## Abstract

Effects of pressure P on the magnetic moment M and the Curie temperature T _{C} have been investigated for La(Fe _{x}Si _{1-x})] _{13} above and below the magnetic phase boundary concentration x = 0.86. where the ferromagnetic-paramagnetic transition at T _{C} changes from the first-order (x ≥ 0.86) to the second-order (x < 0.86). The pressure coefficient of M exhibits a sluggish variation against concentration and no anomaly was observed at x = 0.86. being consistent with the Landau expansion model. On the other hand. T _{C} for the second-order transition has a large negative pressure coefficient dT _{C}/dP and its magnitude increases with increasing x. Above x = 0.86, the magnitude of dT _{C}/dP for the first-order transition increases with x, contrary to the theoretical expectation. It has been revealed that the spin-wave dispersion coefficient becomes smaller when the first-order transition becomes clear by changing the concentration and also applying pressure. Consequently, it is plausible that dT _{C}/dP above x = 0.86 is enhanced by the increase of instability of the ferromagnetic state.

Original language | English |
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Pages (from-to) | 478-481 |

Number of pages | 4 |

Journal | Materials Transactions |

Volume | 47 |

Issue number | 3 |

DOIs | |

Publication status | Published - 2006 Mar |

## Keywords

- Itinerant-electron metamagnetism
- Magnetovolme effect
- Spin fluctuation
- Spin-wave dispersion coefficient

## ASJC Scopus subject areas

- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering