Effects of Spin Fluctuations and Anomalous Thermal Expansion of delta-Plutonium

Details Effects of Spin Fluctuations and Anomalous Thermal Expansion of delta-Plutonium Effects of Spin Fluctuations and Anomalous Thermal Expansion of delta-Plutonium

2010-04-21

arxiv.org/abs/1004.3658v1

Physics

Condensed Matter

Materials Science

Scientific paper

We suggest a model for the magnetic dynamics of - plutonium and its alloys in order to show that the dynamical fluctuations of the magnetization density, or spin fluctuations, may be responsible for the anomalies of their observed thermal expansion. We show that due to strong magneto-elastic coupling, spin fluctuations may essentially contribute to the volume strain by giving a negative magneto-volume contribution that is proportional to the squared local magnetic moment and the magnetic Gruneisen constant which is negative in - plutonium. In the presented model, the local magnetic moment increases as the temperature rises, resulting in the interplay between the positive contributions to the volume strain from the lattice and the negative contribution from spin fluctuations, and finally leads to the Invar anomaly or to the negative coefficient of thermal expansion. Our results agree closely with the measured thermal expansion data for Pu-Ga alloys.

Affiliated with

Also associated with

No associations

Rating

Effects of Spin Fluctuations and Anomalous Thermal Expansion of delta-Plutonium does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Effects of Spin Fluctuations and Anomalous Thermal Expansion of delta-Plutonium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effects of Spin Fluctuations and Anomalous Thermal Expansion of delta-Plutonium will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-326572