Size control of InAs∕InP(001) quantum wires by tailoring P∕As exchange

The size and emission wavelength of self-assembled InAs∕InP(001) quantum wires (QWrs) is affected by the P∕As exchange process. In this work, we demonstrate by in situ stress measurements that P∕As exchange at the InAs∕InP interface depends on the surface reconstruction of the InAs starting surface and its immediate evolution when the arsenic cell is closed. Accordingly, the amount of InP grown on InAs by P∕As exchange increases with substrate temperature in a steplike way. These results allow us to engineer the size of the QWr for emission at 1.3 and 1.55 μm at room temperature by selecting the range of substrate temperatures in which the InP cap layer is grown.
This work was financed by Spanish MCyT under NANOSELF project (TIC2002-04096) and by NANOMAT project of the EC Growth Program, Contract No. G5RD-CT-2001-00545. One of the authors (D.F.) thanks the Spanish MECyD for funds. The authors also thank the Junta de Andalucía (PAI research group TEP-0120). TEM measurements were carried out in the DME-SCCYT and UCM.