Instability and charge density wave of metallic quantum chains on a silicon surface

Self-assembled indium linear chains on the Si(lll) surface are found to exh ibit instability of the metallic phase and 1D charge density wave (CDW). Th e room-temperature metallic phase of these chains undergoes a temperature-i nduced, reversible transition into a semiconducting phase. The 1D CDW along the chains is observed directly in real space by scanning tunneling micros copy at low temperature. The Fermi contours of the metallic phase measured by angle-resolved photoemission exhibit a perfect nesting predicting precis ely the CDW periodicity. [S0031-9007(99)09330-8].