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Aiming to enhance the internal quantum efficiency (IQE) of AlGaN-based deep ultraviolet light-emitting diodes (DUV LEDs), the active region based on the V-shaped quantum well (QW) and the electron-blocking layer (EBL) structure are jointly optimized using intelligent algorithms in this work. This method focuses on maximizing the IQE of the DUV LEDs by optimizing the geometric and material parameters of multiple QWs (MQWs) and EBL. It is demonstrated that the DUV LED with an optimized structure exhibits smaller band edge tilt for improved wave function overlap in QWs and more effective carrier blocking for reduced electron overflow compared to that with a conventional structure. The results show that, by optimizing the active region and EBL structure using the proposed method, the IQE and maximum radiation intensity of the AlGaN-based DUV LED are enhanced by 38% and 41% at 200 A/cm2 injection current density, respectively. [ABSTRACT FROM AUTHOR]

Sketching on the Social Exchange Theory (SET), the present study aims to investigate the direct relationship between training and development, work environment, and job satisfaction with employee retention. The contingent role of transformational leadership was also analysed under the Situational Leadership Theory (SLT). Accordingly, we collected data from 287 employees of SMEs in northern China by employing a convenience sampling approach, exhibiting a response rate of 57.40 percent. The Partial Least Square-Structural Equation Modelling (PLS-SEM) analysis was then run to test the proposed hypotheses. The findings revealed a significant positive impact of training and development, work environment, and job satisfaction on employee retention. However, no moderating effect of transformational leadership was indicated on their direct relationship. This study has enriched the literature on employee retention and the leadership arena. To the best of the authors’ knowledge, there is no prior evidence concerning the study’s integrated relationship of the continuous variables. The implications and limitations were finally expressed at the end of this manuscript.

This study aimed to examine the integrated relationships of business ties, political ties, sustainable leadership, and frugal innovation. The correlation was assessed with the consideration of social network and situational leadership theories. Data was collected from 363 Small and Medium Enterprises (SMEs) employees in Pakistan with a response rate of 72.60%. Accordingly, the Partial Least Squares-Structural Equation Modeling (PLS-SEM) was employed to examine the validity of the proposed hypotheses. Empirical findings confirmed the significant impact of managerial and business ties on frugal innovation, strengthened by sustainable leadership. However, data analysis negated the positive impact of political ties on frugal innovation, which remains non-significant with the introduction of sustainable leadership among Pakistani SMEs. Hence, future studies are recommended to explore other conditional factors and mediating mechanisms in the relationship between managerial ties and frugal innovation. This idea can bring a deeper insight into the vital role of networking. To the best of the author’s knowledge, no prior study is available about the integrated relationships of managerial ties, frugal innovation, and sustainable leadership. This study enriches the literature in innovation management, especially concerning the social network and situational leadership model.

In this work, we report on the selective area growth (SAG) of InGaN multiple quantum well (MQW) structures to completely suppress the phenomenon of the Stokes shift in monolithically integrated photonic chips. The original green MQW region is designed as the integrated photodetector (PD), while the SAG blue MQW region acts as the integrated light-emitting diode (LED). The detection spectra of the PD can completely cover the emission spectra of the LED, greatly improving the on-chip optical connection by the complete suppression of the Stokes shift. Thus, the bottleneck of on-chip optical connection based on spectra-tail overlap in integrated photonic chips has been broken. Under the same operating current, the photocurrent of the SAG integrated PD reaches 11.8 μA, while the conventional chip achieves only 0.6 μA. By SAG method, the photo-to-dark current ratio of integrated PD exhibits about two orders of magnitude increase under 0 V bias. Undoubtedly, the SAG technology provides a strategy to further improve the on-chip optical signal transmission efficiency of the MQW structure integrated photonic chips. [ABSTRACT FROM AUTHOR]