Phase transformations in oxides induced by swift heavy ions

It is now well established that the high electronic energy loss released by swift heavy ions in solid materials can lead to different final manifestations like modification of defect concentration, atomic transport, phase transformation and track formation. The subject is quite vast and this contribution therefore concentrates oil phase transformations in oxides. After a brief overview of the most significant findings obtained in this research field, a special attention is paid to zirconia and hafnia which both transform from the monoclinic to the tetragonal phase. In fact, the likeness of these materials offers the unique opportunity to impose drastic constraints oil the possible models proposed to explain the creation of atomic movements in the wake of swift heavy ions. The comparison of the experimental results with the models' predictions clearly suggests that the thermal spike is the right process which governs the transition from the monoclinic to the tetragonal phase in zirconia and hafnia. (c) 2005 Elsevier B.V. All rights reserved.