Truong Cao Dung - Academia.edu (original) (raw)

Uploads

Papers by Truong Cao Dung

Journal of Science and Technology Issue on Information and Communications Technology, Jun 29, 2021

<jats:p>This paper presents a numerical simulation investigation on the bit error rate in a... more <jats:p>This paper presents a numerical simulation investigation on the bit error rate in a chaotic-secured fiber channel and a conventional fiber channel when propagating independently. The investigated communication system uses the pulse-amplitude modulation scheme (4-PAM) at the bit rate of 10 Gbps, the fiber length of 100 km, and the operation wavelength of 1550 nm. Our simulation results demonstrate both chaotic and non-chaotic transmission channels can well operate with the bit rate up to 20 Gbps with the BER smaller than 10-5 if dispersion and fiber loss issues are appropriately compensated without needing forwarderror-correction, showing high potential in physically secured optical fiber communication systems.</jats:p>

Optics & Laser Technology, 2021

Abstract In mode-division multiplexing (MDM) networks, converting modes back and forth between a ... more Abstract In mode-division multiplexing (MDM) networks, converting modes back and forth between a higher-order mode and a lower-order mode plays a vital role in improving network capacity and flexibility. This paper presents a spatial optical mode conversion supporting three modes based on two Ψ -junction couplers and two multi-mode interference couplers (MMIs). The proposed device can arbitrarily convert a TEi mode to a TEj mode (where i, j = 0, 1, 2) by setting three phase-shifters at 0 or 180 degrees, which are introduced at the Ψ -junction and MMI couplers. Through numerical simulations using the spatial three-dimensions beam propagation method (3D-BPM), the mode converter shows a high conversion efficiency with the insertion loss smaller than 0.2 dB and the crosstalk below −20 dB at the center wavelength of 1.55 μm. The device works effectively in C band, partially in S and L bands within a wideband up to 80 nm. We believe that the proposed device would be a potential platform for applications in MDM networks and photonic integrated circuit systems.

IEEE Photonics Journal, 2021

2019 6th NAFOSTED Conference on Information and Computer Science (NICS), 2019

In this paper, we introduce a structure can generate simultaneously three lowest optical modes TE... more In this paper, we introduce a structure can generate simultaneously three lowest optical modes TE0, TE1 and TE2 based on SOI platform. This device is built on two tridents and one Multimode interference (MMI) couplers. It is designed using 3D beam propagation method (3D-BPM) combined with effective index method (EIM). The simulation results show that the proposed device can operate in a wide wavelength range up to 140nm covering whole C and almost of L and S bands with low insertion loss, about -0.23 dB at the central wavelength of 1550 nm. Manufacturing tolerances of the device is rather large. In addition, the small footprint (5 µm×506 µm) makes the device not only compatible with the current CMOS manufacturing technology but also suitable with high bitrate applications of photonic integrated circuits inside MDM-WDM systems.

The Modified Discrete Consine Transform (MDCT) have found applications in digital signal, image a... more The Modified Discrete Consine Transform (MDCT) have found applications in digital signal, image and video processing and particularly in transform coding systerm for data compression and decompression. Multimode interference (MMI) in optical silicon on insulator (SOI) waveguides is attractive for realizing all-optical MDCT transforms as they have the advantages of low loss, ultra-compact size and excellent fabrication tolerances. In this paper, for the first time, a novel approach to realize all-opptical MDCT based on multimode interference structures on silicon on insulator platform is proposed. Base on the transfer matrix method, the analytical expressions describing the characteristics of the MMI structures are derived. Designs of the proposed devices are then verified and optimized using 2D and 3D BPM (Beam propagation method( simulations.

Journal of Science and Technology: Issue on Information and Communications Technology, 2021

This paper proposes a new design of two-mode three-port optical mode router for mode division mul... more This paper proposes a new design of two-mode three-port optical mode router for mode division multiplexing systems. The device consists of a Mach-Zehnder interferometer (MZI) and a multimode interferometer (MMI), which utilizes silicon material for photonic integrated circuits (PIC). By setting appropriate values for the two butterfly-shaped phase shifters (PSs) at MZI and MMI, the input mode, either transverse electric (TE) modes TE0 or TE1, can be routed to the desired output among the three output ports. The device is designed and optimized via three-dimensional beam propagation method (3D BPM). The proposed device achieves very low insertion loss and small cross-talk, which are less than 0.4 dB and -24.5 dB, respectively, over the whole C band.

EAI Endorsed Transactions on Industrial Networks and Intelligent Systems

IEEE Journal of Selected Topics in Quantum Electronics

Journal of Science and Technology Issue on Information and Communications Technology, Jun 29, 2021

<jats:p>This paper presents a numerical simulation investigation on the bit error rate in a... more <jats:p>This paper presents a numerical simulation investigation on the bit error rate in a chaotic-secured fiber channel and a conventional fiber channel when propagating independently. The investigated communication system uses the pulse-amplitude modulation scheme (4-PAM) at the bit rate of 10 Gbps, the fiber length of 100 km, and the operation wavelength of 1550 nm. Our simulation results demonstrate both chaotic and non-chaotic transmission channels can well operate with the bit rate up to 20 Gbps with the BER smaller than 10-5 if dispersion and fiber loss issues are appropriately compensated without needing forwarderror-correction, showing high potential in physically secured optical fiber communication systems.</jats:p>

Optics & Laser Technology, 2021

Abstract In mode-division multiplexing (MDM) networks, converting modes back and forth between a ... more Abstract In mode-division multiplexing (MDM) networks, converting modes back and forth between a higher-order mode and a lower-order mode plays a vital role in improving network capacity and flexibility. This paper presents a spatial optical mode conversion supporting three modes based on two Ψ -junction couplers and two multi-mode interference couplers (MMIs). The proposed device can arbitrarily convert a TEi mode to a TEj mode (where i, j = 0, 1, 2) by setting three phase-shifters at 0 or 180 degrees, which are introduced at the Ψ -junction and MMI couplers. Through numerical simulations using the spatial three-dimensions beam propagation method (3D-BPM), the mode converter shows a high conversion efficiency with the insertion loss smaller than 0.2 dB and the crosstalk below −20 dB at the center wavelength of 1.55 μm. The device works effectively in C band, partially in S and L bands within a wideband up to 80 nm. We believe that the proposed device would be a potential platform for applications in MDM networks and photonic integrated circuit systems.

IEEE Photonics Journal, 2021

2019 6th NAFOSTED Conference on Information and Computer Science (NICS), 2019

In this paper, we introduce a structure can generate simultaneously three lowest optical modes TE... more In this paper, we introduce a structure can generate simultaneously three lowest optical modes TE0, TE1 and TE2 based on SOI platform. This device is built on two tridents and one Multimode interference (MMI) couplers. It is designed using 3D beam propagation method (3D-BPM) combined with effective index method (EIM). The simulation results show that the proposed device can operate in a wide wavelength range up to 140nm covering whole C and almost of L and S bands with low insertion loss, about -0.23 dB at the central wavelength of 1550 nm. Manufacturing tolerances of the device is rather large. In addition, the small footprint (5 µm×506 µm) makes the device not only compatible with the current CMOS manufacturing technology but also suitable with high bitrate applications of photonic integrated circuits inside MDM-WDM systems.

The Modified Discrete Consine Transform (MDCT) have found applications in digital signal, image a... more The Modified Discrete Consine Transform (MDCT) have found applications in digital signal, image and video processing and particularly in transform coding systerm for data compression and decompression. Multimode interference (MMI) in optical silicon on insulator (SOI) waveguides is attractive for realizing all-optical MDCT transforms as they have the advantages of low loss, ultra-compact size and excellent fabrication tolerances. In this paper, for the first time, a novel approach to realize all-opptical MDCT based on multimode interference structures on silicon on insulator platform is proposed. Base on the transfer matrix method, the analytical expressions describing the characteristics of the MMI structures are derived. Designs of the proposed devices are then verified and optimized using 2D and 3D BPM (Beam propagation method( simulations.

Journal of Science and Technology: Issue on Information and Communications Technology, 2021

This paper proposes a new design of two-mode three-port optical mode router for mode division mul... more This paper proposes a new design of two-mode three-port optical mode router for mode division multiplexing systems. The device consists of a Mach-Zehnder interferometer (MZI) and a multimode interferometer (MMI), which utilizes silicon material for photonic integrated circuits (PIC). By setting appropriate values for the two butterfly-shaped phase shifters (PSs) at MZI and MMI, the input mode, either transverse electric (TE) modes TE0 or TE1, can be routed to the desired output among the three output ports. The device is designed and optimized via three-dimensional beam propagation method (3D BPM). The proposed device achieves very low insertion loss and small cross-talk, which are less than 0.4 dB and -24.5 dB, respectively, over the whole C band.

EAI Endorsed Transactions on Industrial Networks and Intelligent Systems

IEEE Journal of Selected Topics in Quantum Electronics