title: In-chain tunneling through charge-density-wave nanoconstrictions and break junctions.
abstract: We have fabricated longitudinal nanoconstrictions in the charge-density wave conductor (CDW) NbSe3 using a focused ion beam and using a mechanically controlled break-junction technique. Conductance peaks are observed below the TP1=145 K and TP2=59 K CDW transitions, which correspond closely with previous values of the full CDW gaps 2Delta1 and 2Delta2 obtained from photoemission. These results can be explained by assuming CDW-CDW tunneling in the presence of an energy gap corrugation epsilon2 comparable to Delta2, which eliminates expected peaks at +/-|Delta1+Delta2|. The nanometer length scales our experiments imply indicate that an alternative explanation based on tunneling through back-to-back CDW-normal-conductor junctions is unlikely.
authors.affiliation: Kavli Institute of Nanoscience Delft, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands.
authors.forename: K
authors.initials: K
authors.lastname: O'Neill
authors.forename: E
authors.initials: E
authors.lastname: Slot
authors.forename: R E
authors.initials: RE
authors.lastname: Thorne
authors.forename: H S J
authors.initials: HS
authors.lastname: van der Zant