Article
Optics
Hongzhi Yang, Yuan Gao, Lei Wang, Sijia Wang, Peng Qing, Yefei Mao, Ziyue Zhang, Ju Zhou
Summary: This paper presents a novel method for measuring the frequency response of electro-optic phase modulators by analyzing the instantaneous frequency of a sinusoidal frequency-modulated signal. The experimental results are supported by a simple theoretical model and the accuracy of half-wave voltage measurement is discussed.
Article
Engineering, Electrical & Electronic
Hongqiang Li, Wentao Meng, Zhilin Lin, Feng Ren, Lu Cao, Liying Chen, Lizhen Zhang, Cheng Zhang, Zhiyue Zhu, Yingjie Wang, Enbang Li, Joan Daniel Prades
Summary: A hybrid silicon/polymer asymmetric Mach-Zehnder (MZ) electro-optic modulator is proposed for ECG weak signal modulation with low half-wave voltages and low loss. The modulator operates in the 1550 nm band and consists of two 3 dB multimode interference couplers, a bent waveguide, a modulation waveguide, and a phase shifter. Simulation results demonstrate a low loss of -3.4 dB and a low half-wave voltage amplitude of 3.0 V for the modulator.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Optics
Stefano Grillanda, Ting-Chen Hu, David Neilson, Mark Earnshaw
Summary: A novel design for SNEAMs is proposed which significantly reduces required voltage and increases extinction ratio by optimizing structure and reflectivity, outperforming conventional devices.
Article
Engineering, Electrical & Electronic
Stephen R. Anderson, Amir Begovic, Hao Jiang, Z. Rena Huang
Summary: This work presents two slow-light enhanced silicon optical modulators with electro-optic phase shifter lengths of 500 μm and 150 μm, fabricated using the AIM Photonics foundry. Tunable power splitters result in a threefold increase in the extinction ratio. Operating at 10 Gbps, an eye diagram was achieved with a very low signal voltage of V-pp = 500mV. The energy per bit is 57.5 fJ/bit and 45 fJ/bit for the 500 μm and 150 μm modulators, respectively. The devices' nonlinearity was measured, yielding a spur-free dynamic range of 113.2 dB/Hz(2)/(3). The 150 μm length MZM is one of the smallest optical modulators using Bragg gratings for slow light ever reported, with an estimated modulation efficiency of 0.33 V·cm.
IEEE PHOTONICS TECHNOLOGY LETTERS
(2023)
Article
Instruments & Instrumentation
Junfeng Zhu, Xinhai Zou, Ying Xu, Yutong He, Yali Zhang, Zhiyao Zhang, Shangjian Zhang, Yong Liu
Summary: A bias-independent inter-modulation method is proposed to measure low-frequency modulation and bias half-wave voltages of Mach-Zehnder modulators (MZMs). The method utilizes simultaneous sinusoidal modulation on the modulation and bias ports of the MZM, generating inter-modulation products that allow for the extraction of modulation depth and half-wave voltage. The method is unaffected by bias voltages and enables low swing voltage measurements. Experimental results demonstrate its simplicity, high accuracy, and wide frequency range (1 Hz to 1 MHz).
Article
Optics
Marco Eppenberger, Andreas Messner, Bertold Ian Bitachon, Wolfgang Heni, Tobias Blatter, Patrick Habegger, Marcel Destraz, Eva De Leo, Norbert Meier, Nino Del Medico, Claudia Hoessbacher, Benedikt Baeuerle, Juerg Leuthold
Summary: We demonstrate plasmonic micro-racetrack modulators for high-speed intensity-modulated transmission. These modulators offer wide bandwidth, improved temperature stability, and no self-heating effects. They can encode electrical data onto wavelength-multiplexed optical carriers.
Article
Engineering, Electrical & Electronic
Youngkwan Jo, Christian Mai, Stefan Lischke, Lars Zimmermann, Woo-Young Choi
Summary: The modulation linearity of Si ring modulators (RMs) was investigated using numerical simulation and experimental verification based on coupled-mode theory. The numerical values of key parameters were experimentally extracted and the simulation and measurement results showed good agreement. The study characterized the influence of input optical wavelength and power on the Si RM linearity.
JOURNAL OF LIGHTWAVE TECHNOLOGY
(2021)
Article
Engineering, Electrical & Electronic
Fernando Acosta-Cambranis, Jordi Zaragoza, Luis Romeral, Nestor Berbel
Summary: This article proposes a new modulation strategy for a five-phase high-frequency voltage source inverter based on sigma-delta modulators. The strategy achieves the same switching states as the traditional large-medium-large-medium space vector modulation using sigma-delta modulation, which operates efficiently at high switching frequencies using wide-bandgap devices. The proposed modulation techniques minimize switching losses, mitigate low-order harmonics, decrease the amplitude of high-frequency harmonics, and reduce common-mode voltage dv/dt transitions.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Multidisciplinary Sciences
Evgeniy S. Lotkov, Aleksandr S. Baburin, Ilya A. Ryzhikov, Olga S. Sorokina, Anton I. Ivanov, Alexander Zverev, Vitaly V. Ryzhkov, Igor Bykov, Alexander Baryshev, Yuri Panfilov, Ilya A. Rodionov
Summary: This paper investigates the optimization of Indium Tin Oxide (ITO) thin films for integrated optical modulators. The authors demonstrate the fabrication of ITO films with high extinction ratio and low insertion loss using e-beam evaporation technology. Different crystalline structures of ITO films are studied, and the mechanism of oxygen migration in film crystallization is analyzed. Experimental results show the potential of ITO films for creating electro-optical modulators with sub-dB losses.
SCIENTIFIC REPORTS
(2022)
Article
Multidisciplinary Sciences
Purushotham Selvakumar, Ana I. Fernandez-Marino, Nandish Khanra, Changhao He, Alice J. Paquette, Bing Wang, Ruiqi Huang, Vaughn V. Smider, William J. Rice, Kenton J. Swartz, Joel R. Meyerson
Summary: This study reports the structures of the Kv1.3 potassium channel and its role in immune modulation. By examining the interaction of nanobody and antibody-toxin fusion with the Kv1.3 channel, two distinct mechanisms to inhibit Kv1.3 channel activity were identified.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Dun Mao, Chen Cheng, Feifan Wang, Yahui Xiao, Tiantian Li, Lorry Chang, Anishkumar Soman, Thomas Kananen, Xian Zhang, Michael Krainak, Po Dong, Tingyi Gu
Summary: Graphene's atomic layer thin geometry and semi-metallic band diagram can enhance the performance of integrated photonic devices. By utilizing its semiconductor-like behavior and low loss properties, graphene can function as an active layer for electro-optic modulation with ultrafast speeds and energy efficiency. Hybrid device architectures, such as directly contacted graphene-silicon heterojunctions and graphene integrated lithium niobite modulators, demonstrate potential for high-speed modulation and improved coupling coefficient between optical and electric fields.
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
(2021)
Article
Immunology
Steven C. Mitini-Nkhoma, Narmada Fernando, G. K. D. Ishaka, Shiroma M. Handunnetti, Sisira L. Pathirana
Summary: Ion transport modulators are commonly used to treat noncommunicable diseases, and their immunomodulatory properties are still not completely understood. Thirteen FDA-approved ion transport modulators were tested for their effects on immune cells, showing both inhibitory and enhancing effects on nitric oxide production, cytokine expression, and superoxide production. This suggests that ion pumps and channels could be target for more selective immunomodulatory agents.
JOURNAL OF IMMUNOLOGY RESEARCH
(2021)
Review
Optics
Mian Zhang, Cheng Wang, Prashanta Kharel, Di Zhu, Marko Loncar
Summary: Thin-film lithium niobate has emerged as a strong contender for next-generation electro-optic modulators due to its high efficiency, performance stability, and scalability.
Article
Physics, Applied
Jie Zhang, Adam Charnas, Zehao Lin, Dongqi Zheng, Zhuocheng Zhang, Pai-Ying Liao, Dmitry Zemlyanov, Peide D. Ye
Summary: This Letter reports the improvement of electrical performance in indium oxide thin film transistors through a low-temperature CF4/N2O plasma treatment. The study finds that fluorination via CF4/N2O plasma effectively reduces excessive electrons in the In2O3 channel, resulting in improved electrical properties such as higher mobility, more positive threshold voltage, higher on/off current ratio, smaller subthreshold swing, and increased stability to gate biases. X-ray photoelectron spectroscopy confirms the fluorine incorporation and its role in enhancing TFT performance.
APPLIED PHYSICS LETTERS
(2022)
Article
Engineering, Electrical & Electronic
Oscar Pereira-Rial, Alessandro Cabrini, Guido Torelli, Paula Lopez, Juan M. Carrillo
Summary: This paper presents a subthreshold input voltage charge pump based on the cross-coupled voltage doubler and boosted gate voltages for the transfer switches. A novel inverter architecture called negative low-state voltage inverter is proposed to generate clock signals for switching transistors and improve their drive capability. Experimental characterization of silicon prototypes in 180 nm CMOS technology demonstrates that the proposed scheme can pump charge from an input voltage as low as 110 mV, with a peak efficiency above 70% for input voltages between 180 mV and 400 mV and input power levels ranging from 45 nW to 25 mu W, suitable for miniaturized transducers on chip.
IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS
(2023)
