15 research outputs found
Backaction noise produced via cavity-aided nondemolition measurement of an atomic clock state
We use a quantum nondemolition measurement to probe the collective pseudospin
of an atomic ensemble in a high-finesse optical cavity. We analyze the
backaction antisqueezing produced by the measurement process to show that our
protocol could create conditional spin squeezing in the atomic ensemble.Comment: 4.1 pages, 3 figure
Error Compensation of Single-Qubit Gates in a Surface Electrode Ion Trap Using Composite Pulses
The fidelity of laser-driven quantum logic operations on trapped ion qubits
tend to be lower than microwave-driven logic operations due to the difficulty
of stabilizing the driving fields at the ion location. Through stabilization of
the driving optical fields and use of composite pulse sequences, we demonstrate
high fidelity single-qubit gates for the hyperfine qubit of a
ion trapped in a microfabricated surface electrode ion
trap. Gate error is characterized using a randomized benchmarking protocol, and
an average error per randomized Clifford group gate of is
measured. We also report experimental realization of palindromic pulse
sequences that scale efficiently in sequence length
Feasibility of diaphragm pacing in patients after bilateral lung transplantation
Recent animal studies and intraoperative studies in humans suggested that phrenic nerve stimulation could attenuate ventilator-induced diaphragm dysfunction. The purpose of the present study is to examine the safety and feasibility of diaphragm pacing during the weaning process after bilateral lung transplantation. Four patients, suffering from chronic pulmonary disease, were included, and diaphragm pacing was evaluated after lung transplantation. Implantation of electrodes at the end of the lung transplant procedure was possible in three of the four patients. In all implanted patients, stimulation of the diaphragm could trigger the ventilator. Implanted electrodes were completely removed by percutaneous retraction after up to 7Â days of pacing. Adverse events related to pacing included occurrence of pain. Diaphragm pacing with temporary electrodes, inserted during surgery, is feasible and is able to trigger the ventilator in patients after bilateral lung transplantation. The use of intradiaphragmatic electrodes creates the additional opportunity to monitor the evolution of diaphragm electromyography during the postoperative weaning process.status: publishe