2D tungsten disulfide monolayer tagged posts

Peering into Building Blocks of Galaxies

Peering into building blocks of galaxies

An image of Camargo 791, one of the newly found embedded clusters. Credit: Camargo et al.

When a giant cloud of molecular gas condenses, star clusters are born. It may sound simple but the formation of star clusters is a very complex process. By peering into this process we could get valuable information on the evolution of galaxies and improve our knowledge about large cosmic structures in the universe. “Star clusters are often considered as building blocks of galaxies. Understanding how these objects form and evolve is vital to our comprehension of the structure, formation and evolution of galaxies,” Denilso Camargo.

Camargo and his colleagues recently discovered a multitude of star clusters using NASA’s Wide-field Infrared Survey Explorer: 652 star clusters, stellar groups and candidate...

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Laser Spectroscopy of Ultrathin Semiconductor reveals rise of ‘Trion’ Quasiparticles: central to Energy Apps

In a pump-probe experiment, the pump laser pulse first excites the 2D material, and later, at controllable time-delays, the probe laser pulse returns to the energy-pumped site to provide information about the evolution of the pump’s effect on the material. In the ORNL experiment, absorption of pumped energy first generated two excitons, X1 and X2. Dissociation of these excitons through hole trapping at the substrate freed their electrons. Then the arriving probe pulse generated new electron–hole pairs, which joined the remaining free electrons to form trions T1 and T2. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

In a pump-probe experiment, the pump laser pulse first excites the 2D material, and later, at controllable time-delays, the probe laser pulse returns to the energy-pumped site to provide information about the evolution of the pump’s effect on the material. In the ORNL experiment, absorption of pumped energy first generated two excitons, X1 and X2. Dissociation of these excitons through hole trapping at the substrate freed their electrons. Then the arriving probe pulse generated new electron–hole pairs, which joined the remaining free electrons to form trions T1 and T2. Credit: Oak Ridge National Laboratory, U.S. Dept. of Energy

Quasiparticles – excitations that behave collectively like particles – can be difficult to detect...

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