NMR Studies of Field Induced Magnetism in CeCoIn5_5

Recent Nuclear Magnetic Resonance and elastic neutron scattering experiments have revealed conclusively the presence of static incommensurate magnetism in the field-induced B phase of CeCoIn5. We analyze the NMR data assuming the hyperfine coupling to the In(2) nuclei is anisotropic and simulate the spectra for several different magnetic structures. The NMR data are consistent with ordered Ce moments along the [001] direction, but are relatively insensitive to the direction of the incommensurate wavevector.Comment: 4 pages, 3 figure

Impurities near an Antiferromagnetic-Singlet Quantum Critical Point

Heavy fermion systems, and other strongly correlated electron materials, often exhibit a competition between antiferromagnetic (AF) and singlet ground states. Using exact Quantum Monte Carlo (QMC) simulations, we examine the effect of impurities in the vicinity of such AF- singlet quantum critical points, through an appropriately defined impurity susceptibility, $\chi_{imp}$. Our key finding is a connection, within a single calculational framework, between AF domains induced on the singlet side of the transition, and the behavior of the nuclear magnetic resonance (NMR) relaxation rate $1/T_1$. We show that local NMR measurements provide a diagnostic for the location of the QCP which agrees remarkably well with the vanishing of the AF order parameter and large values of $\chi_{imp}$. We connect our results with experiments on Cd-doped CeCoIn$_5$

Local edge modes in doped cuprates with checkerboard polaronic heterogeneity

We study a periodic polaronic system, which exhibits a nanoscale superlattice structure, as a model for hole-doped cuprates with checkerboard-like heterogeneity, as has been observed recently by scanning tunneling microscopy (STM). Within this model, the electronic and phononic excitations are investigated by applying an unrestricted Hartree-Fock and a random phase approximation (RPA) to a multiband Peierls-Hubbard Hamiltonian in two dimensions

Impact of disorder on dynamics and ordering in the honeycomb-lattice iridate Na2IrO3

Kitaev's honeycomb spin-liquid model and its proposed realization in materials such as α-RuCl3, Li2IrO3, and Na2IrO3 continue to present open questions about how the dynamics of a spin liquid are modified in the presence of non-Kitaev interactions as well as the presence of inhomogeneities. Here we use Na23 nuclear magnetic resonance to probe both static and dynamical magnetic properties in single-crystal Na2IrO3. We find that the NMR shift follows the bulk susceptibility above 30 K but deviates from it below; moreover below TN the spectra show a broad distribution of internal magnetic fields. Both of these results provide evidence for inequivalent magnetic sites at low temperature, suggesting inhomogeneities are important for the magnetism. The spin-lattice relaxation rate is isotropic and diverges at TN, suggesting that the Kitaev cubic axes may control the critical quantum spin fluctuations. In the ordered state, we observe gapless excitations, which may arise from site substitution, emergent defects from milder disorder, or possibly be associated with nearby quantum paramagnetic states distinct from the Kitaev spin liquid

An Application of Engineering 4.0 to Hospitalized Patients

In this paper the authors address the problem of surveillance of bedridden patients in hospitals and residences for elderly. Unfortunately, patients cannot be supervised by operators 24 h a day, given the associated costs. An attempt to solve this problem is already provided by wearable devices. This paper describes a 4.0 system implemented to overcome the limits (identified by interviewing a sample of nurses belonging to different facilities) of the wearable devices available on the market. The system proposed consists in monitoring the bed, instead of the patient, through applied sensors. By centralizing and analyzing the data collected it is possible to promptly inform the operative center of the occurrence of risky events to which bedridden patients are normally subjected. The scope of the system is preventing such risks, where possible, or mitigating their effects with a real time intervention. A case study on an active facility, conducted as a pilot project, confirms the humanitarian and economic benefits for patients and facility

Smart Inventory 4.0: Advanced version

The Authors of this paper had first conceptualized and then developed the automated picking plant described in the paper “A 4.0 Automated Warehouse Storage and Picking System for Order Fulfillment”, presented by the Authors to the WCE 2021 IAENG Congress and awarded with the “Best Paper Award of the 2021 International Conference of Manufacturing Engineering and Engineering Management”. In the perspective of the continuous improvement of Industry 4.0 they have brought to this first system the significant functional improvements object of this paper. In particular, having found that the loading of the goods in the individual boxes was carried out by the Operators in this factory by using ladders on which they climbed, without the necessary PPE and carrying the load manually, with the consequent risk of falling from such heights (3-6m) to cause even serious physical damage, the Authors first studied and then implemented an automatic loading system. A second problem was then highlighted for the storage of special products such as Food and Pharma, that, unlike what happens in the Beauty Sector (for which the plant was designed), need to remain in specific conditions of temperature and relative humidity. The paper describes how, in this new version, the two parameters are monitored in each single box by means of appropriate sensors that send alerts to the centralized control system when these parameters are outside the preset threshold. In this way, prompt remedial intervention is possible, avoiding the deterioration of the contents of the boxes and the consequent economic damage deriving from their alienation. All this is made possible at acceptable costs thanks to the technologies offered by Industry 4.0 such as modern robotics and Data Centralization via IIoT for monitoring and control

Engineering Solutions 4.0 in the fight against the spread of Covid 19 A new Methodology including processes, procedures and devices

Thanks to the principles and technologies made available by Industry 4.0, the authors conceptualized and modeled a new strategy, capable of making an effective contribution to the problem of limiting contagion from Covid19 today, and tomorrow from any possible other type virus, bacteria or pathogen agent introduced by subjects who, although unaware of being vectors, develop the infection only after their access to the places of stay (Hotel, office, Infrastructure, etc.) where they go to reside. The key point of the strategy is a 4.0 thermoscanner, created by the authors, which is positioned in appropriately chosen locations of the settlement and an innovative method of disinfection of the same implemented by means of UV-C rays and Ozone in the gaseous state, produced by a machine, also conceptualized and developed by the authors, capable of reproducing the Chapman Cycle with the associated advantages. Therefore, it is operated an absolute disinfection based on a reversible cycle Oxygen-Ozone-Oxygen, with a prompt re-habitability of the treated rooms, with minimal treatment costs and without the use of expensive and unhealthy chemicals or wet water vapor (incompatible with paper and electronics). This technology was described in the paper “Sanitizing of Confined Spaces Using Gaseous Ozone Produced by 4.0 Machines” presented by the authors to the WCE 2021 IAENG Congress and awarded with the “Best Paper Award of the 2021 International Conference of Systems Biology and Bioengineering”. In the presence of a Person with a fever, the thermoscanner automatically launches an alert to the site Safety officers, who confine him to an isolated place and make the Health Institutions intervene and take it over

Through Engineering 4.0 the Safe Operating Block for Patients and Medical Staff

The Paper deals with the management of the operating block in its many activities. By a new approach and with innovative machinery specific several problems were thus studied and overcome, such as the control of hospital infections, the operations of washing and sterilization of surgical instruments, the planning of interventions, the tracking of drugs and medical devices entering the operating block, the management of stocks, the bed management, the monitoring of environmental parameters for patient comfort and safety, the monitoring of machines and the interlocking of doors, etc. Furthermore, it is proposed a wide use of the analytical tools to support decision making, extended to the most modern Cyber-Physical Systems and Digital Twin, alongside Machine Learning and Artificial Intelligence algorithms. Concluding with the new services that can be offered following the digital transformation 4.0 process of the operating block. Using the tools made available by the most advanced Engineering, an operating block was redesigned, safer for patients and medical staff and more efficient from a conduction point of view. This is done using an administration model that was first conceptualized, designed and then implemented adopting what is made available by Industry 4.0, as well as a series of Management Engineering methodologies aimed at an optimized government of complex systems. Through the data collected by appropriate sensors and translated by the software into usable information, there is an optimal use of the available resources, furthermore, the activities for which improvements can be made with the benefit of patients and structures are identified

NMR Evidence for Charge Inhomogeneity in Stripe Ordered La_{1.8-x}Eu_{0.2}Sr_{x}CuO_4

We report ^{17}O Nuclear Magnetic Resonance (NMR) results in the stripe ordered La_{1.8-x}Eu_{0.2}Sr_{x}CuO_4 system. Below a temperature T_q ~ 80K, the local electric field gradient (EFG) and the absolute intensity of the NMR signal of the planar O site exhibit a dramatic decrease. We interpret these results as microscopic evidence for a spatially inhomogeneous charge distribution, where the NMR signal from O sites in the domain walls of the spin density modulation are wiped out due to large hyperfine fields, and the remaining signal arises from the intervening Mott insulating regions.Comment: 4 pages, to appear in Phys. Rev. Let