Bright and Dark Exciton Coherent Coupling and Hybridization Enabled by External Magnetic Fields.

Magnetic field- and polarization-dependent measurements on bright and dark excitons in monolayer WSe2 combined with time-dependent density functional theory calculations reveal intriguing phenomena. Magnetic fields up to 25 T parallel to the WSe2 plane lead to a partial brightening of the energetically lower lying exciton, leading to an increase of the dephasing time. Using a broadband femtosecond pulse excitation, the bright and partially allowed excitonic state can be excited simultaneously, resulting in coherent quantum beating between these states. The magnetic fields perpendicular to the WSe2 plane energetically shift the bright and dark excitons relative to each other, resulting in the hybridization of the states at the K and K' valleys. Our experimental results are well captured by time-dependent density functional theory calculations. These observations show that magnetic fields can be used to control the coherent dephasing and coupling of the optical excitations in atomically thin semiconductors.

Addressing violence against transgender people in Bangladesh: A call for policy intervention.

Violence, oppression, and cruelty are as old as human civilization itself. Human identity is multi-layered, and deviation from a specific identity may elicit violence, deprivation, and prejudice in various settings. In many countries and societies, the transgender community is one of the most vulnerable groups due to their gender incongruence. Deeply ingrained cultural norms, beliefs, social ignorance, and practices have transferred violence against transgender people over generations, preventing them from enjoying their fundamental human rights. Key objectives of this article are 2-fold: first, this article focuses on violence against transgender people and rights violation in Bangladesh; and second, the report examines the types of violence against the transgender population and the actors who must be involved in providing a solution. Moreover, this article unravels the current organizational and institutional advances in supporting the welfare and rights of the transgender community in Bangladesh. This article concludes that the absence of a dedicated national policy for the protection and welfare of the transgender population impedes the implementation of necessary measures, which should be facilitated by formulation of an appropriate policy, followed by effective implementation.