|About this Abstract
||MS&T21: Materials Science & Technology
||Probing Defect Properties and Behavior under Mechanical Deformation and Extreme Conditions
||Switching the Fracture Toughness of Single Crystal ZnS by Light Irradiation
||Tingting Zhu, Kuan Ding, Anahid Amiri, Yu Oshima, Enrico Bruder, Robert W. Stark, Karsten Durst, Katsuyuki Matsunaga, Atsutomo Nakamura, Xufei Fang
|On-Site Speaker (Planned)
An enormous change of the dislocation-mediated plasticity has been found in bulk semiconductor that exhibits the photoplastic effect. In this talk, we report that the UV (365 nm) light irradiation during mechanical testing dramatically decreases the fracture toughness of ZnS. The crack tip toughness on a (001) single-crystal ZnS, as measured by the near-tip crack opening displacement method, is increased by ~45% in complete darkness compared to that in UV light. The increase of fracture toughness is attributed to a significant increase of the dislocation mobility in darkness, as explained by the crack tip dislocation shielding model. Our finding suggests a route towards controlling the fracture toughness of photoplastic semiconductors by tuning the light irradiation.