High-power VIPS-LD and SMF-LD module with fiber output power up to 110 mW

Abstract We demonstrated 22 W LD-pumped high-power continuous-wave (CW) deep red laser operations at 718.5 and 720.8 nm based on an a-cut Pr3+:YLF crystal. The output power of both polarized directions reached the watt-level without output power saturation. A single wavelength laser operated at 720.8 nm in the π-polarized direction was achieved, with a high output power of 4.5 W and high slope efficiency of approximately 41.5%. To the best of our knowledge, under LD-pumped conditions, the laser output power and slope efficiency are the highest at 721 nm. By using a compact optical glass plate as an intracavity etalon, we suppressed the π-polarized 720.8 nm laser emission. And σ-polarized single-wavelength laser emission at 718.5 nm was achieved, with a maximum output power of 1.45 W and a slope efficiency of approximately 17.8%. This is the first time that we have achieved the σ-polarized laser emission at 718.5 nm generated by Pr3+:YLF lasers.

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Review of the high-power vacuum tube microwave sources based on Cherenkov radiation

10.31219/osf.io/vdk43 ◽

2020 ◽

Author(s):

Weiye Xu

Keyword(s):

Output Power ◽

High Power ◽

Traveling Wave ◽

Cherenkov Radiation ◽

Continuous Wave ◽

Vacuum Tube ◽

Microwave Source ◽

Vacuum Tubes ◽

Traveling Wave Tubes ◽

Microwave Sources

Since the first vacuum tube (X-ray tube) was invented by Wilhelm Röntgen in Germany, after more than one hundred years of development, the average power density of the vacuum tube microwave source has reached the order of 108 [MW][GHz]2. In the high-power microwave field, the vacuum devices are still the mainstream microwave sources for applications such as scientific instruments, communications, radars, magnetic confinement fusion heating, microwave weapons, etc. The principles of microwave generation by vacuum tube microwave sources include Cherenkov or Smith-Purcell radiation, transition radiation, and Bremsstrahlung. In this paper, the vacuum tube microwave sources based on Cherenkov radiation were reviewed. Among them, the multi-wave Cherenkov generators can produce 15 GW output power in X-band. Cherenkov radiation vacuum tubes that can achieve continuous-wave operation include Traveling Wave Tubes and Magnetrons, with output power up to 1MW. Cherenkov radiation vacuum tubes that can generate frequencies of the order of 100 GHz and above include Traveling Wave Tubes, Backward Wave Oscillators, Magnetrons, Surface Wave Oscillators, Orotrons, etc.

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Design of W-Band GaN-on-Silicon Power Amplifier Using Low Impedance Lines

Applied Sciences ◽

10.3390/app11199017 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9017

Author(s):

Jinho Jeong ◽

Yeongmin Jang ◽

Jongyoun Kim ◽

Sosu Kim ◽

Wansik Kim

Keyword(s):

Power Density ◽

Output Power ◽

Power Amplifier ◽

High Power ◽

Common Source ◽

High Electron ◽

Large Signal ◽

Power Added Efficiency ◽

W Band ◽

Gan On Si

In this paper, a high-power amplifier integrated circuit (IC) in gallium-nitride (GaN) on silicon (Si) technology is presented at a W-band (75–110 GHz). In order to mitigate the losses caused by relatively high loss tangent of Si substrate compared to silicon carbide (SiC), low-impedance microstrip lines (20–30 Ω) are adopted in the impedance matching networks. They allow for the impedance transformation between 50 Ω and very low impedances of the wide-gate transistors used for high power generation. Each stage is matched to produce enough power to drive the next stage. A Lange coupler is employed to combine two three-stage common source amplifiers, providing high output power and good input/output return loss. The designed power amplifier IC was fabricated in the commercially available 60 nm GaN-on-Si high electron mobility transistor (HEMT) foundry. From on-wafer probe measurements, it exhibits the output power higher than 26.5 dBm and power added efficiency (PAE) higher than 8.5% from 88 to 93 GHz with a large-signal gain > 10.5 dB. Peak output power is measured to be 28.9 dBm with a PAE of 13.3% and a gain of 9.9 dB at 90 GHz, which corresponds to the power density of 1.94 W/mm. To the best of the authors’ knowledge, this result belongs to the highest output power and power density among the reported power amplifier ICs in GaN-on-Si HEMT technologies operating at the W-band.

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High-power long-wave infrared laser based on polarization beam coupling technique

High Power Laser Science and Engineering ◽

10.1017/hpl.2020.10 ◽

2020 ◽

Vol 8 ◽

Author(s):

Yingjie Shen ◽

Chuanpeng Qian ◽

Xiaoming Duan ◽

Ruijun Lan

Keyword(s):

Output Power ◽

High Power ◽

Beam Quality ◽

Maximum Output Power ◽

Infrared Laser ◽

Maximum Output ◽

Coupling Technique ◽

Long Wave ◽

Beam Coupling ◽

Long Wave Infrared

We demonstrated a high-power long-wave infrared laser based on a polarization beam coupling technique. An average output power at $8.3~\unicode[STIX]{x03BC}\text{m}$ of 7.0 W was achieved at a maximum available pump power of 107.6 W, corresponding to an optical-to-optical conversion of 6.5%. The coupling efficiency of the polarization coupling system was calculated to be approximately 97.2%. With idler single resonance operation, a good beam quality factor of ${\sim}1.8$ combined with an output wavelength of $8.3~\unicode[STIX]{x03BC}\text{m}$ was obtained at the maximum output power.

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A 4.2-to-5.4 GHz stacked GaAs HBT power amplifier for C-band applications

Circuit World ◽

10.1108/cw-05-2019-0046 ◽

2020 ◽

Vol 46 (4) ◽

pp. 243-248

Author(s):

Min Liu ◽

Panpan Xu ◽

Jincan Zhang ◽

Bo Liu ◽

Liwen Zhang

Keyword(s):

Output Power ◽

Power Amplifier ◽

High Power ◽

High Efficiency ◽

Common Source ◽

Power Performance ◽

Matching Network ◽

Content Type ◽

Power Added Efficiency ◽

Saturated Output Power

Purpose Power amplifiers (PAs) play an important role in wireless communications because they dominate system performance. High-linearity broadband PAs are of great value for potential use in multi-band system implementation. The purpose of this paper is to present a cascode power amplifier architecture to achieve high power and high efficiency requirements for 4.2∼5.4 GHz applications. Design/methodology/approach A common emitter (CE) configuration with a stacked common base configuration of heterojunction bipolar transistor (HBT) is used to achieve high power. T-type matching network is used as input matching network. To increase the bandwidth, the output matching networks are implemented using the two L-networks. Findings By using the proposed method, the stacked PA demonstrates a maximum saturated output power of 26.2 dBm, a compact chip size of 1.17 × 0.59 mm2 and a maximum power-added efficiency of 46.3 per cent. The PA shows a wideband small signal gain with less than 3 dB variation over working frequency. The saturated output power of the proposed PA is higher than 25 dBm between 4.2 and 5.4 GHz. Originality/value The technology adopted for the design of the 4.2-to-5.4 GHz stacked PA is the 2-µm gallium arsenide HBT process. Based on the proposed method, a better power performance of 3 dB improvement can be achieved as compared with the conventional CE or common-source amplifier because of high output stacking impedance.

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