Features of the Pulsed Treatment of Silicon Layers Implanted with Erbium Ions

Abstract—The formation of thin-film solid solutions of erbium in silicon and synthesis of erbium silicides were performed using continuous implantation of silicon with erbium ions followed by pulsed ion-beam treat- ment. Structural and optical properties of formed Si:Er layers were studied by Rutherford backscattering, trans- mission electron microscopy, and low-temperature photoluminescence. The dependences of erbium redistribu- tion, the microstructure of Si:Er layers, and their photoluminescence in the near-IR region on the erbium con- centration and pulsed treatment conditions were determined

Luminescence of sapphire single crystals irradiated with high-power ion beams

Optical absorption, photo- and cathodoluminescence of a sapphire single crystal (α-Al 2 O 3 ) exposed to pulsed nanosecond radiation with high-power ion beams C + /H + with an energy of 300 keV and energy density 0.5-1.5 J/cm 2 were first investigated in this work. It was found that under ion irradiation accompanied by heating of sapphire up to melting, the formation of F-type centers and their aggregates associated with oxygen vacancies was observed in the crystals under study. These centers have luminescence bands at 330, 410 and 500 nm which depend on the type and wavelength of the optical excitation. The appearance of a new PL emission at 435 nm, presumably associated with a complex vacancy-impurity defect, was also observed in the photoluminescence spectra. © Published under licence by IOP Publishing Ltd.The work was supported by the initiative scientific project № 16.5186.2017/8.9 of the Ministry of Education and Science of the Russian Federation. Experiments on ion irradiation of sapphire was done at the KIPT as a part of the state task

Antithrombotic Therapy in Patients with Paroxysmal Atrial Fibrillation after Catheter Treatment

Aim. To study the efficacy and safety of antithrombotic therapy in patients with paroxysmal atrial fibrillation (AF) after catheter treatment during 36 months of follow-up.Material and methods. The retrospective observational study included 592 patients (283 men) who underwent catheter treatment of AF, aged 26 to 86 years (median age was 61.0 [55; 67]) with paroxysmal AF, treated in cardiac arrhythmias department of the Institute of Cardiology of Tomsk National Research Medical Center from 01.01.2017 to 31.12.2019. All patients were retrospectively divided into 2 groups: the first group consisted of patients with effective AF ablation, the second - with ineffective AF ablation. During follow-up after 12, 24 and 36 months, patients' complaints, documented arrhythmia recurrences, adherence to the prescribed treatment, and adverse clinical events were taken into account.Results. In patients with paroxysmal AF, the effectiveness of catheter treatment was 73.1% after 12 months of follow-up, 69.3% – after 24 months, 71.6% – after 36 months. The analysis of our data showed that during the follow-up period of 36 months, the incidence of ischemic stroke against the background of anticoagulant therapy and effective catheter treatment of paroxysmal AF was significantly lower than in patients with unsuccessful ablation (0.3% (n=1) and 3.7% (n=4), respectively), even despite the fact that not all patients from the first group received prescribed medication.Conclusion. The use of anticoagulant therapy in patients with paroxysmal AF after interventional treatment is safe, since the invasive strategy in combination with anticoagulant therapy does not increase the risk of major and minor bleeding, and in the case of effective intervention allows statistically significantly reduce the risk of ischemic stroke and almost completely eliminate the likelihood of other thromboemolic complications

Temporal Coherence of Photons Emitted by Single Nitrogen-Vacancy Defect Centers in Diamond Using Optical Rabi-Oscillations

Photon interference among distant quantum emitters is a promising method to generate large scale quantum networks. Interference is best achieved when photons show long coherence times. For the nitrogen-vacancy defect center in diamond we measure the coherence times of photons via optically induced Rabi oscillations. Experiments reveal a close to Fourier-transform (i.e., lifetime) limited width of photons emitted even when averaged over minutes. The projected contrast of two-photon interference (0.8) is high enough to envisage applications in quantum information processing. We report 12 and 7.8 ns excited state lifetimes depending on the spin state of the defect.4 page(s

Demonstration of entanglement-by-measurement of solid state qubits

Projective measurements are a powerful tool for manipulating quantum states. In particular, a set of qubits can be entangled by measurement of a joint property such as qubit parity. These joint measurements do not require a direct interaction between qubits and therefore provide a unique resource for quantum information processing with well-isolated qubits. Numerous schemes for entanglement-by-measurement of solid-state qubits have been proposed, but the demanding experimental requirements have so far hindered implementations. Here we realize a two-qubit parity measurement on nuclear spins in diamond by exploiting the electron spin of a nitrogen-vacancy center as readout ancilla. The measurement enables us to project the initially uncorrelated nuclear spins into maximally entangled states. By combining this entanglement with high-fidelity single-shot readout we demonstrate the first violation of Bells inequality with solid-state spins. These results open the door to a new class of experiments in which projective measurements are used to create, protect and manipulate entanglement between solid-state qubits.Comment: 6 pages, 4 figure

Properties of the barium strontium titanate film on the silicon substrate

The reported study was supported of the Russian Foundation for Basic Research, research project No. 18-42-160005. The work is partially performed according to the Russian Government Program of Competitive Growth of Kazan Federal University. A.S. Elshin thanks the Russian Foundation for Basic Research for financial support, project No. 17-32-50047

Influence of characteristics of epicardial adipose tissue and myocardial sympathetic innervation on the development of late recurrence of atrial fibrillation after radiofrequency ablation

Aim. To investigate the relationship between radiological characteristics of epicardial adipose tissue (EAT) and myocardial sympathetic activity, as well as to study their association with late recurrence of atrial fibrillation (AF) after radiofrequency ablation (RFA).Material and methods. This prospective study included 26 people with persistent and long-standing persistent AF scheduled for interventional AF treatment. Before the RFA procedure, all patients underwent cardiac 123I-metaiodobenzylguanidine (123I-MIBG) scintigraphy to assess the myocardial sympathetic innervation and contrast-enhanced cardiac multislice computed tomography to assess pulmonary vein anatomy, left atrial volume, and EAT volume. Clinical follow-up, including 12-lead electrocardiography (ECG) and 24-hour ECG monitoring, was carried out 3, 6 and 12 months after RFA.Results. After the end of follow-up, the patients were divided into two groups: with AF recurrence (group 1, n=8) and without AF recurrence (group 2, n=18). Multivariate logistic analysis found that only the 123I-MIBG washout rate (odds ratio, 1,0943; 95% confidence interval, 1,0138-1,1812) proved to be an independent predictor of late AF recurrence after RFA. ROC analysis revealed that a 123I-MIBG washout rate >21% with a sensitivity of 75% and a specificity of 83,3% (AUC=0,844; p<0,001) predicts late AF recurrence after RFA.Conclusion. Parameters of myocardial sympathetic activity, assessed by 123I-MIBG myocardial scintigraphy, are associated with late AF recurrence after RFA in patients with persistent and long-standing persistent AF. There were no reliable data confirming associations between myocardial sympathetic innervation and radiological EAT indicators, as well as the effect of the latter on the risk of AF recurrence after RFA