu G, Wang J. Fundamental analyses of fabrication-tolerant high-performance silicon mode (de)multiplexer. OPTICS EXPRESS 2022; 30:22649-22660. [PMID: 36224957 DOI: 10.1364/oe.457781] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 05/23/2022] [Indexed: 06/16/2023]
Abstract
Mode-division multiplexing (MDM) has been extensively exploited to expand the capacity of chip-scale optical interconnects, whereas high-volume manufacturing of on-chip mode (de)multiplexers is still full of challenges. In this paper, we analyze the fabrication errors (sidewall, width, height) of silicon mode (de)multiplexer and present two cases of fabrication-tolerant high-performance silicon mode (de)multiplexer. The presented mode (de)multiplexer could eliminate the mode mismatch and mode hybridization caused by the fabrication errors. When sidewall errors are 0°, 5°, width errors are 0, ± 20, ± 30 nm, and height errors are 0, ± 10 nm, the designed fabrication-tolerant high-performance silicon mode (de)multiplexer can achieve low excess loss less than 2.5 dB and low inter-mode crosstalk less than -15 dB over a broad bandwidth from 1500 to 1600 nm. The obtained results provide an important guideline for designing fabrication-tolerant photonic integrated circuits on silicon platform, which could be applied to the prospective high-volume manufacturing and large-scale integration.
Collapse
|
4
|
Minz M, Sonkar RK. Design of a grating-assisted silicon hybrid mode-, polarization-, and wavelength-division (De)multiplexer for on-chip optical interconnects. APPLIED OPTICS 2022; 61:3096-3100. [PMID: 35471284 DOI: 10.1364/ao.452497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
This paper presents a 12-channel hybrid mode-, polarization-, and wavelength-division (de)multiplexer. The proposed device is designed on a silicon-on-insulator platform. The device structure constitutes three coupling sections with a bus waveguide at the middle and two single-mode waveguides on each side. The periodic grating structures are present in between the waveguides for contra-directional coupling of the three TE modes and three TM modes of the bus waveguide to respective fundamental modes of the single-mode waveguides at 1550 and 1560 nm. The device is simulated using the 3D finite-difference time-domain technique, and the resulting insertion loss, cross talk, and return loss are <1.56dB, <-21.74dB, and >12.22dB, respectively. Moreover, the period of the grating structures is varied to perform the fabrication tolerance study.
Collapse
|
5
|
Onawa Y, Okayama H, Shimura D, Yaegashi H, Sasaki H, Kashima M. Multimode-based polarization independent WDM devices using different order modes for TE and TM polarizations. OPTICS EXPRESS 2020; 28:39227-39240. [PMID: 33379477 DOI: 10.1364/oe.412069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Multimode based polarization independent (PI) wavelength division multiplexing (WDM) devices are proposed and experimentally demonstrated. The key concept is to utilize two different order modes for the orthogonal polarizations, ith-order mode for TE and jth-order mode for TM (i ≠ j) polarization respectively to extend the flexibility for designing devices. PI coupler composed of a multimode directional coupler and mode converters is introduced as a basic device. Then, we apply PI coupler to Mach Zehnder interferometer (MZI) and Bragg grating bandpass filters. PI MZI is achieved by optimizing the combination of two phase shifters in the interferometer arms. PI bandpass uses 3dB-PI coupler and polarization rotate Bragg gratings that induce mode coupling between the polarizations. Each device showed good matching in the spectrum between TE and TM polarizations in term of operation wavelength. The proposed concept can be a promising approach to realize PI WDM functions without introducing polarization diversity scheme in which a polarization beam splitter, two devices designed for each polarization and a polarization beam combiner are required.
Collapse
|
6
|
He Y, Zhang Y, Wang H, Sun L, Su Y. Design and experimental demonstration of a silicon multi-dimensional (de)multiplexer for wavelength-, mode- and polarization-division (de)multiplexing. OPTICS LETTERS 2020; 45:2846-2849. [PMID: 32412483 DOI: 10.1364/ol.390015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 04/05/2020] [Indexed: 06/11/2023]
Abstract
Leveraging the physical dimensions of an optical carrier (e.g., wavelength, mode, or polarization) allows significant scaling of the transmission capacity for optical communications. Here we propose a scheme for implementing on-chip silicon (de)multiplexers with simultaneous wavelength-, mode-, and polarization-division (de)multiplexing capability. The device is constructed by using cascaded subwavelength grating (SWG)-based contra-directional couplers. To verify the feasibility of the proposed structure, we perform a proof-of-concept experiment of an 8-channel (de)multiplexer with two wavelengths, two modes, and two polarizations. The insertion losses are lower than 6.6 dB and the crosstalk values are below -18.7dB at around 1540 nm and 1550 nm for all the eight channels.
Collapse
|
7
|
Mehrabi K, Zarifkar A, Babaei M. Compact, high-performance, and fabrication friendly two-mode division multiplexer based on a silicon bent directional coupler. APPLIED OPTICS 2020; 59:3645-3651. [PMID: 32400480 DOI: 10.1364/ao.385585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 03/02/2020] [Indexed: 06/11/2023]
Abstract
In response to the increasing demands of the capacity enhancement of optical communication, a compact and high-performance silicon mode division multiplexer is proposed that multiplexes the fundamental and first-order transverse magnetic modes. The device structure is based on an asymmetric bent directional coupler with an ultrasmall coupling length of 3.67 µm. Utilizing single-layer silicon waveguides with the same heights allows the proposed device to be fabricated using a single-step CMOS-compatible fabrication process, which provides a cost-effective design in comparison with the previously reported structures. The three-dimensional finite-difference time-domain simulation results confirm that the device has a low loss of 0.87 dB, low crosstalk of ${-}{21.8}\;{\rm dB}$-21.8dB, and high mode conversion efficiency of 98.3% at the communication wavelength of 1.55 µm. Furthermore, the device shows a broad bandwidth of about 110 nm, completely covering the C and L bands with crosstalk less than ${-}{10}\;{\rm dB}$-10dB. Moreover, it is shown that the proposed mode (de)multiplexer is fabrication tolerant for the coupling gap variation of ${-}{40}\;{\rm nm} \lt \Delta {g} \lt {23}\;{\rm nm}$-40nm<Δg<23nm and the waveguide width variation of ${-}{25}\;{\rm nm} \lt \Delta {W} \lt {25}\;{\rm nm}$-25nm<ΔW<25nm for a low loss of ${ \lt }- {1.67}\;{\rm dB}$<-1.67dB and low crosstalk of ${ \lt }- {10}\;{\rm dB}$<-10dB.
Collapse
|
8
|
Liu L, Xu Y, Wen L, Dong Y, Zhang B, Ni Y. Design of a compact silicon-based TM-polarized mode-order converter based on shallowly etched structures. APPLIED OPTICS 2019; 58:9075-9081. [PMID: 31873584 DOI: 10.1364/ao.58.009075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 10/22/2019] [Indexed: 06/10/2023]
Abstract
A mode-order converter is an indispensable component in some typical on-chip mode-division-multiplexing (MDM) systems. Here, we propose a compact and high-performance TM-polarized mode-order converter using shallowly etched structures on the silicon waveguide. This device consists of a rhombus etching part at the waveguide center and two same triangle etching parts on both sides of the waveguide along the propagation direction to achieve the mode conversion from the input ${{\rm TM}_0}$TM0 to the output ${{\rm TM}_2}$TM2 mode, where both the effective waveguide structure and the corresponding effective index distribution can be changed. By optimizing the dimensions of the rhombus and triangle etching parts as well as the relative position between them, we have realized the efficient ${{\rm TM}_0}$TM0 to ${{\rm TM}_2}$TM2 mode conversion in a conversion length of only 6 µm, which distinguishes from mainly reported TE-polarized mode-order converters, and the obtained mode conversion efficiency (CE), cross talk (CT), and insertion loss (IL) are $\sim{94}\% $∼94%, $ \lt - {15}\;{\rm dB}$<-15dB, and $\sim{0.5}\;{\rm dB}$∼0.5dB, respectively, at the wavelength of 1.55 µm. Meanwhile, the allowable bandwidth can be extended to 128 nm by keeping ${\rm CE} \gt {94}\% $CE>94%, where the mode CT and IL are $ \lt - {15}\;{\rm dB}$<-15dB and ${\rm IL} \lt {0.7}\;{\rm dB}$IL<0.7dB, respectively, in the same wavelength range. Also, the device fabrication processes and tolerance analyses have been done. We hope this device could be beneficial for the capacity improvement of the on-chip MDM systems.
Collapse
|
9
|
Xu H, Shi Y. Subwavelength-grating-assisted silicon polarization rotator covering all optical communication bands. OPTICS EXPRESS 2019; 27:5588-5597. [PMID: 30876158 DOI: 10.1364/oe.27.005588] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 02/09/2019] [Indexed: 06/09/2023]
Abstract
We propose an ultra-broadband and ultra-compact polarization rotator (PR) structure on the silicon-on-insulator platform. The subwavelength gratings (SWGs) are introduced at the waveguide corner in order to excite the hybridized modes and realize the polarization rotation. The dispersion-engineered SWG can dramatically reduce the polarization conversion length deviation. High polarization extinction ratio > 20 dB and low excess loss < 1 dB can be achieved over 1.26-1.675 μm wavelength range, which covers O-, E-, S-, C-, L-, and U-bands. The total device size is as small as 4.8 × 0.34 μm2. To the best of our knowledge, the proposed structure is the first silicon PR that could cover all of the optical communication bands.
Collapse
|
10
|
Tan Y, Wu H, Wang S, Li C, Dai D. Silicon-based hybrid demultiplexer for wavelength- and mode-division multiplexing. OPTICS LETTERS 2018; 43:1962-1965. [PMID: 29714772 DOI: 10.1364/ol.43.001962] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 03/20/2018] [Indexed: 06/08/2023]
Abstract
A silicon-based hybrid demultiplexer for wavelength-division multiplexing (WDM) and mode-division multiplexing (MDM) is proposed and demonstrated by integrating an M-channel-mode demultiplexer and N-channel WDM filters based on microring resonators (MRRs) with box-like responses. For the mode demultiplexer, the 2k-th output port is connected with the (2k+1)-th output port through the bus waveguide for the k-th MRR array, so that each MRR-based optical filter works bi-directionally and provides two drop ports. As an example, a 32-channel hybrid MDM-WDM demultiplexer is realized by integrating a 4-channel mode demultiplexer based on dual-core adiabatic tapers and two bi-directional MRR-based WDM filters with eight wavelength-channels. For the fabricated hybrid demultiplexer, the excess loss is 0.5-5 dB, the intermode cross talk is -16.5 to -23.5 dB, and the cross talks between the adjacent and nonadjacent wavelength channels are about -25 dB and -35 dB, respectively.
Collapse
|
11
|
Zhang T, Ke X, Yin X, Chen L, Li X. Graphene-assisted ultra-compact polarization splitter and rotator with an extended bandwidth. Sci Rep 2017; 7:12169. [PMID: 28939811 PMCID: PMC5610311 DOI: 10.1038/s41598-017-12536-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 09/12/2017] [Indexed: 11/09/2022] Open
Abstract
The high refraction-index contrast between silicon and the surrounding cladding makes silicon-on-insulator devices highly polarization-dependent. However, it is greatly desirable for many applications to address the issue of polarization dependence in silicon photonics. Here, a novel ultra-compact polarization splitter and rotator (PSR), constructed with an asymmetrical directional coupler consisting of a rib silicon waveguide and a graphene-embedded rib silicon waveguide (GERSW), on a silicon-on-insulator platform is proposed and investigated. By taking advantage of the large modulation of the effective refractive index of the TE mode for the GERSW by tuning the chemical potential of graphene, the phase matching condition can be well satisfied over a wide spectral band. The presented result demonstrates that for a 7-layer-graphene-embedded PSR with a coupling length of 11.1 μm, a high TM-to-TE conversion efficiency (>−0.5 dB) can be achieved over a broad bandwidth from 1516 to 1602 nm.
Collapse
Affiliation(s)
- Tian Zhang
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.,State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts and Telecommunications, Beijing, 100876, China
| | - Xianmin Ke
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Xiang Yin
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Lin Chen
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China.
| | - Xun Li
- Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, 430074, China
| |
Collapse
|
12
|
Wang Y, Gao S, Wang K, Skafidas E. Ultra-broadband and low-loss 3 dB optical power splitter based on adiabatic tapered silicon waveguides. OPTICS LETTERS 2016; 41:2053-2056. [PMID: 27128072 DOI: 10.1364/ol.41.002053] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A broadband, low-loss and polarization-insensitive 3 dB optical power splitter based on adiabatic tapered silicon waveguides is proposed and investigated. 3D-FDTD simulation results show that the splitter achieves an output transmission efficiency of nearly 50% over an ultra-broad wavelength range from 1200 to 1700 nm. The device is fabricated, and experimental results show that the splitter exhibits a low excess loss of <0.19 dB for the TE polarization and <0.14 dB for the TM polarization over the entire measured wavelength range from 1530 to 1600 nm, while having an adiabatic taper length of only 5 μm. In addition, the measured power uniformity of the cascaded 1×8 splitter is only 0.47 dB, and 0.17 dB for the TE and TM polarizations, respectively. With the advantages of low loss, broad bandwidth, and compact size, the proposed splitter is a promising element for large-scale silicon integrated photonic circuits.
Collapse
|