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We propose a scheme for a cavity quantum electrodynamics (QED) architecture for a current-biased superconducting flux qubit with three Josephson junctions. The qubit operation is performed by using a bias current coming from the current mode of the circuit resonator. If the phase differences of junctions are to be coupled with the bias current, the Josephson junctions should be arranged in an asymmetric way in the qubit loop. Our QED scheme provides a strong coupling between the flux qubit and the transmission line resonator of the circuit.

Constructing a fault-tolerant quantum computer is a daunting task. Given any design, it is possible to determine the maximum error rate of each type of component that can be tolerated while still permitting arbitrarily large-scale quantum computation. It is an underappreciated fact that including an appropriately designed mechanism enabling long-range qubit coupling or transport substantially increases the maximum tolerable error rates of all components. With this thought in mind, we take the superconducting flux qubit coupling mechanism described in PRB 70, 140501 (2004) and extend it to allow approximately 500 MHz coupling of square flux qubits, 50 um a side, at a distance of up to several mm. This mechanism is then used as the basis of two scalable architectures for flux qubits taking into account crosstalk and fault-tolerant considerations such as permitting a universal set of logical gates, parallelism, measurement and initialization, and data mobility.

We report experiments on superconducting flux qubits in a circuit quantum electrodynamics (cQED) setup. Two qubits, independently biased and controlled, are coupled to a coplanar waveguide resonator. Dispersive qubit state readout reaches a maximum contrast of $72\,\%$. We find intrinsic energy relaxation times at the symmetry point of $7\,\mu\text{s}$ and $20\,\mu\text{s}$ and levels of flux noise of $2.6\,\mu \Phi_0/\sqrt{\text{Hz}}$ and $2.7\,\mu \Phi_0/\sqrt{\text{Hz}}$ at 1 Hz for the two qubits. We discuss the origin of decoherence in the measured devices. These results demonstrate the potential of cQED as a platform for fundamental investigations of decoherence and quantum dynamics of flux qubits.

This project was designed to accomplish a systematic study of the mass-transfer behavior of chlorinated-solvent immiscible liquids in heterogeneous porous media at multiple scales, and to investigate the impact of source-zone architecture on mass discharge and plume response. The project involved both bench-scale and field-scale investigations, as well as mathematical modeling analysis. A unique component of the project involved comprehensive long-term studies conducted at a field site (the TIAA site). The analyses employed contaminant mass discharge as an integrative measure of the performance and effectiveness of remediation efforts. The standard approach of characterizing discharge at the source-zone scale was expanded to provide characterization at the plume scale, which was evaluated by examining the change in contaminant mass discharge associated with plume-scale pump-and-treat systems. This approach allows linking the impacts of source-zone remediation to effects on site-wide risk. The studies reported herein investigated the impact of source-zone remediation efforts on contaminant mass discharge and associated plume response at an unprecedented resolution and scale. The results obtained thus provide a significant, unique contribution to our understanding of source-zone dynamics and plume persistence for DNAPL sites. It is anticipated that application of the concepts and tools developed from the project to other DOD sites would provide substantial benefits, including improving the assessment and cost-effective operation of remediation systems for, and enhancing long-term management of, sites contaminated by chlorinated solvents.

We theoretically study a circuit quantum electrodynamics (QED) architecture with current-biased flux qubits. The qubit is coupled to the transmission line resonator by a bias current originating from the current mode of the resonator. Ultrastrong coupling regime can be obtained by varying the capacitance between the qubit and the resonator. We propose a scalable design for the circuit QED with current-biased flux qubits, where the dc-SQUIDs take the role of switching the qubit-resonator coupling. An exact calculation on two-qubit coupling strength in the scalable design shows the transition from ferromagnetic to antiferromagnetic xy-type interaction.

Through a combination of laser beams, we engineer a two-dimensional optical lattice of Mexican hat potentials able to host atoms in its ring-shaped wells. When tunneling can be ignored (at high laser intensities), we show that a well-defined qubit can be associated to atoms trapped in each of the rings. Each of these two-level systems can be manipulated by a suitable configuration of Raman laser beams imprinting a synthetic flux onto each Mexican hat cell of the lattice. Overall, the system forms a scalable architecture for Atomtronics flux qubits.

The deteriorating environmental system and increasing number of time-varying datasets have generated a significant demand for new techniques to support online high-efficiency climate analysis. In response to this demand, this paper introduces an innovative multilayer architecture driven by a tile service in a virtual globe environment. This architecture is supported by the open-source and highly efficient osgEarth virtual globe. In addition, we develop a gSoap-based tile service to address the challenges of visualizing and analysing massive data under hardware restrictions conditions. The service contains a lossless pyramid tile set that can automatically provide tiles with proper accuracy according to the demands of users under different conditions. Furthermore, we add a hybrid database file system to the service for high availability. This service is then applied for estimation of ocean carbon flux. And a proof-of-concept prototype, SatCO2, has been developed to demonstrate the feasibility and performance of the proposed architecture.