- Full text PDF available (5)
We present a new linear-depth ripple-carry quantum addition circuit. Previous addition circuits required linearly many ancillary qubits; our new adder uses only a single ancillary qubit. Also, our circuit has lower depth and fewer gates than previous ripple-carry adders.
We study the suitability of the additive lagged-Fibonacci pseudorandom number generator for parallel computation. This generator has relatively short period with respect to the size of its seed. However, the short period is more than made up for with the huge number of full-period cycles it contains. These diierent full-period cycles are called equivalence… (More)
We describe in detail the parallel implementation of a family of additive lagged-Fibonacci pseudorandom number generators. The theoretical structure of these generators is exploited to preserve their well-known randomness properties and to provide a parallel system of distinct cycles. The algorithm presented here solves the reproducibility problem for a far… (More)
Ensuring that pseudorandom number generators have good randomness properties is more complicated in a multiprocessor implementationthan in the uniprocessor case. We discuss simple extensions of uniprocessor testing for SIMD parallel streams, and develop in detail a repeatability test for the SPMD paradigm. Examples of the application of these tests to an… (More)
We study the suitability of the additive lagged-Fibonacci pseudorandom number generator for parallel computation. This generator has a relatively short period with respect to the size of its seed. However, the short period is more than made up for with the huge number of full-period cycles it contains. We call these diierent full-period cycles equivalence… (More)
We summarize some of the recent developments of our research group and of other groups in the design and analysis of pseudorandom number generators for massively parallel computers. The three parallelization techniques we will consider in detail for mapping pseudorandom streams onto distinct parallel processes are: 1. Splitting maximal-period generators'… (More)
A new experimental setup has been developed to enable in situ studies of catalyst surfaces during chemical reactions by means of surface x-ray diffraction (SXRD) and grazing incidence small angle x-ray scattering. The x-ray reactor chamber was designed for both ultrahigh-vacuum (UHV) and reactive gas environments. A laser beam heating of the sample was… (More)