Tchernycheva Maria, Cirlin George E, Patriarche Gilles, Travers Laurent, Zwiller Valery, Perinetti Umberto, Harmand Jean-Christophe
CNRS-LPN, Route de Nozay, 91460 Marcoussis, France.
Nano Lett. 2007 Jun;7(6):1500-4. doi: 10.1021/nl070228l. Epub 2007 May 5.
We report on the fabrication by Au-assisted molecular beam epitaxy of InP nanowires with embedded InAsP insertions. The growth temperature affects the nucleation on the nanowire lateral surface. It is therefore possible to grow the wires in two steps: to fabricate an axial heterostructure (at 420 degrees C), and then cover it by a shell (at 390 degrees C). The InAsP alloy composition could be varied between InAs0.35P0.65 and InAs0.5P0.5 by changing the As to P flux ratio. When a shell is present, the InAsP segments show strong room-temperature photoluminescence with a peak wavelength tunable from 1.2 to 1.55 mum by adjusting the As content. If the axial heterostructure has no shell, luminescence intensity is drastically reduced. Low-temperature microphotoluminescence performed on isolated single wires shows narrow peaks with a line width as small as 120 microeV.
我们报道了通过金辅助分子束外延法制备嵌入InAsP插入段的InP纳米线。生长温度会影响纳米线侧面的成核。因此，可以分两步生长纳米线：先制造轴向异质结构（在420摄氏度下），然后用壳层覆盖（在390摄氏度下）。通过改变砷与磷的通量比，InAsP合金成分可以在InAs0.35P0.65和InAs0.5P0.5之间变化。当存在壳层时，InAsP段在室温下表现出强烈的光致发光，通过调节砷含量，其峰值波长可在1.2至1.55微米之间调谐。如果轴向异质结构没有壳层，发光强度会急剧降低。对孤立的单根纳米线进行的低温微光致发光显示出窄峰，线宽小至120微电子伏特。
