William M. J. Green

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We demonstrate the generation of a supercontinuum in a 2 cm long silicon wire by pumping the wire with mid-infrared picosecond pulses in the anomalous dispersion regime. The supercontinuum extends from 1535 nm up to 2525 nm for a coupled peak power of 12.7 W. It is shown that the supercontinuum originates primarily from the amplification of background(More)
—An investigation of signal integrity in silicon pho-tonic nanowire waveguides is performed for wavelength-division-multiplexed optical signals. First, we demonstrate the feasibility of ultrahigh-bandwidth integrated photonic networks by transmitting a 1.28-Tb/s data stream (32 wavelengths 40-Gb/s) through a 5-cm-long silicon wire. Next, the crosstalk(More)
An InGaAsP-InP optical switch geometry based on electrical control of waveguide-resonator coupling is demonstrated. Thermooptic tuning of a Mach-Zehnder interferometer integrated with a racetrack resonator is shown to result in switching with ON-OFF contrast up to 18.5 dB. The optical characteristics of this unique design enable a substantial reduction of(More)
We measure signal degradation from inter-channel crosstalk of ultrahigh-bandwidth signals in silicon-on-insulator waveguides, and single-channel power penalty over a range of injection powers. The results validate the suitability of silicon-based nanowire interconnects for broadband WDM networks. Introduction Photonic integrated circuits (PICs) present the(More)
—A novel class of circular resonators, based on a radial defect surrounded by Bragg reflectors, is studied in detail. Simple rules for the design and analysis of such structures are derived using a transfer matrix formalism. Unlike conventional ring res-onators, annular Bragg resonators (ABR) are not limited by the total internal reflection condition and(More)
Silicon photonics has recently been proposed for a diverse set of applications at mid-infrared wavelengths 1, 2 , the implementation of which require on-chip photodetectors. In planar geometries, dopant-based extrinsic photoconductors have long been used for mid-infrared detection with Si and Ge acting as host materials 3. Leveraging the dopant-induced(More)
We demonstrate digital tuning of the slow-light regime in silicon photonic-crystal waveguides by performing atomic layer deposition of hafnium oxide. The high group-index regime was deterministically controlled ͑redshift of 140Ϯ 10 pm per atomic layer͒ without affecting the group-velocity dispersion and third-order dispersion. Additionally, differential(More)
CMOS-compatible Si⁺-implanted Si-waveguide p-i-n photodetectors operating at room temperature and at mid-infrared wavelengths from 2.2 to 2.3 µm are demonstrated. Responsivities of 9.9 ± 2.0 mA/W are measured at a 5 V reverse bias with an estimated internal quantum efficiency of 2.7 - 4.5%. The dark current is found to vary from a few microamps down to less(More)