Search results for " Spin"

Quantum Phases and Spin Liquid Properties of 1T-TaS2

2021

Quantum materials exhibiting magnetic frustration are connected to diverse phenomena including high-Tc superconductivity, topological order and quantum spin liquids (QSLs). A QSL is a quantum phase (QP) related to a quantum-entangled fluid-like state of matter. Previous experiments on QSL candidate materials are usually interpreted in terms of a single QP, although theories indicate that many distinct QPs are closely competing in typical frustrated spin models. Here we report on combined temperature-dependent muon spin relaxation and specific heat measurements for the triangular-lattice QSL candidate material 1T-TaS2 that provide evidence for competing QPs. The measured properties are assig…

Fractional quantum Hall effect in the interacting Hofstadter model via tensor networks

2017

We show via tensor network methods that the Harper-Hofstadter Hamiltonian for hard-core bosons on a square geometry supports a topological phase realizing the $\nu=1/2$ fractional quantum Hall effect on the lattice. We address the robustness of the ground state degeneracy and of the energy gap, measure the many-body Chern number, and characterize the system using Green functions, showing that they decay algebraically at the edges of open geometries, indicating the presence of gapless edge modes. Moreover, we estimate the topological entanglement entropy by taking a combination of lattice bipartitions that reproduces the topological structure of the original proposals by Kitaev and Preskill,…

Neck Pain Rehabilitation

2016

Neck pain is par excellence one of the most common disorders of the musculoskeletal system, second only to low back pain. It constitutes 40 % of all backache. The International Association for the Study of Pain (IASP) defines pain of cervical origin coming from an area between the nuchal line and another imagi-nary line that passes through the lower end of the spinous process of the first thoracic vertebra and the sagittal plans tangent to the side edges of the neck. This definition considers therefore posterior pain which in turn can be divided into high pain, up to C3, and lower pain, down from C4. Also, as all diseases, it can be divided into acute and chronic neck pain, merely according…

Liver microsomal membrane fluidity and microsomal desaturase activities in adult spontaneously hypertensive rats.

1997

OBJECTIVE The purpose of the present study was to investigate liver microsomal membrane fluidity simultaneously with membrane fatty acid composition and desaturase activities in spontaneously hypertensive rats (SHR). DESIGN AND METHODS The membrane fluidity was determined, after electron spin resonance (ESR) measurement, in SHR compared with normotensive Wistar-Kyoto (WKY) rats, by calculating the order parameter S from ESR spectra of 5-nitroxide stearate and 10-nitroxide stearate, used as spin-labelled fatty acids. Desaturase activities were measured by incubating SHR and WKY rat liver microsomes with [14C]-radiolabeled fatty acids as substrates for desaturation reactions. The fatty acid c…

FeCr2O4 synthetic spinel: heating experiments and oxidation kinetics

2011

Il dibattito sul federalismo nel secondo dopoguerra

2018

Il Movimento Federalista Europeo viene fondato a Milano nel 1943 da Altiero Spinelli con un gruppo di antifascisti, come movimento di idee e di azione, con l’obiettivo di dare vita ad una federazione di Stati Uniti d’Europa. Per Altiero Spinelli, che del movimento fu l’ideatore principale, lo scopo prioritario della lotta politica era quello di assicurare stabilmente al vecchio continente i valori irrinunciabili della pace, della libertà, della democrazia e della giustizia sociale. Sulla scia di tale orientamento si sviluppò un intenso dibattito che, prima ancora della fondazione del Movimento Federalista Europeo, aveva trovato un riscontro teorico nel “Manifesto di Ventotene”, originariame…

Peptides as Versatile Platforms for Quantum Computing

2018

The pursuit of novel functional building blocks for the emerging field of quantum computing is one of the most appealing topics in the context of quantum technologies. Herein we showcase the urgency of introducing peptides as versatile platforms for quantum computing. In particular, we focus on lanthanide-binding tags, originally developed for the study of protein structure. We use pulsed electronic paramagnetic resonance to demonstrate quantum coherent oscillations in both neodymium and gadolinium peptidic qubits. Calculations based on density functional theory followed by a ligand field analysis indicate the possibility of influencing the nature of the spin qubit states by means of contro…

Laparoscopic endopelvic sacral implantation of a Brindley controller for recovery of bladder function in a paralyzed patient

2008

Background: A number of techniques are being investigated to accomplish bladder control recovery in paralyzed patients using the neurostimulation, but currently, all techniques are based on the dorsal implantation of the electrodes using a laminectomy. Methods: On 27 April 2006 we performed a laparoscopic implantation of a Finetech-Brindley bladder controller on the endopelvic sacral roots in a Th8 completely paralyzed woman who had previously undergone the removal of a Brindley controller due to an arachnoiditis after extrathecal implantation with intradural sacral deafferentation. Results: We required about 3.5 h for the entire surgical procedure; no complications occurred and the patient…

Fluorescence and spin properties of defects in single digit nanodiamonds

2009

International audience; This article reports stable photoluminescence and high-contrast optically detected electron spin resonance (ODESR) from single nitrogen-vacancy (NV) defect centers created within ultrasmall, disperse nanodiamonds of radius less than 4 nm. Unexpectedly, the efficiency for the production of NV fluorescent defects by electron irradiation is found to be independent of the size of the nanocrystals. Fluorescence lifetime imaging shows lifetimes with a mean value of around 17 ns, only slightly longer than the bulk value of the defects. After proper surface cleaning, the dephasing times of the electron spin resonance in the nanocrystals approach values of some microseconds, …

Comportamento di nanocompositi PA6/CNT in flusso elongazionale non isotermo

2012

Si sono preparate fibre a matrice poliammidica caricate con CNT. Sono state utilizzate due diverse tipologie di CNT a differente fattore di forma e grado di purezza, ossidate mediante plasma di ossigeno. Le misure di viscosità elongazionale hanno evidenziato che l’introduzione della carica comporta un incremento della MS a fronte di una diminuzione della BSR per tutti i materiali caricati. La tipologia e la funzionalizzazione dei CNT hanno delle notevoli ricadute sul diverso comportamento reologico. Studi morfologici hanno evidenziato che dopo la funzionalizzazione si registrano livelli di dispersione, allineamento e adesione interfacciale più alti. La natura delle interazioni matrice-caric…