Observation of a pseudogap in α-AlMnSi by break-junction tunneling spectroscopy

Abstract Tunneling spectroscopy studies of an α-Al9Mn1.8Si2 single crystal were made at 4.2 K with the break-junction technique. A narrow dip at zero bias (V=0) with peaks on both sides was observed in the spectrum, which corresponds to a pseudogap of 25 meV in the density of states. The dense set of sharp spikes predicted by the band calculations for the crystal was not observed.