Break-junction experiments on the Kondo semiconductor CeNiSn: tunnelling versus direct conductance

8 J an 2 00 1 Is CeNiSn a Kondo semiconductor ? - break - junction experiments

We investigated break junctions of the Kondo semiconductor CeNiSn, both in the metallic and in the tunnelling regime, at low temperatures and in magnetic fields up to 8T. Our experiments demonstrate that direct CeNiSn junctions have typical metallic properties instead of the expected semiconducting ones. There is no clear-cut evidence for an energy (pseudo)gap. The main spectral feature, a pron...

Tuning the Kondo effect with a mechanically controllable break junction.

We study electron transport through C(60) molecules in the Kondo regime using a mechanically controllable break junction. By varying the electrode spacing, we are able to change both the width and the height of the Kondo resonance, indicating modification of the Kondo temperature and the relative strength of coupling to the two electrodes. The linear conductance as a function of T/T(K) agrees w...

Gap Structures of A-15 Alloys from the Superconducting and Normal-State Break-Junction Tunnelling

Kondo effect in a neutral and stable all organic radical single molecule break junction.

Organic radicals are neutral, purely organic molecules exhibiting an intrinsic magnetic moment due to the presence of an unpaired electron in the molecule in its ground state. This property, added to the low spin-orbit coupling and weak hyperfine interactions, make neutral organic radicals good candidates for molecular spintronics insofar as the radical character is stable in solid state electr...

Break–junction Tunneling on Mgb 2

Tunneling data on magnesium diboride, MgB2, are reviewed with a particular focus on superconductor–insulator–superconductor (SIS) junctions formed by a break–junction method. The collective tunneling literature reveals two distinct energy scales, a large gap, ∆L ∼ 7.2 meV, close to the expected BCS value, and a small gap, ∆S ∼ 2.4 meV. The SIS break junctions show clearly that the small gap clo...