We have successfully grown GaSb and InGaSb quantum wells (QW) on a Si(001) substrate, and evaluated their optical properties using photoluminescence (PL). The PL emissions from the QWs at room temperature were observed at around 1.55 mu m, which is suitable for fiber optic communications systems. The measured ground state energy of each QW matched well with the theoretical value calculated by solving the Schrodinger equation for a finite potential QW. The temperature dependence of the PL intensity showed large activation energy (similar to 77.6 meV) from QW. The results indicated that the fabricated QW structure had a high crystalline quality, and the GaSb QW on Si for optical devices operating at temperatures higher than room temperature will be expected. (c) 2006 Elsevier B.V. All rights reserved.