Single-Atom Source in the Picokelvin Regime

An important aspect of the rapidly growing field of quantum atom optics is exploring the behavior of ultracold atoms at a deeper level than the mean field approximation, where the quantum properties of individual atoms becomes important. Major recent advances have been achieved with the creation and detection of reliable single-atom sources, which is a crucial tool for testing fundamental quantum processes. Here, we create a source comprised of a single ultracold metastable helium atom, which enables novel free-space quantum atom optics experiments to be performed with single massive particles with large de Broglie wavelengths

Catalysis in Petroleum Coking

The petroleum industry is challenged with the processing of present heavy crudes caused by high composition of sulfur and metals, which lead to a higher yield of unfavorable bottom product as vacuum residue. Vacuum residue is the least valuable fraction of four, such as saturates, aromatics, resins and asphaltenes. However, it can be upgraded to recover more valuable products such as light hydrocarbons. The Delayed Coking process is going to be used to transform the vacuum residue at different experimental conditions. First of all, the behavior of the vacuum residue needs to be analyzed with no additions in feedstock. Secondly, the vacuum residue can be mixed with unhydrogenated and hydrogenated light gas oil at different concentrations. Finally, the addition of different catalysts at various concentrations could be another method to achieve high yield of the desired product. Expected experimental conditions are 475oC for reactor temperature and bimetallic or trimetallic catalysts for the delayed coking process. In this research, 3 different catalysts will be tested in several proportions with respect to the weight of the feedstock material. The recommended feed concentration of light gas oil depends on the molecular structure of the vacuum residue and can be determined only by actual experiment. Based on these experimental conditions, a conclusion about the yield of the light hydrocarbons and ways to improving the process can be drawn

The Catalysis of Delayed Petroleum Coking

Due to the decreasing crude oil quality (heavier crudes and increasing contaminant concentrations) methods for upgrading residues from the refining process, such as coking, are becoming increasingly important. Delayed coking, a method by which residues are thermally cracked (large heavy molecules broken into smaller lighter molecules), produces liquid products and solid coke which can both be sold for further profit. In order to increase the amount of liquid products produced since they are the most value added product of the coking process catalysts (platinum on 0.5% alumina and nickel (skeletal),molybdenum promoted (1 wt%)) were tested to see how they would affect the process and products. Different ratios of vacuum residue, light gas oil, heavy gas oil, and catalyst were all loaded into a semi-batch reactor which operated under a nitrogen environment at 15 psi. Each ratio of components was tested at 450°C, 475°C, and 500°C. Gas chromatography based on ASTM D2887 was used to analyze gaseous products every 15 minutes during each test and the liquid products at the end. Testing is still ongoing and preliminary results have yet to be obtained. Due to the increased value of liquid products, catalysts and conditions which produce more of those are favored. Further research into these and other catalysts is recommended since residues from different crudes could interact differently with the catalysts

Precision Measurement for Metastable Helium Atoms of the 413 nm Tune-Out Wavelength at Which the Atomic Polarizability Vanishes

We present the first measurement for helium atoms of the tune-out wavelength at which the atomic polarizability vanishes. We utilize a novel, highly sensitive technique for precisely measuring the effect of variations in the trapping potential of confined metastable (2S13) helium atoms illuminated by a perturbing laser light field. The measured tune-out wavelength of 413.0938(9stat)(20syst)nm compares well with the value predicted by a theoretical calculation [413.02(9) nm] which is sensitive to finite nuclear mass, relativistic, and quantum electrodynamic effects. This provides motivation for more detailed theoretical investigations to test quantum electrodynamics

Solving the Quantum Many-Body Problem via Correlations Measured with a Momentum Microscope

In quantum many-body theory, all physical observables are described in terms of correlation functions between particle creation or annihilation operators. Measurement of such correlation functions can therefore be regarded as an operational solution to the quantum many-body problem. Here, we demonstrate this paradigm by measuring multiparticle momentum correlations up to third order between ultracold helium atoms in an s-wave scattering halo of colliding Bose-Einstein condensates, using a quantum many-body momentum microscope. Our measurements allow us to extract a key building block of all higher-order correlations in this system - the pairing field amplitude. In addition, we demonstrate a record violation of the classical Cauchy-Schwarz inequality for correlated atom pairs and triples. Measuring multiparticle momentum correlations could provide new insights into effects such as unconventional superconductivity and many-body localization.This work was supported through Australian Research Council (ARC) Discovery Project Grants No. DP120101390, No. DP140101763, and No. DP160102337. S. S. H. is supported by ARC Discovery Early Career Researcher Award No. DE150100315. A. G. T. is supported by ARC Future Fellowship Grant No. FT100100468

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts

The 42nd Symposium Chromatographic Methods of Investigating Organic Compounds : Book of abstracts. June 4-7, 2019, Szczyrk, Polan

Wheeler's delayed-choice gedanken experiment with a single atom

The wave-particle dual nature of light and matter and the fact that the choice of measurement determines which one of these two seemingly incompatible behaviours we observe are examples of the counterintuitive features of quantum mechanics. They are illustrated by Wheeler's famous 'delayed-choice experiment, recently demonstrated in a single-photon experiment. Here, we use a single ultracold metastable helium atom in a Mach-Zehnder interferometer to create an atomic analogue of Wheeler's original proposal. Our experiment confirms Bohr's view that it does not make sense to ascribe the wave or particle behaviour to a massive particle before the measurement takes place. This result is encouraging for current work towards entanglement and Bell's theorem tests in macroscopic systems of massive particles

Ghost imaging with atoms

Ghost imaging is a counter-intuitive phenomenon—first realized in quantum optics — that enables the image of a two-dimensional object (mask) to be reconstructed using the spatio-temporal properties of a beam of particles with which it never interacts. Typically, two beams of correlated photons are used: one passes through the mask to a single-pixel (bucket) detector while the spatial profile of the other is measured by a high-resolution (multi-pixel) detector. The second beam never interacts with the mask. Neither detector can reconstruct the mask independently, but temporal cross-correlation between the two beams can be used to recover a ‘ghost’ image. Here we report the realization of ghost imaging using massive particles instead of photons. In our experiment, the two beams are formed by correlated pairs of ultracold, metastable helium atoms3, which originate from s-wave scattering of two colliding Bose–Einstein condensates4, 5. We use higher-order Kapitza–Dirac scattering6, 7, 8 to generate a large number of correlated atom pairs, enabling the creation of a clear ghost image with submillimetre resolution. Future extensions of our technique could lead to the realization of ghost interference9, and enable tests of Einstein–Podolsky–Rosen entanglement9 and Bell’s inequalities10 with atoms

Ghost imaging with atoms and photons for remote sensing

Ghost imaging with correlated photon pairs has been applied to remote sensing without the spatially detected photons interacting with the object: here we demonstrate for the first time ghost imaging using correlated atom pairs.A.G.T. acknowledges the support of the Australian Research Council (ARC) through the Future Fellowship grant FT100100468 and the Discovery grant DP120101390. S.S.H. acknowledges the support of the ARC through the DECRA Fellowship DE150100315. We thank A. T. Friberg for discussions