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11.
12.
Ericsson M Achilles D Barreiro JT Branning D Peters NA Kwiat PG 《Physical review letters》2005,94(5):050401
Geometric phase may enable inherently fault-tolerant quantum computation. However, due to potential decoherence effects, it is important to understand how such phases arise for mixed input states. We report the first experiment to measure mixed-state geometric phases in optics, using a Mach-Zehnder interferometer, and polarization mixed states that are produced in two different ways: decohering pure states with birefringent elements; and producing a nonmaximally entangled state of two photons and tracing over one of them, a form of remote state preparation. 相似文献
13.
We experimentally demonstrate the first quantum system entangled in every degree of freedom (hyperentangled). Using pairs of photons produced in spontaneous parametric down-conversion, we verify entanglement by observing a Bell-type inequality violation in each degree of freedom: polarization, spatial mode, and time energy. We also produce and characterize maximally hyperentangled states and novel states simultaneously exhibiting both quantum and classical correlations. Finally, we report the tomography of a 2 x 2 x 3 x 3 system (36-dimensional Hilbert space), which we believe is the first reported photonic entangled system of this size to be so characterized. 相似文献
14.
In this paper we study the variability reduction gain that results from the use of multiweighing proceedings in packing processes
with the objective of sales at constant nominal weights. According to this, we have proposed a packing algorithm that includes
the formation of units with variable number of pieces and we have obtained the value of the percentage variability reduction
index.
Collaborator in the Catalan Institute of Tecnology (ICT). 相似文献
15.
This paper deals with robustness of adaptive control of continuoussystems subject to known output delay, input saturation, unmodelledlinear dynamics, and bounded disturbances. A simple gradient-typealgorithm with a relative deadzone is used. The relative deadzoneis built with an estimated contribution of the unmodelled dynamicsto the system output. The basic tool used for stability androbustness analysis is Gronwall's lemma. 相似文献
16.
Ch. Berger H. Genzel R. Grigull W. Lackas F. Raupach A. Klovning E. Lillestöl E. Lillethun J.A. Skard H. Ackermann F. Barreiro J. Bürger L. Criegee H.C. Dehne R. Devenish A. Eskreys G. Flügge K. Wacker 《Physics letters. [Part B]》1980,91(1):148-151
We have performed a search for narrow resonances in the center of mass energy range from 29.90 to 31.46 GeV using the e+e? storage ring PETRA at DESY. We present the total cross section for hadron production and an upper limit for resonance production, indicating that no bound state of charge- quarks exists in this energy range. 相似文献
17.
Paul Baret Eliezer Barreiro Andrew E. Greene Jean-Louis Luch Marco-Antonio Teixeira Pierre Crabbe 《Tetrahedron》1979,35(24):2931-2938
New allenic prostanoids 5c, d, 7,9c, and 15b have been prepared by total synthesis. In each case a cuprate-propargylic acetate reaction was used as the key step. 相似文献
18.
Summary In this paper we study the variability reduction gain in the production processes that require a process of packing with the
objective of sales at constant nominal weights. We have obtained the value of the percentage variability reduction index in
the packing processes of units formed by a fixed number of pieces attending to random packing and multiple weighting with
variable number of scaling pan packing criteria. These indexes have been obtained both for only one packing objective processe
and for double objective packing processes.
Collaborator in the Catalan Institute of Technology (ICT). 相似文献
19.
Ch. Berger H. Genzel R. Grigull W. Lackas F. Raupach A. Klovning E. Lillestöl E. Lillethun J.A. Skard H. Ackermann G. Alexander F. Barreiro J. Bürger L. Criegee H.C. Dehne R. Devenish A. Eskreys K. Wacker 《Physics letters. [Part B]》1980,95(2):313-317
Measurements of the charged multiplicities for hadron production in e+e? annihilation in the center of mass energy range 9–32 GeV have been made. The average charged multiplicity has an energy dependence much stronger than ln s and similar to that reported for pp collisions. Quantitative differences are observed in the magnitude of both the average multiplicity 〈nch〉 and the dispersion Dch for e+e? and pp interactions at the same center of mass energy. 〈nch〉 and the ratio 〈nch/Dch in e+e? annihilations are significantly larger than in pp collisions and are found to be in overall agreement with QCD predictions. KNO scaling is seen to be satisfied. 相似文献
20.
Barreiro A Hampel S Rümmeli MH Kramberger C Grüneis A Biedermann K Leonhardt A Gemming T Büchner B Bachtold A Pichler T 《The journal of physical chemistry. B》2006,110(42):20973-20977
A new method to grow bulk quantities of single-walled carbon nanotubes (SWCNTs) by a catalytic chemical vapor deposition (CVD) process with the possibility of varying the pressure has been developed and is reported in this paper. Thermal decomposition of ferrocene provides both catalytic particles and carbon sources for SWCNT growth using Ar as a carrier gas. Upon an increase in the pressure, the mean diameter of the SWCNTs decreases. In fact, high abundances of SWCNT with diameters as small as 0.7 nm, which is the limit for stable caps with isolated pentagons, can be obtained. An additional advantage of this method is that as no external carbon sources are required, SWCNT synthesis can be achieved at temperatures as low as 650 degrees C. 相似文献