Crystallochemistry and Kondo-like behaviour of the thorium and uranium arsenoselenides

Interaction between TLS and the conduction electronsin actinide arsenoselenides: a high‐pressure study

“…Details concerning sample preparation as well as their crystallochemical analysis are described in [7]. Since growing conditions resulted mainly in plate-like crystals of the thickness less than 1 mm, the electrical resistance has been investigated in the basal plane, only.…”

Electrical transport properties of USbSe and USbTe

“…Additionally, yet in the case of UPS and UAsSe only, below about 0.5T C the resistivity exhibits an anomalous upturn towards low temperatures [6,7,9]. This latter feature has recently attracted much attention being interpreted [6,9,10] in terms of non-magnetic Kondo effect in a two-level-system (TLS) scenario [11]. It was argued that the Kondo-like resistivity behavior arises in UPS and UAsSe due to anion disorder, i.e.…”

Orbital Kondo behavior from dynamical structural defects

“…For a special class of parameters the renormalized energy splitting between the lowest two levels is around T K implying that such dynamical defects may give rise to some of the Kondo-like anomalies observed [1,3,6]. Our calculations also indicate that to obtain a measurable T K one needs resonant scattering on the defect.…”

“…The best candidates are therefore atoms with resonant d or f-scattering at the Fermi energy or possibly small groups of atoms [25]. Thus dynamical local defects with special realistic model parameters can explain the Kondo-like anomalies observed in some experiments for T > T K [1,3,6]. Note that in amorphous materials the positions of the defect f -or d-orbitals have usually a distribution, and therefore many of the defects may have resonant scattering at the Fermi energy.…”