Received Month X, XXXX; revised Month X, XXXX; accepted Month X, XXXX; posted Month X, XXXX (Doc. ID XXXXX); published Month X, XXXX Using a 7.5 micron diameter disk fabricated with III-V-on-silicon fabrication technology, we demonstrate bias-free alloptical wavelength conversion for non-return to zero on-off keyed pseudo-random bit sequence data at the speed of 10Gbps with an extinction ratio of more than 12dB. The working principle of such a wavelength converter is based on the free carrier induced refractive index modulation in a pump-probe configuration. We believe it to be the first bias-free on-chip demonstration of all-optical wavelength conversion using pseudo-random bit sequence data. All-optical gating measurements in the pump-probe configuration with the same device have revealed that it's possible to achieve wavelength conversion beyond 20 Gbps.© 2011 Optical Society of America OCIS Codes: 130.3120, 130.3990, 130.7405, 230.1150 In the past decade there has been an increased focus on the use of the mature CMOS compatible silicon-oninsulator (SOI) fabrication technology for realizing different photonic components and devices. Until now only few researchers have reported on the use of III-V/SOI fabrication technology for realizing photonic switching devices required for ultra-fast information processing. The rationale to use hybrid III-V/SOI technology lies in the fact that, at present, the III-V/SOI technology has been used to realize the most advanced devices and most advanced photonic integrated circuits ( Owing to their smaller achievable size and enhanced nonlinearity originating from the resonant behaviour along with high optical confinement, microdisks/rings are considered to be promising building blocks for high density PICs. So far ultra-fast (of the order of 10 Gbps) alloptical switching, modulation and wavelength conversion in microrings/disks on the SOI platform has been demonstrated using reverse bias [2], ion implantation [4] and forward bias [5]. Realization of bias-free on-chip alloptical functions results in easy packaging of the chips due to the reduced number of pins required.In our previous work [6] we demonstrated 10GHz alloptical gating in a 10 µm diameter III-V/SOI disk but the use of reverse bias was necessary to achieve this speed and the extinction ratio was only 4.5dB. Using the same concept as in ref.[6], here we report on all-optical wavelength conversion of a non-return to zero (NRZ) onoff keyed (OOK) pseudo-random bit sequence (PRBS) data signal at the speed of 10Gbps in a 7.5µm diameter III-V(InGaAsP-InP)/SOI microdisk. The microdisks are fully fabricated in a CMOS pilot line. The III-V stack is molecularly bonded on top of the SOI waveguide circuit and the microdisks are defined by deep ultra-violet (DUV) lithography. A full description on the fabrication will be reported elsewhere [7]. Before proceeding to dynamic all-optical wavelength conversion experiments, all-optical gating measurements were performed to estimate the achievable speed and corresponding power con...