Abstract
We present a study of the magnetic field-dependent thermal transport in the spin chain material (NENP). The measured thermal conductivity is found to be very sensitive to the field-induced changes in the spin excitation spectrum. The magnetic contribution to the total heat conductivity is analyzed in terms of a quasiparticle model, and we obtain a temperature and momentum independent mean free path. This implies that the motion of quasiparticles is effectively three dimensional despite the tiny interchain coupling.
- Received 24 December 2007
DOI:https://doi.org/10.1103/PhysRevLett.100.137202
©2008 American Physical Society