Method of Surgical Treatment of Spine Injury with the Use of Extracorporeal Navigation System Based on Additive Technologies.

We present a method of minimally invasive transcutaneous insertion of screws using a prefabricated extracorporeal navigation system using additive technologies (based on primary data obtained from the DICOM package in multi-detector computed tomography of the affected spine segment) according to the principle of personalized medicine. The method was tested on 10 dogs of different breeds with generally similar mechanism of trauma and typical consequences that led to fracture and dislocation of one of the lumbar vertebrae. In all animals, a positive treatment outcome of different degrees was achieved. Regression of the neurological deficit without significant postoperative inflammatory reaction was noted. The proposed method of treatment reduces the risk of malposition in pedicular and interbody pins and reduces radiation intraoperative exposure.

Quantum Rabi Oscillations in Coherent and in Mesoscopic Cat Field States.

The simple resonant Rabi oscillation of a two-level system in a single-mode coherent field reveals complex features at the mesoscopic scale, with oscillation collapses and revivals. Using slow circular Rydberg atoms interacting with a superconducting microwave cavity, we explore this phenomenon in an unprecedented range of interaction times and photon numbers. We demonstrate the efficient production of cat states, which are the quantum superposition of coherent components with nearly opposite phases and sizes in the range of few tens of photons. We measure cuts of their Wigner functions revealing their quantum coherence and observe their fast decoherence. This experiment opens promising perspectives for the rapid generation and manipulation of nonclassical states in cavity and circuit quantum electrodynamics.

Benchmarking Maximum-Likelihood State Estimation with an Entangled Two-Cavity State.

The efficient quantum state reconstruction algorithm described by Six et al. [Phys. Rev. A 93, 012109 (2016)PLRAAN2469-992610.1103/PhysRevA.93.012109] is experimentally implemented on the nonlocal state of two microwave cavities entangled by a circular Rydberg atom. We use information provided by long sequences of measurements performed by resonant and dispersive probe atoms over timescales involving the system decoherence. Moreover, we benefit from the consolidation, in the same reconstruction, of different measurement protocols providing complementary information. Finally, we obtain realistic error bars for the matrix elements of the reconstructed density operator. These results demonstrate the pertinence and precision of the method, directly applicable to any complex quantum system.

Field locked to a Fock state by quantum feedback with single photon corrections.

Fock states with photon numbers n up to 7 are prepared on demand in a microwave superconducting cavity by a quantum feedback procedure that reverses decoherence-induced quantum jumps. Circular Rydberg atoms are used as quantum nondemolition sensors or as single-photon emitter or absorber actuators. The quantum nature of these actuators matches the correction of single-photon quantum jumps due to relaxation. The flexibility of this method is suited to the generation of arbitrary sequences of Fock states.

Phase space tweezers for tailoring cavity fields by quantum Zeno dynamics.

We discuss an implementation of quantum Zeno dynamics in a cavity quantum electrodynamics experiment. By performing repeated unitary operations on atoms coupled to the field, we restrict the field evolution in chosen subspaces of the total Hilbert space. This procedure leads to promising methods for tailoring nonclassical states. We propose to realize "tweezers" picking a coherent field at a point in phase space and moving it towards an arbitrary final position without affecting other nonoverlapping coherent components. These effects could be observed with a state-of-the-art apparatus.

Process tomography of field damping and measurement of Fock state lifetimes by quantum nondemolition photon counting in a cavity.

The relaxation of a quantum field stored in a high-Q superconducting cavity is monitored by nonresonant Rydberg atoms. The field, subjected to repetitive quantum nondemolition photon counting, undergoes jumps between photon number states. We select ensembles of field realizations evolving from a given Fock state and reconstruct the subsequent evolution of their photon number distributions. We realize in this way a tomography of the photon number relaxation process yielding all the jump rates between Fock states. The damping rates of the n photon states (0 < or = n < or = 7) are found to increase linearly with n. The results are in excellent agreement with theory including a small thermal contribution.

Freezing coherent field growth in a cavity by the quantum zeno effect.

We have frozen the coherent evolution of a field in a cavity by repeated measurements of its photon number. We use circular Rydberg atoms dispersively coupled to the cavity mode for an absorption-free photon counting. These measurements inhibit the growth of a field injected in the cavity by a classical source. This manifestation of the quantum Zeno effect illustrates the backaction of the photon number determination onto the field phase. The residual growth of the field can be seen as a random walk of its amplitude in the two-dimensional phase space. This experiment sheds light onto the measurement process and opens perspectives for active quantum feedback.

Inserting two atoms into a single optical micropotential.

We recently demonstrated that strings of trapped atoms inside a standing wave optical dipole trap can be rearranged using optical tweezers [Y. Miroshnychenko, Nature 442, 151 (2006)]. This technique allows us to actively set the interatomic separations on the scale of the individual trapping potential wells. Here, we use such a distance-control operation to insert two atoms into the same potential well. The detected success rate of this manipulation is 16(-3)(+4)%, in agreement with the predictions of a theoretical model based on our experimental parameters.

Submicrometer position control of single trapped neutral atoms.

We optically detect the positions of single neutral cesium atoms stored in a standing wave dipole trap with a subwavelength resolution of 143 nm rms. The distance between two simultaneously trapped atoms is measured with an even higher precision of 36 nm rms. We resolve the discreteness of the interatomic distances due to the 532 nm spatial period of the standing wave potential and infer the exact number of trapping potential wells separating the atoms. Finally, combining an initial position detection with a controlled transport, we place single atoms at a predetermined position along the trap axis to within 300 nm rms.

Neutral atom quantum register.

We demonstrate the realization of a quantum register using a string of single neutral atoms which are trapped in an optical dipole trap. The atoms are selectively and coherently manipulated in a magnetic field gradient using microwave radiation. Our addressing scheme operates with a high spatial resolution, and qubit rotations on individual atoms are performed with 99% contrast. In a final readout operation we analyze each individual atomic state. Finally, we have measured the coherence time and identified the predominant dephasing mechanism for our register.

Coherence properties and quantum state transportation in an optical conveyor belt.

We have prepared and detected quantum coherences of trapped cesium atoms with long dephasing times. Controlled transport by an "optical conveyor belt" over macroscopic distances preserves the atomic coherence with slight reduction of coherence time. The limiting dephasing effects are experimentally identified, and we present an analytical model of the reversible and irreversible dephasing mechanisms. Our experimental methods are applicable at the single-atom level. Coherent quantum bit operations along with quantum state transport open the route towards a "quantum shift register" of individual neutral atoms.

Continued imaging of the transport of a single neutral atom.

We have continuously imaged the controlled motion of a single atom as well as of a small number of distinguishable atoms with observation times exceeding one minute. The Cesium atoms are confined to potential wells of a standing wave optical dipole trap which allows to transport them over macroscopic distances. The atoms are imaged by an intensified CCD camera, and spatial resolution near the diffraction limit is obtained.

[Outpatient treatment and follow-up of adolescents and adults with mucoviscidosis in a specialized center]. / Opyt dispansernogo nabliudeniia i ambulatornogo lecheniia podrostkov i vzroslykh mukovistziodozom v usloviiakh spetsializirovannogo tsentra.

Of 49 mucoviscidosis patients benefited more those who received adequate home care. These patients had only 1-2 episodes of pulmonary inflammation aggravation a year, remained socially active, avoided hospitalization. It is emphasized that such patients need continuous follow-up and check-ups.