Coherent manipulation of Andreev states in superconducting atomic contacts.

Coherent control of quantum states has been demonstrated in a variety of superconducting devices. In all of these devices, the variables that are manipulated are collective electromagnetic degrees of freedom: charge, superconducting phase, or flux. Here we demonstrate the coherent manipulation of a quantum system based on Andreev bound states, which are microscopic quasi-particle states inherent to superconducting weak links. Using a circuit quantum electrodynamics setup, we performed single-shot readout of this Andreev qubit. We determined its excited-state lifetime and coherence time to be in the microsecond range. Quantum jumps and parity switchings were observed in continuous measurements. In addition to having possible quantum information applications, such Andreev qubits are a test-bed for the physics of single elementary excitations in superconductors.

Superconducting atomic contacts inductively coupled to a microwave resonator.

We describe and characterize a microwave setup to probe the Andreev levels of a superconducting atomic contact. The contact is part of a superconducting loop inductively coupled to a superconducting coplanar resonator. By monitoring the resonator reflection coefficient close to its resonance frequency as a function of both flux through the loop and frequency of a second tone we perform spectroscopy of the transition between two Andreev levels of highly transmitting channels of the contact. The results indicate how to perform coherent manipulation of these states.

Neonatal cleft lip repair: the anesthesiologist's point of view.

Neonatal cleft lip repair is no longer an unusual procedure and several series have been published to date. We present our 3-year experience from the anesthesiologist's point of view. Preoperative evaluation, perioperative management, and postoperative problems are described. A thorough preoperative evaluation in order to exclude associated malformations (especially cardiac) and experience in neonatal anesthesia are essential for the sake of safety.

Traumatic tracheo-bronchial ruptures.

A series of 18 ruptures of trachea or bronchi is reported. Gaseous semiology is predominant (pneumomediastinum and subcutaneous emphysema 72%, pneumothorax 67%). Haemoptysis is present in 28%. Assessment of the diagnosis and localization of the rupture was obtained through rigid bronchoscopy, early in the series, and then via fiberoptic endoscopy. Ignored cases in the early phase manifested themselves lately by atelectatic phenomena. Tracheal ruptures (5) were treated by direct repair (1/5) or tracheostomy (3/5) ; 1 died before surgery. Bronchial ruptures (13) were submitted to bronchoplastic procedures (7/13) or pulmonary resection (4/13). In 2 cases, no surgery was necessary or possible. Mortality (7/18) is linked with the importance of associated lesions, especially neurological ones.

[Traumatic subcutaneous ruptures of the cervical trachea (author's transl)]. / Les ruptures traumatiques sous-tégumentaires de la trachée cervicale.

Traumatic subcutaneous rupture of the cervical trachea is a rare but serious lesion that may cause death of the patient. Few cases come to treatment. This lesion results from a contusion to the anterior neck during hyperextension. It consists in a straight transection between larynx and trachea or between one of the 4 first tracheal rings, and is usually associated to multiple trauma involving the chest and head. Specific symptoms are often blurred by those of the associated lesions making diagnosis complex. This should ideally be confirmed by endoscopy or, if not feasable by cervicotomy. Emergency treatment is directed to restablishment of an adequate ventilation. Direct anastomosis by separate resorbable sutures yields excellent long-term results without stenosis. Creation of a transitory tracheotomy, when commanded by regional atresion, sometimes induces late stenosis; secondary repair is then less favorable. The rate of definitive recurrent nerve paralysis is high. There are also frequent distortions of the vocal cords with modifications of the voice and transitory palsy of the phrenic nerve. The authors draw these conclusions from one personal case and from the literature.