Sn doped GeO_2 nanowires with waveguiding behavior

Abstract

Sn doped GeO_2 nanowires and microwires have been grown by an evaporation-deposition method, using a mixture of Ge and SnO_2 powders as precursors. Comparison with undoped GeO_2 nanowires grown by the same method shows that the presence of Sn prevents the formation of sharp bends, which makes the wires more suitable for waveguiding applications. Incorporation of about 0.5 at.% of Sn into the wires influences their morphology and gives rise to wires showing two different cross-sectional dimensions along the growth axis. Sn does not influence the luminescence spectra in the visible range but causes the appearance of emission bands in the near-infrared range. The waveguiding behavior of the Sn doped wires for green and red laser light has been demonstrated.