We demonstrate an approach to actively stabilize the beam profile of a fiber amplifier above the mode instability threshold. Both the beam quality and the pointing stability are significantly increased at power levels of up to three times the mode instabilities threshold. The physical working principle is discussed at the light of the recently published theoretical explanations of mode instabilities.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1364/OE.21.017285 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Catatonia is one of the most severe psychiatric syndromes, and clinical symptoms and etiology are very heterogeneous. When accompanied by autonomic instability and hyperthermia it’s termed malignant catatonia, which left untreated is associated with significant morbidity and mortality. First-line treatment is high dose benzodiazepines, followed by electroconvulsive therapy (ECT), in case of non-response.
View Article and Find Full Text PDFSeq2Seq-based GRU autoencoder for anomaly detection and failure identification in coal mining hydraulic support systems.
Sci Rep
January 2025
School of Mines, China University of Mining and Technology, Xuzhou, China.
In coal mining operations, the stable operation of hydraulic supports is crucial for ensuring mine safety. However, the nonlinear, non-stationary characteristics and noise interference in hydraulic support pressure data pose significant challenges for anomaly detection and fault diagnosis. This study proposes an anomaly detection and failure identification method based on Gated Recurrent Unit Autoencoder (GRU-AE), aimed at achieving anomaly detection in hydraulic support pressure data and equipment failure early warning.
View Article and Find Full Text PDFAnalysis on characteristics and mechanism for rock fracture in deep rock with cracks under dynamic-static coupling effect.
Sci Rep
December 2024
School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001, Anhui, China.
The mechanical behavior and fracture mechanisms of deep fractured rocks under explosive dynamic loads are critical for understanding rock instability in engineering applications such as blasting operations. This study aims to investigate how the presence of pre-existing cracks and different stress states affect the mechanical properties and fracture patterns of rock-like specimens under dynamic loading conditions. We utilized a Split Hopkinson Pressure Bar (SHPB) with an active confining pressure loading device to conduct impact compression tests on rock-like specimens containing pre-existing cracks.
View Article and Find Full Text PDFTheoretical analysis of additional surrounding rock pressure in shallow buried bias tunnel.
Sci Rep
December 2024
China Construction Eighth Engineering Division Rail Transit Construction Co., Ltd, Nanjing, 210018, Jiangsu, China.
The existing calculation method for the surrounding rock pressure of shallow buried bias tunnel fails to account for the impact of the progressive failure characteristics of the surrounding rock and slope creep, thereby neglecting the additional pressure arising from slope creep. Therefore, the progressive instability failure mode of the surrounding rock of shallow buried bias tunnel was obtained by numerical simulation. Based on this, the theoretical analysis model of the additional pressure of shallow buried bias tunnel was established, and the calculation formula of the additional pressure was derived.
View Article and Find Full Text PDFTransverse mode instability (TMI) significantly limits the power scaling of ytterbium-doped fiber lasers. In this Letter, what we believe to be a novel TMI mitigation strategy is proposed and demonstrated in a bidirectional output fiber laser. On the basis of the continuous wave (CW) pump, integrating a quasi-continuous wave (QCW) pump can effectively improve the TMI threshold of the system.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!