Quantum state tomography is an important tool in quantum information science for complete characterization of multiqubit states and their correlations. Here we report a method to perform a joint simultaneous readout of two superconducting qubits dispersively coupled to the same mode of a microwave transmission line resonator. The nonlinear dependence of the resonator transmission on the qubit s...

We report on Kerr nonlinearity and dispersive optical bistability of a Fabry-Perot optical resonator due to the displacement of ultracold atoms trapped within. In the driven resonator, such collective motion is induced by optical forces acting upon up to 10(5) 87Rb atoms prepared in the lowest band of a one-dimensional intracavity optical lattice. The longevity of atomic motional coherence allo...

We describe a resonator-based optical gyroscope whose sensitivity for measuring absolute rotation is enhanced via use of the anomalous dispersion characteristic of superluminal light propagation. The enhancement is given by the inverse of the group index, saturating to a bound determined by the group velocity dispersion. We also show how the offsetting effect of the concomitant broadening of th...

A recently developed technique for the system–and–bath quantization of open optical cavities is applied to three resonator geometries: A one dimensional dielectric, a Fabry–Perot resonator, and a dielectric disk. The system–and–bath Hamiltonian for these geometries is derived starting from Maxwell's equations and employed to compute the electromagnetic fields, the resonances, and the cavity gai...

Quantum state control including entanglement, and readout of the Josephson persistent-current qubit, flux qubit, are reviewed. First, we mention our single-shot readout of quantum superposition state of a flux qubit by a current biased dc-SQUID. Second, we mention entangled state and vacuum Rabi oscillations of a flux-qubit LC-resonator system where qubit-resonator coupled state are controlled ...

We demonstrate a total charge parity measurement by detecting the radio frequency signal that is reflected by a lumped-element resonator coupled to a single InAs nanowire double quantum dot. The high frequency response of the circuit is used to probe the effects of the Pauli exclusion principle at interdot charge transitions. Even parity charge transitions show a striking magnetic field depende...

We experimentally realize a Fabry-Perot-type optical microresonator near the cesium D2 line wavelength based on a tapered optical fiber, equipped with two fiber Bragg gratings that enclose a subwavelength diameter waist. Owing to the very low taper losses, the finesse of the resonator reaches F=86 while the on-resonance transmission is T=11%. The characteristics of our resonator fulfill the req...

Two types of compact microwave plasma ion sources (MWPIS) for focused ion beam (FIB) have been developed. Cavity resonator type plasma ion source is subjected to make resonant electric field in order to ignite plasma efficiently. The optimum length of resonator and antenna, and position of quartz and antenna have been designed by both simple calculation and computer simulation. The other source...

A Dielectric Resonator loaded Substrate integrated waveguide cavity backed slot antenna (SIDRA) is proposed for two slot polarizations and orientation. A SIW-fed cylindrical DRA using rectangular slot is used for obtaining bandwidth of about 5% at 6.15 GHz. For enhancing bandwidth, a plus shaped slot with bandwidth of about 8.80% and gain of 3.7 dB is proposed. The proposed antenna represents S...

We present the characterization of the recently developed cavity enhanced amplitude modulation laser absorption spectroscopy (CEAMLAS) technique to measure dissipation within the evanescent field of a whispering-gallery mode resonator, and demonstrate the parallel use of CEAMLAS and the Pound-Drever-Hall measurement techniques to provide both dissipation and dispersive real-time microresonator ...