Structural modifications induced by electronic energy loss in Ni₃B irradiated with GeV heavy ions^*

¹ Laboratoire de Physique de la Matière Condensée ( ERS-CNRS 5646), Service National des Champs Magnétiques Pulsés, INSA, Complexe Scientifique de Rangueil, 31077 Toulouse, France
² Laboratoire des Solides Irradiés, Commissariat à l'Énergie Atomique, École Polytechnique, 91128 Palaiseau Cedex, France
³ Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse (IN2P3-CNRS), Bâtiment 108, 91405 Orsay campus, France

Corresponding author: annie.dunlop@polytechnique.fr

Received: 26 November 1997
Revised: 10 April 1998
Accepted: 15 April 1998
Published online: 15 August 1998

Abstract

Crystalline Ni₃B samples have been irradiated with GeV heavy ions (from ¹⁶O to ²³⁸U) at low temperature in order to study the damage induced in this compound by ion electronic energy loss. Electrical resistance measurements were performed in situ during irradiation and during annealing. Subsequent X-ray diffraction data and transmission electron microscopy observations reveal a change of the radiation damage process as a function of the electronic stopping power (dE/dx)_e. At low (dE/dx)_e isolated defects are created, while at high (dE/dx)_e irradiation generates continuous amorphous tracks. Amorphous inclusions (discontinuous tracks) are most likely formed in the intermediate (dE/dx)_e range. The amorphous phase induced by swift heavy ion irradiation, different from that formed by quenching techniques, is unstable at room temperature over a period of a few months.