New, highly specific and sensitive analytical methodology has been applied to the determination of chlorinated dibenzo- p -dioxins in particulate matter. The results show that dioxins are present particles from many types combustion sources dust soil vicinity sources. data indicate may occur matter most organic material, suggest hypothesis result trace chemical reactions occurring fire.

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 operator expectation values, a crucial step in many algorithms. POVM typically implemented by coupling one additional ancilla qubit to each logical qubit, thus imposing high demands on device size and connectivity. Here, we show how implement general class...

The compass model on a square lattice provides natural template for building subsystem stabilizer codes. surface code and the Bacon-Shor represent two extremes of possible codes depending how many gauge qubits are fixed. We explore threshold behavior in this broad class local by trading locality asymmetry degrees freedom syndrome information. analyze these with asymmetric spatially inhomogeneous Pauli noise capacity phenomenological models. In idealized settings, we observe considerably...

Abstract A central building block of many quantum algorithms is the diagonalization Pauli operators. Although it always possible to construct a circuit that simultaneously diagonalizes given set commuting operators, only resource-efficient circuits can be executed reliably on near-term computers. Generic circuits, in contrast, often lead an unaffordable SWAP gate overhead devices with limited hardware connectivity. common alternative exclude two-qubit gates altogether. However, this comes at...

A Bacon-Shor code is a subsystem quantum error-correcting on an $L\ifmmode\times\else\texttimes\fi{}L$ lattice where the $2(L\ensuremath{-}1)$ weight-$2L$ stabilizers are usually inferred from measurements of $2L(L\ensuremath{-}1)$ weight-2 gauge operators. Here, we show that can be measured directly and fault tolerantly with bare ancillary qubits by constructing circuits follow pattern We then examine implications this method for small codes comparing distance-3 versions rotated surface...

It is important for performance studies in quantum technologies to analyze circuits the presence of noise. We introduce an error probability tensor, a tool track generalized Pauli statistics qudits within composed qudit Clifford gates. Our framework compatible with stabilizer error-correcting codes. show how tensor can be applied most general case, and we demonstrate analysis bipartite repeaters correction. provide exact analytical solution state distributed by such repeater. For fixed...

The authors theoretically analyze the performance of long-distance quantum communication protocols, specifically repeaters based on Gottesman-Kitaev-Preskill (GKP) qudits. Previously, only qubit case has been studied. They construct three repeater schemes and find that, while in most cases any benefits using higher dimensions is negated by worse error correction, there are some regimes where use qubits does increase secret key rate.

How much noise can a given quantum state tolerate without losing its entanglement? For qudits of arbitrary dimension, I investigate this question for two models: Global white noise, where depolarizing channel is applied to all simultaneously, and local single qudit every individually. Using unitary generalization the Pauli group, derive thresholds stabilizer states, with an emphasis on graph compare different entanglement criteria. The PPT reduction criteria generally provide high...

A central building block of many quantum algorithms is the diagonalization Pauli operators. Although it always possible to construct a circuit that simultaneously diagonalizes given set commuting operators, only resource-efficient circuits are reliably executable on near-term computers. Generic can lead an unaffordable Swap-gate overhead devices with limited hardware connectivity. common alternative excluding two-qubit gates, however, this comes at cost restricting class diagonalizable sets...

A potential quantum internet would open up the possibility of realizing numerous new applications, including provably secure communication. Since losses photons limit long-distance, direct communication and widespread networks, repeaters are needed. The so-called PLOB-repeaterless bound [Pirandola et al., Nat. Commun. 8, 15043 (2017)] is a fundamental on capacity Here, we analytically derive quantum-repeater gain for error-corrected, one-way based higher-dimensional qudits two different...

The Gottesman-Kitaev-Preskill (GKP) code offers the possibility to encode higher-dimensional qudits into individual bosonic modes with, for instance, photonic excitations. Since photons enable reliable transmission of quantum information over long distances and since GKP states subject photon loss can be recovered some extent, has found recent applications in theoretical investigations communication protocols. While previous studies have primarily focused on qubits, possible practical...

In this Comment we discuss the device-independent conference key agreement (DICKA) protocol [Phys. Rev. A 97, 022307 (2018)]. We show that suggested honest implementation fails, because perfectly correlated measurement results and required Bell-inequality violation cannot be achieved simultaneously, in contradiction to what is claimed. further via semidefinite programming there exist any suitable tripartite setting, rendering DICKA incomplete.

The Shor-Laflamme distribution (SLD) of a quantum state is collection local unitary invariants that quantify $k$-body correlations. We show the SLD graph states can be derived by solving graph-theoretical problem. In this way, mean and variance are obtained as simple functions efficiently computable properties. Furthermore, formulation enables us to derive closed expressions SLDs for some families. For cluster states, we observe very similar binomial distribution, argue property typical in...

Fathoming out quantum state space is a challenging endeavor due to its exponentially growing dimensionality. At the expense of being bound in expressiveness, discrete and finite subspace graph states easier investigate via pictorial framework accompanied with theoretical toolkit from stabilizer formalism. Analyzing hand-drawn graphs tedious time-consuming task imposes limitations problem sizes that can be addressed. Similarly, algorithmic studies using adjacency matrices alone lack benefit...

Recent face recognition experiments on a major benchmark LFW show stunning performance--a number of algorithms achieve near to perfect score, surpassing human rates. In this paper, we advocate evaluations at the million scale (LFW includes only 13K photos 5K people). To end, have assembled MegaFace dataset and created first challenge. Our One Million that capture more than 690K different individuals. The challenge evaluates performance with increasing numbers distractors (going from 10 1M)...

The scaling of high density NOR Flash memory devices with multi level cell (MLC) hits the reliability break wall because relatively intrinsic bit error rate (IBER). chip maker companies offer two solutions to meet output (OBER) specification: either partial coverage correction code (ECC) or data storage in single (SLC) significant increase die cost. flash allows write information small portions, therefore full protection becomes costly due required redundancy, e.g. $\sim$50%. This is very...

e16295 Background: Adjuvant chemotherapy improves survival following resection of pancreatic ductal adenocarcinoma (PDAC). A modified fluorouracil/irinotecan/oxaliplatin regimen (mFOLFIRINOX) has demonstrated improved disease free and overall survival, though gemcitabine-based monotherapy gemcitabine plus capecitabine are alternatives in less fit patients. Though there several proposed biomarkers to guide treatment decisions (GATA6, hENT1, GemPred), no biomarker is used selection clinical...

In each of the two experiments, nine rats were trained for 64 trials (eight per day) to determine if they could acquire a two-choice discrimination based on specified discriminative stimulus (S(D)). one experiment, S(D) was change in ambient illumination, while second experiment combination sinusoidal 60 Hz and static magnetic field (MF) any cues attendant energizing coils that produced MF exposure. The had illuminance as learned task easily, P <.001, whereas having MFs did not.

In this paper, we develop a general-use autonomous control strategy for managing the trade-off between processing throughput and power consumption in data centers. This approach relies on concept that delay completing computational tasks can be reduced at cost of more power. The scheme's generality allows it to applied multiple hierarchical levels within center, or another system with similar architecture. particular, show our scheme converges asynchronously unique solution. property...