Robert W. Hellwarth

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A cellular auto mata approach t o fast addit ion of binary numbers is pr esented. This ap proach utilizes the intrinsically parallel nature of the cellular auto mat on to add binary numbers represented as on/off pix els on the computer scree n. Numbers n-bit long are added serially pairwise until the final sum is ob t ained. This approach can eas ily be(More)
We discuss exact solutions of Maxwell's equations that describe the evolution of single-cycle electromagnetic pulses. The solutions are applied to recent observations of the diffraction transformation of terahertz pulses. In particular, we elucidate the role of the Gouy shift in the temporal reshaping and polarity reversals of single-cycle terahertz pulses.
We report tributary channel data traffic grooming/exchange of pol-muxed DPSK signal based on Kerr-induced nonlinear polarization rotation. 8 tributary channel data grooming between two pol-muxed 80-Gbit/s DPSK channels is demonstrated with a penalty of <4 dB.
A dr iver mechanism is introduced to a cellular automat on by whi ch the state of one or several cells is controlled indep endently of t he ot her cells. On e way of achieving t his is to set cert ain cell valu es usin g a sep ar at e rul e governed by external inputs t o the cellular automaton. When such a mechanism is used in t he Life ru le, on e-dim(More)
We propose and demonstrate an all-optical tunable phase-preserving scheme for amplitude regeneration of amplitude modulated signals and phase modulated signals based on coherent optical nonlinear wave mixing using HNLF. A regeneration factor of 7 for OOK and a regeneration factor of 2.9 for BPSK are achieved.
We experimentally demonstrate a tunable optical generation of up to 40-Gbaud 16-QAM from a QPSK signal using a variable DGD element based on vector addition between two polarization states. We also show the baud rate tunability and investigate the tolerance of 16-QAM generation to the DGD offset.
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