Anisotropic crystallization in solution processed chalcogenide thin film   by linearly polarized laser
  The low activation energy associated with amorphous chalcogenide structures offers broad tunability of material properties with laser-based or thermal processing. In this paper, we study near-bandgap laser induced anisotropic crystallization in solution processed arsenic sulfide. The modified electronic bandtail states associated with laser irritation lead to a distinctive photoluminescence spectrum, compared to thermally annealed amorphous glass. Laser crystalized materials exhibit a periodic subwavelength ripples structure in transmission electron microscopy experiments and show polarization dependent photoluminescence. Analysis of the local atomic structure of these materials using laboratory-based X-ray pair distribution function analysis indicates that laser irradiation causes a slight rearrangement at the atomic length scale, with a small percentage of S-S homopolar bonds converting to As-S heteropolar bonds. These results highlight fundamental differences between laser and thermal processing in this important class of materials. 
Tingyi Gu, Hyuncheol Jeong, Kengran Yang, Fan Wu, Nan Yao, Rodney D.   Priestley, Claire E. White and Craig B. Arnold
cond-mat.mtrl-sci cond-mat.mes-hall physics.optics