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Single photon emitters, preferably working at room temperature, are crucial components of a diverse set of quantum technologies. Nanowire-supported quantum dots (NWQDs) of InGaN have emerged in the recent past as promising candidates of single photon emission (SPE) at visible wavelengths, though their efficient operation so far has been restricted to cryogenic temperatures. Here, we report the demonstration of visible-wavelength (λ = 561 nm) SPE at room temperature, from specially designed InGaN NWQDs, wherein the second-order correlation function at zero-delay is measured to be the lowest reported so far (g2 (0) = 0.11), for this system. Using a single-step molecular-beam-epitaxy-based fabrication technique, we realized InGaN NWQDs with both lateral and vertical dimensions scaled down to the Bohr-radius limit. This achievement is responsible not only for the efficient single photon emission at room temperature but also for the reduction of carrier lifetimes to the order of several hundreds of picoseconds. The latter has been made possible by the suppression of the built-in polarization field, which is attributed to the strong radial confinement obtained in the NWQDs fabricated by our method. These InGaN NWQDs are thus extremely promising for the development of visible-wavelength single photon sources, operating at room temperature and GHz repetition rates. [ABSTRACT FROM AUTHOR]

Three sets of InGaN/GaN nanowire (NW) heterostructures are grown on Si(111) substrates under different growth conditions. A quasi‐two‐dimensional p‐GaN layer is grown on top of those structures using the epitaxial lateral overgrowth (ELOG) technique. Finally, the light‐emitting diodes (LED) are fabricated using these hybrid nanostructures following standard fabrication techniques. Electroluminescence (EL) measurement confirmed the emission wavelengths of 530.0 nm (green), 608.3 nm (orange), and 632.5 nm (red). The knee voltages of the devices are estimated to be in the range of 2.18–2.89 V, with higher knee voltages for samples emitting lower wavelengths. Further analysis of forward bias electrical characteristics suggests the dominance of tunneling current and an increase in the defect density in the heterostructures emitting higher wavelengths. [ABSTRACT FROM AUTHOR]

Coronavirus disease-2019 (COVID-19) pandemic is raging all over the world. As we are delving more into management of COVID-19, certain new challenges are emerging. One of these is emergence or reactivation of viral infections belonging to Herpesviridae family, especially cytomegalovirus (CMV). Although we have come across the threat of fungal and resistant bacterial infections, experience regarding reactivation or coinfection with concomitant viral infections like CMV during the COVID pandemic is still limited. Whether CMV is a bystander or pathogen is difficult to say categorically and needs further research. In this case series, we intend to describe three patients of COVID-19 with CMV coinfections. To our knowledge, this is the first case series from India. [ABSTRACT FROM AUTHOR]

While analyzing current–voltage characteristics in the forward region of the MBE grown Al/Al0.3Ga0.7As/GaAs Schottky barrier diode (SBD) at a higher voltage it has been found out that for a range of voltage the current does not change exponentially, rather the current seems to be saturated. In this work, the cause of such a saturation is analyzed with the help of a two-diode model. Here another secondary diode is assumed to be formed due to improper ohmic contact. Possibilities of having this kind of unwanted saturation in devices with proper ohmic contacts have also been analyzed. [ABSTRACT FROM AUTHOR]