Session Index

Terahertz (THz) plasmonic metamaterials based on metal-wire-woven hole arrays (MWW-HAs) are investigated in this study for the 0.1–2 THz transmittance. Different orders of the power depletion were presented in experiments but only that at the lowest frequency, corresponding to the first order one, can perform the strongest reflection due to the plasmonic reflection character. The bending angle of MWW-HA was found as the key parameter to achieve specular reflection for a long-distance transmission when the surface conductivity and optical path length of metal woven wires were modified to observe the transmittance variation of the first-order power depletion of MWW-HA.

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We discuss the formation of relativistic inverse Doppler effects inside Cherenkov radiation cone in positive index of refraction. The outcome can be distinguished two types: superluminal normal and inverse Doppler frequency shifts. The form (latter) exhibits the negative received frequency and positive (negative) frequency shift. In order to understand the behind mechanism, we also consider one emitting dipole source with periodic time sequences to draw the corresponding wave fronts in observed spaces, indicating the counter-inuitive results of the later signal received first.

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In this paper, optical frequency comb generation utilizing nonlinear dynamics of the semiconductor lasers subject to both optical injection and optoelectronic feedback are studied. Based on the regular pulsing states in the semiconductor laser under optoelectronic feedback, the optical frequency combs are generated. Furthermore, by applying an additional optically injection to the optical frequency comb generated, bandwidth enhancement of the optical frequency combs is found obviously in the optical spectra of the semiconductor lasers. Moreover, the detailed characteristics in different operational parameters are also discussed in this paper.

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The shift-or-shrink (SOS) algorithm was twice utilized for optimizing the structural parameters of the round-end cylindrical microlens, instead of applying it to very complicated formulae once. The optimal direct coupling efficiencies of single-mode fibers and optical channel waveguides, and their corresponding structural parameters, are presented in this paper.

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One of the intriguing optical waveguide phenomena that has been used in a wide range of applications is self-imaging. Here, we have carried out an experimental investigation of the self-imaging phenomena in the single-multi-single mode (SMS) fibre combination, which is additionally validated theoretically.

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We design a waveguide photodetector consisting of a germanium slab on a silicon-on-insulator substrate operated at a slow-light mode. By fine-tuning the structures of two-dimensional photonic crystal waveguide and coupler, the effective absorption coefficient of our device can be enhanced to 1.41 dB/µm at 1611 nm wavelength, which is about 1 order of magnitude improvement over the case of bulk Ge.

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This paper investigates the effects of using plated-through-hole (PTH) vias and
coaxial vias in differential mode for high-speed signal propagation. While PTH vias are
relatively cheaper to produce, they suffer from higher loss compared to coaxial vias. This paper
delves into the loss problem of using two single-ended signal vias versus one differential signal
via structure, and discusses it in depth.


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is paper is based on a one-dimensional phoxonic crystal waveguide, achieved by designing a periodic array of semicircular air holes on both sides of the waveguide. One type involves gradually varying the width of the waveguide, giving the structure phononic resonant cavity characteristics for sound waves and photonic waveguide characteristics for light waves. The other type involves using a gradient change in the lattice constant to confine the energy of both the light and sound wave resonant modes within the defect structure. We discuss the acoustic-optic coupling efficiency between the photonic and different phononic modes for both types of structures.

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Modulation format conversion from 8QAM to BPSK based on four-wave mixing using highly nonlinear fiber is proposed. Calculated BER performance and relationship between 8QAM and BPSK propagation length show that error-free conversion can be achieved.

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In this paper, we investigated the performance of the two most-established photodiodes as Terahertz (THz) emitters: Uni-Traveling-Carrier Photodiode (UTC-PD) and P-I-N Photodiode (PIN-PD). For comparison purpose, we transmitted several Quadrature Amplitude Modulation with Orthogonal Frequency Division Multiplexing (QAM-OFDM) signals of different bandwidth and modulation format, where the signals traveled through a 1-meter wireless link. At the receiver side, we analyzed the signal by an offline MATLAB program. The experimental results indicate that UTC-PD outperforms PIN-PD in the setup of our THz wireless communication system.

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In this study, we investigated the effect of angle misalignment on signal-to-noise ratio on a terahertz wireless communication network, and we proposed a formula to verify the data. The system is tested under several scenarios, we evaluated signal-to-noise ratio under different angel of misalignment. The signal-to-noise ratio are monitored to evaluate the performance of the terahertz wireless communication system. A formula is derived to explain the received result. The study provides a theoretical way to estimate the performance of communication system when misalignments exist.

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We have proposed a novel microwave photonic (MWP) circuit switch using the P1 nonlinear semiconductor lasers dynamics. Our system integrates multiple radio channels over fiber for wider bandwidth and flexibility. Channel selection can be optically adjusted by controlling the injection parameters. We demonstrate that our design can greatly enhance the input signal quality through the optical modulation depth improvement, with successful 1.25 Gbps ASK data transmissions in the experimental results. The proposed design demonstrates improved signal quality and offers potential applications for 6G SDN fronthaul networks.

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In this study, we present the evaluation of the thermal vacuum performance of home-made (2+1)×1 side-pumping combiners through completed thermal vacuum tests compliant with TRL-5 standards. These combiners are composed of radiation-hardened DCF and MMF fibers from iXblue and are designed for optical amplifier applications in the space environment. The results indicate that the combiners perform exceptionally well, handling a total power of 60W at 980nm. Throughout the 1000 hours vacuum test and 24 hours vacuum temperature cycling test, the insertion loss remained consistent with the original design level, measuring approximately -0.13dB, while the pump efficiency was around 97.48%.

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In silicon photonics, a light source with a stable wavelength is required. In this paper, we design and fabricate a four-channel coarse wavelength division multiplexing laser emission module with thermoelectric coolers (TECs). Setting the TEC temperature at 25℃, the characteristics of the output light remain stable while the laser diode current is from 0 mA to 120 mA. For the 1329-nm wavelength channel, the side mode suppression ratio is 47.3dB.

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