Charge density waves affected by Rb nanowire network formation on 1T-TaS2

Alkali metals tend to either intercalate or adsorb on layered materials. Wi th sufficient kinetic energy of the impinging atoms Rb forms nanowire netwo rks on surfaces of transition metal dichalcogenides [R. Adelung, L. Kipp, J . Brandt, L. Tarcak, M. Traving, C. Kreis, M. Skibowski, Appl. Phys. Lett. 74 (1999) 3053]. This contrasts earlier results discussing alkali metal exp osure to layered 1T-TaS2 crystals in terms of intercalation phenomena [C, P ettenkofer, W. Jaegermann, Phys. Rev. B 50 (1994) 8816; I. Ekvall, H.E. Bra uer, E. Wahlstrom, H. Olin, Phys. Rev. B 59 (1999) 7751]. We show that Rb e xposure to 1T-TaS2 may result in nanowire networks that drastically affect the charge density wave (CDW) phases of 1T-TaS2. By combined application of synchrotron radiation excited angle-resolved photoemission spectroscopy, s canning tunneling microscopy (STM) and LEED, the change in electronic struc ture leading to a new room temperature phase can be related to the network geometry. (C) 2000 Elsevier Science B.V. All rights reserved.