Heterogeneous characteristics and absorption enhancement of refractory black carbon in an urban city of China.

In this study, field measurement was conducted using an integrated online monitoring system to characterize heterogeneous properties and light absorption of refractory black carbon (rBC). rBC particles are mainly from the incomplete combustion of carbonaceous fuels. With the data collected from a single particle soot photometer, thickly coated (BC) and thinly coated (BC) particles are characterized with their lag times.

Properties of Free Charge Carriers Govern Exciton Polarization in Plasmonic Semiconductor Nanocrystals.

Interaction between a plasmon, as a collective property of charge carriers, and electronic or spin states in complex nanostructures has emerged as one of the fascinating topics that intertwines the fields of photonics, optoelectronics, and spintronics. Here, we investigate the magneto-optical properties of plasmonic InN and CuSe nanocrystals and show that the complete exciton polarization induced by cyclotron motion of free carriers is a universal phenomenon in semiconductor nanocrystals. The selective exciton polarization is governed by the angular momentum transfer from the carriers following cyclotron orbits to the excited electronic band states and can be controlled by carrier type (electrons or holes), mass, and velocity.

Controlling the Mechanism of Excitonic Splitting in InO Nanocrystals by Carrier Delocalization.

Degenerately doped metal oxide nanocrystals have emerged as infrared plasmonic materials with promising applications in optoelectronics, surface-enhanced infrared spectroscopies, and sensing. They also have potential for technological applications in electronics and photonics owing to the possibility of coupling between plasmon and exciton in the absence of a heterojunction. Here, we demonstrate the control of excitonic splitting in InO nanocrystals upon excitation with circularly polarized light in an external magnetic field by simultaneous control of the electronic structure of donor defects and the nanocrystal host lattice.