Tuning the electronic and magnetic properties of graphene-like AlN nanosheets by surface functionalization and thickness.

In this paper, the structural, electronic, and magnetic properties as well as the relative stabilities of fully and partially hydrogenated AlN nanosheets have been systematically investigated by first-principles calculations based on density functional theory. The results indicate that full hydrogenation is more energetically favorable for thinner AlN nanosheets, whereas semi-hydrogenation at N sites is preferred for thicker ones. Moreover, semiconductor → half-metal → metal transition with nonmagnetic → magnetic transfer can be achieved for AlN nanosheets by surface hydrogenation and increasing nanosheet thickness. The diverse electronic and magnetic properties highlight the potential applications of AlN nanosheets in electronics and spintronics.

Development of beam emission spectroscopy diagnostic on EAST.

Beam Emission Spectroscopy (BES) diagnostic based on Neutron Beam Injection (NBI) on the Experimental Advanced Superconducting Tokamak has been developed. This system consists of 16 × 8 channels which can diagnose the density fluctuation in a rectangular area of about 20 × 10 cm2 in the cross section, whose radial position is adjustable from the core to edge just by means of changing the angle of the rotation mirror. The spatial resolution is about 1-3 cm according to the diagnosed radial position. The temporal resolution is 1 µs. Space calibration of the diagnostic system is done based on the reversibility of the optical path. The NBI modulation experiment shows the success of BES development.