SAIP 2011 Support
Thermal and electronic transport studies of the Kondo energy scale in the heavy-fermion system CeCu5-xAlx
Presented by Prof. Andre STRYDOM on 13 Jul 2011 from 17:00 to 19:00
Type: Poster Presentation
Track: Track A - Condensed Matter Physics and Material Science
<p>The binary compound CeCu<sub>5</sub> is an archetypal heavy-fermion Kondo lattice with an antiferromagnetic ground state. Strong hybridization effects between the localized 4f-electron moment and conduction electrons result in incoherent spin scattering in the electronic transport at high temperatures, but with an effective magnetic moment nearly equal to that of the free-ion Ce<sub>3+</sub> state. Long-range magnetic ordering at T<sub>N</sub> = 3.9 K and the Kondo temperature T<sub>K</sub>=2.2 K are of similar energy scales, making this system ideally suited to studies of competing magnetic interactions in the strongly correlated electron class of systems. In this work we synthesized a series of pseudo-binary compounds CeCu<sub>5-x</sub>Al<sub>x</sub>. The dilution of Cu by Al results in augmenting the electronic density of states close to the Fermi energy, which is also the location of the magnetic and hybridized 4f electron levels resonance. Our studies of the temperature and magnetic field dependencies of thermoelectric power and electrical resistivity in the CeCu<sub>5-x</sub>Al<sub>x</sub> series of compounds will be discussed in terms of comparitive calculations of the Kondo energy scale from data of magnetoresistivity (the single-ion Bethe Ansatz theory) and from the thermoelectric power (phenomenological description in presence of intermediate valency) by means of two different theoretical models.
Level (Hons, MSc, PhD, other)?
Consider for a student award (Yes / No)?