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GaN based Photonic Integrated Circuits (PICs) have now become a global contender for their wide range of applications owing their physical characteristics. The GaN material system acts as a promising platform; compatible with silicon and sapphire substrates. Both the carrier transport and carrier removal techniques are vital to develop the efficient platform for the integration of photonic circuits. We demonstrate the carrier removal mechanism in silicon (Si) doped GaN (0001) epitaxially grown on c-plane sapphire wafer using ion engineering of the devices. Ion-engineered regions within the active layers of the device are modelled, fabricated and characterized to assess the isolation created. Helium and Carbon ions with pre-designed doses and energies are used to irradiate the device structures. We have modelled and fabricated ion-engineered regions within the active layers and studied the carrier transport properties on said regions to isolate that particular part with either of active photonic components placed at the common platform. After ion irradiation, detailed analysis in terms of electric field dependent current characteristics, sheet resistance, carrier mobilities, activation energies, dark and photo currents under zero (ground) and multiple biases are examined to see the extent of charge leakage and to map the charge behavior under nominal operation. Device characteristics under wide regime of annealing temperatures ranging from 300°C to 1000°C are mapped to evaluate the thermal stability of implant driven isolated regions. Activation energies of implanted and parent regions has also been studied. The dark and photon driven electric currents at ground and under biased have been measured to investigate the photo-induced transport phenomenon.

The interplay between two key design aspects of Narrowband-IoT (NB-IoT) leads to a problematic scenario. First aspect is the excessive repetition of channels to achieve extended coverage, while second aspect is the absence of physical layer Scheduling Request (SR) mechanism which alternatively is done through Connected Mode Random Access Procedure (CRP). This problematic scenario remained unidentified so far and occurs frequently in real field deployments leading to significant wastage of radio resources. The underlying cause behind this issue can be attributed to a shortcoming in the present-day NB-IoT radio resource scheduler (residing in eNB). NB-IoT scheduler, in the process of drawing basic concepts from its Long-Term Evolution (LTE) counterpart has overlooked the complication arising out of the above unique design aspects of NB-IoT. In this paper we propose a novel method that can completely prevent this problematic scenario. This method introduces a new scheduling concept – “CRP Initiation State Aware” scheduling, which is exemplary in the sense that it can be realized with extremely simple implementation at eNB, that is neither complex nor memory intensive. The benefit of this method in terms of radio resource savings is substantial in today’s Machine Type Communication (MTC) context and is expected to increase manifold as we move towards 5G Massive MTC (mMTC) requirements. We further propose an enhancement to the “CRP Initiation State aware” scheduling that considerably enhances the UE’ battery life along-with more savings in radio resources.

This chapter is an exploration of the concept and practice of humanism in the Muslim Middle East, from the seventh-century Prophetic dispensation to the present times. Humanism has often been described as the peculiar fruit of the European Renaissance. The chapter challenges this claim by investigating the incidence of humanism in the Middle East around a three-tiered axis. First, humanism as a focus on this-worldly rather than other-worldly matters is not only compatible with the “worldliness” of an Islamic ethos but was historically encouraged by it. Second, modernist reformers portray humanism as an earlier “modern” age in the history of the Middle East that they now seek to renew. Finally, inasmuch as humanism is a form of anthropocentrism, theological ideas like al-insān al-kāmil, the perfect man, allow for such humanism to be embedded within a broader Islamic theocentrism. The chapter concludes with possible humanistic futures in the Middle East.

Pakistan finds itself at a crossroads, struggling between legitimizing the identity of trans gender and non-conforming (TGNC) persons and the multivariate forces that hold back this progression. This can be observed when one seeks out census data on the khawajasira population – a respectful Urdu term for TGNC persons.1 Officially this number stands at 10,422,2 but various organizations advocating for TGNC rights state this number to be around 300,000 to 500,000.3 So while progressive changes, such as the Transgender Person (Protection of Rights) Act of 2018,4 have led to Pakistan recognizing khawajasira as a third gender, they are grossly underreported on the national census. This gives us an insight into the problems faced when it comes to their recognition into Pakistani society, often stemming from the stigma of their own social networks. This stigma illustrates the intersectional nexus of discrimination reflected in religion and politics, resulting in disapproval, marginalization, and social banishment.5 Religion is instrumentalized by predominantly religious and other non-state actors who condemn khawajsira identity and culture, which further propagates the status quo.6 As a result, much of Pakistan’s TGNC populations live on the margins of society, with an overwhelming majority experiencing institutionalized discrimination and physical attacks.5 The odds of subsequent engagement in high-risk behaviors such as survival sex, drug use, and even suicide increase dramatically.5 Due to this marginalization, TGNC persons defer their healthcare needs until absolutely necessary thus undermining their outcomes from illnesses that are otherwise preventable.7 Specific reasons include prejudice by healthcare professionals, inexperience with TGNC healthcare, and the lack of legislation protecting TGNC rights.

In the introduction to his Contribution to the Critique of Hegel's Philosophy of Right (1843), Karl Marx famously noted that the criticism of religion is the beginning of all criticism. For inasmuc...

We report the high thermoelectric performance of p-type polycrystalline SnSe obtained below the phase transition temperature by harnessing Pb doping and introducing Sn vacancies. The enhanced carrier concentration induced by Pb doping and introducing Sn vacancies contributes to enhancements of electrical conductivity and power factor of polycrystalline SnSe. We demonstrate that the lattice anharmonicity is strengthened by Pb substitution and Sn vacancies through forming weaker bonds. We find that Pb substitution introduces huge stress field in the interior of the SnSe grains. The thermal conductivity can be greatly reduced by lattice anharmonicity strengthening and applying huge stress field. The lattice thermal conductivity is reduced to as low as 0.18 W m–1 K–1 in the Sn0.92Pb0.03Se sample at 773 K. As a result, a remarkable high ZT of ∼1.4 was achieved at 773 K in the Sn0.93Pb0.02Se sample through lattice anharmonicity strengthening and strain engineering.

Conventional concentrators with inhomogeneous coating materials that fully enclose the destined region pose great challenges for fabrication. In this paper, we propose to design an EM concentrator with homogeneous materials. Distinguished from conventional ones, the elaborately designed EM concentrator features a concentrator region that is open to the outer-world, which is achieved with multi-folded transformation optics method by compressing and folding the coating materials to create window(s). Based on this concept, we also investigate open-rotator and open rotational-concentrator devices, which could simultaneously rotate and store the EM waves in the central destined region. Due to the open nature of our proposed designs, we believe they will find potential applications in remote controlling with impressive new functionalities.

At least since Charles Martel defeated a Moorish army near Tours in 732 and continuing through the first and second crusades, the Reconquista, and the various sieges of Vienna, Islam has been an in...

At least since Aristotle, the golden mean has enticed many a thinker as an attribute of beauty and of truth, as the middle path between excess and deficiency. In his Muslim Identities: An Introduct...