Superconducting coplanar waveguide(CPW) can be widely used as two-dimensional(2 D) resonator, transmission line or feedline, providing an important component for superconducting quantum circuit which is a promisin...Superconducting coplanar waveguide(CPW) can be widely used as two-dimensional(2 D) resonator, transmission line or feedline, providing an important component for superconducting quantum circuit which is a promising candidate for quantum information processing. Due to the discontinuities and asymmetries in the ground planes, CPW usually exhibits the spurious resonance, which is a common source of decoherence in circuit quantum electrodynamics experiments. To mitigate the spurious resonance, we fabricated superconducting aluminum air-bridges on Nb CPW. The fabricated airbridges are approximately 3 m high and up to 120 m long. Compared with other methods, the fabrication procedures of our air-bridges are simpler, and the air-bridge can withstand strong ultrasound.展开更多
A compact acquisition system developed for a flexible large area monoport tactile surface is presented in this paper. This sensor requires a single port connection and avoids complicated matrix acquisition system and ...A compact acquisition system developed for a flexible large area monoport tactile surface is presented in this paper. This sensor requires a single port connection and avoids complicated matrix acquisition system and multiplexing. The tactile surface is based on a coplanar transmission line printed on a large area flexible substrate. Touching the waveguide generates a reflected signal. A harmonic analysis of this reflected signal at the line input port allows locating the touch event. A compact and low complexity acquisition system has been developed in order to demonstrate the principle and evaluate the feasibility of its integration on the sensor. Theoretical background, design and measurements on the overall sensor are exposed. The acquisition circuit imperfections have been demonstrated experimentally and correction methods have been proposed and implemented. Results are presented, and to assess the precision of the compact acquisition system, they are compared to reference measurements made with a Vector Network Analyzer.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFA0301802)the National Natural Science Foundation of China(Grant Nos.11474152,11274156,11504165,and 61521001)
文摘Superconducting coplanar waveguide(CPW) can be widely used as two-dimensional(2 D) resonator, transmission line or feedline, providing an important component for superconducting quantum circuit which is a promising candidate for quantum information processing. Due to the discontinuities and asymmetries in the ground planes, CPW usually exhibits the spurious resonance, which is a common source of decoherence in circuit quantum electrodynamics experiments. To mitigate the spurious resonance, we fabricated superconducting aluminum air-bridges on Nb CPW. The fabricated airbridges are approximately 3 m high and up to 120 m long. Compared with other methods, the fabrication procedures of our air-bridges are simpler, and the air-bridge can withstand strong ultrasound.
文摘A compact acquisition system developed for a flexible large area monoport tactile surface is presented in this paper. This sensor requires a single port connection and avoids complicated matrix acquisition system and multiplexing. The tactile surface is based on a coplanar transmission line printed on a large area flexible substrate. Touching the waveguide generates a reflected signal. A harmonic analysis of this reflected signal at the line input port allows locating the touch event. A compact and low complexity acquisition system has been developed in order to demonstrate the principle and evaluate the feasibility of its integration on the sensor. Theoretical background, design and measurements on the overall sensor are exposed. The acquisition circuit imperfections have been demonstrated experimentally and correction methods have been proposed and implemented. Results are presented, and to assess the precision of the compact acquisition system, they are compared to reference measurements made with a Vector Network Analyzer.