Daniel J. Miller

A method of manufacturing an orthotropic deck panel includes cambering a deck plate of the orthotropic deck panel to a first degree of camber in a longitudinal direction, cambering the deck plate to a second degree of camber in a transverse direction, and attaching a rib member of the orthotropic deck panel to the deck plate by welding the rib member to the deck plate. The first degree of camber corresponds to a shape of a surface of which the orthotropic deck panel is a part, and the second degree of camber is configured such that the deck plate is flatter in the transverse direction after the rib member is welded to the deck plate than when the deck plate is being cambered in the transverse direction.

The sector length distribution (SLD) of a quantum state is a collection of local unitary invariants that quantify -body correlations. We show that the SLD of graph states can be derived by solving a graph-theoretical problem. In this way, the mean and variance of the SLD are obtained as simple functions of efficiently computable graph properties. Furthermore, this formulation enables us to derive closed expressions of SLDs for some graph state families. For cluster states, we observe that the SLD is very similar to a binomial distribution, and we argue that this property is typical for graph states in general. Finally, we derive an SLD-based entanglement criterion from the majorization criterion and apply it to derive meaningful noise thresholds for entanglement.

A central building block of many quantum algorithms is the diagonalization of Pauli operators. Although it is always possible to construct a quantum circuit that simultaneously diagonalizes a given set of commuting Pauli operators, only resource-efficient circuits are reliably executable on near-term quantum computers. Generic diagonalization circuits can lead to an unaffordable Swap-gate overhead on quantum devices with limited hardware connectivity. A common alternative is excluding two-qubit gates, however, this comes at the cost of restricting the class of diagonalizable sets of Pauli operators to tensor product bases (TPBs). In this letter, we introduce a theoretical framework for constructing hardware-tailored (HT) diagonalization circuits. We apply our framework to group the Pauli operators occurring in the decomposition of a given Hamiltonian into jointly-HT-diagonalizable sets. We investigate several classes of popular Hamiltonians and observe that our approach requires a smaller number of measurements than conventional TPB approaches. Finally, we experimentally demonstrate the practical applicability of our technique, which showcases the great potential of our circuits for near-term quantum computing.

In this era of noisy intermediate scale quantum devices, variational quantum algorithms show promise as an avenue for quantum advantage. The performance of such approaches for specific quantum applications is closely coupled to the details of the quantum hardware with respect to the noise levels and the variational quantum circuit. To achieve optimal performance, the choice of variational quantum circuit architecture should therefore be informed by both the hardware details as well as the goal of the application. In other words, co-design of quantum applications for their specific hardware and at all levels of the quantum computing stack should be explored to achieve optimal performance. In this work, we propose a reinforcement learning algorithm that co-designs noise resilient quantum circuits and qubit mappings based on the knowledge of chemistry problems, quantum architectures and noise models. To …

The first evidence for X (3872) production in relativistic heavy ion collisions is reported. The X (3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of s NN= 5.02 TeV per nucleon pair, using the decay chain X (3872)→ J/ψ π+ π−→ μ+ μ− π+ π−. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7 nb− 1. The measurement is performed in the rapidity and transverse momentum ranges| y|< 1.6 and 15< p T< 50 GeV/c. The significance of the inclusive X (3872) signal is 4.2 standard deviations. The prompt X (3872) to ψ 2 S yield ratio is found to be ρ Pb− Pb= 1.08±0.49 (stat)±0.52 (syst), to be compared with typical values of 0.1 for p p collisions. This result provides a unique experimental input to theoretical models of the X (3872) production mechanism, and of the nature of this exotic state.

Informationally complete (IC) positive operator-valued measures (POVMs) are generalized quantum measurements that offer advantages over the standard computational basis readout of qubits. For instance, IC-POVMs enable efficient extraction of operator expectation values, a crucial step in many quantum algorithms. POVM measurements are typically implemented by coupling one additional ancilla qubit to each logical qubit, thus imposing high demands on the device size and connectivity. Here, we show how to implement a general class of IC-POVMs without ancilla qubits. We exploit the higher-dimensional Hilbert space of a qudit in which qubits are often encoded. POVMs can then be realized by coupling each qubit to two of the available qudit states, followed by a projective measurement. We develop the required control pulse sequences and numerically establish their feasibility for superconducting …

A search for the exotic decay of the Higgs boson (H) into a b resonance plus missing transverse momentum is described. The search is performed with the ATLAS detector at the Large Hadron Collider using 139 fb− 1 of pp collisions at= 13 TeV. The search targets events from ZH production in an NMSSM scenario where H→, with→, where a is a light pseudoscalar Higgs boson and are the two lightest neutralinos. The decay of the a boson into a pair of b-quarks results in a peak in the dijet invariant mass distribution. The final-state signature consists of two leptons, two or more jets, at least one of which is identified as originating from a b-quark, and missing transverse momentum. Observations are consistent with Standard Model expectations and upper limits are set on the product of cross section times branching ratio for a three-dimensional scan of the masses of the, and a boson.

The paper presents a measurement of the Standard Model Higgs Boson decaying to b-quark pairs in the vector boson fusion (VBF) production mode. A sample corresponding to 126  of proton–proton collision data, collected with the ATLAS experiment at the Large Hadron Collider, is analyzed utilizing an adversarial neural network for event classification. The signal strength, defined as the ratio of the measured signal yield to that predicted by the Standard Model for VBF Higgs production, is measured to be , corresponding to an observed (expected) significance of 2.6 (2.8) standard deviations from the background only hypothesis. The results are additionally combined with an analysis of Higgs bosons decaying to b-quarks, produced via VBF in association with a photon.