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Composite quasi-particles with emergent functionalities in spintronic and quantum information science can be realized in correlated materials due to entangled charge, spin, orbital, and lattice degrees of freedom. Here we show that by reducing the lateral dimension of correlated antiferromagnet NiPS 3 flakes to tens of nanometers and thickness to less than ten nanometers, we can switch-off the bulk spin-orbit entangled exciton in the near-infrared (1.47 eV) and activate visible-range (1.8-2.2 eV) transitions. These ultra-sharp lines (<120 μeV at 4.2 K) share the spin-correlated nature of the bulk exciton by displaying a strong linear polarization below Néel temperature. Furthermore, exciton photoluminescence lineshape analysis indicates a polaronic character VIA coupling with at-least 3 phonon modes and a comb-like Stark effect through discretization of charges in each layer. These findings augment the knowledge on the many-body nature of excitonic quasi-particles in correlated antiferromagnets and also establish the nanoscale correlated antiferromagnets as a promising platform for integrated magneto-optic devices.

Background and Aim: Hypoglossal nerve stimulation (HNS) decreases obstructive sleep apnoea (OSA) severity via genioglossus muscle activation and decreased upper airway collapsibility. This study assessed the safety and effectiveness at 6 months post-implantation of a novel device delivering bilateral HNS via a small implanted electrode activated by a unit worn externally, to treat OSA: the Genio™ system., Methods: This prospective, open-label, non-randomised, single-arm treatment study was conducted at eight centres in three countries (Australia, France and the UK). Primary outcomes were incidence of device-related serious adverse events and change in the apnoea-hypopnoea index (AHI). The secondary outcome was the change in the 4% oxygen desaturation index (ODI). Additional outcomes included measures of sleepiness, quality of life, snoring and device use. This trial was registered with ClinicalTrials.gov, number NCT03048604., Results: 22 out of 27 implanted participants (63% male, aged 55.9±12.0 years, body mass index (BMI) 27.4±3.0 kg·m -2 ) completed the protocol. At 6 months BMI was unchanged (p=0.85); AHI decreased from 23.7±12.2 to 12.9±10.1 events·h -1 , a mean change of 10.8 events·h -1 (p<0.001); and ODI decreased from 19.1±11.2 to 9.8±6.9 events·h -1 , a mean change of 9.3 events·h -1 (p<0.001). Daytime sleepiness (Epworth Sleepiness Scale; p=0.01) and sleep-related quality of life (Functional Outcomes of Sleep Questionnaire-10; p=0.02) both improved significantly. The number of bed partners reporting loud, very intense snoring, or leaving the bedroom due to participant snoring decreased from 96% to 35%. 91% of participants reported device use >5 days per week, and 77% reported use for >5 h per night. No device-related serious adverse events occurred during the 6-month post-implantation period., Conclusions: Bilateral HNS using the Genio™ system reduces OSA severity and improves quality of life without device-related complications. The results are comparable with previously published HNS systems despite minimal implanted components and a simple stimulation algorithm., Competing Interests: Conflict of interest: P.R. Eastwood reports support for undertaking trials from Nyxoah SA, during the conduct of the study; support for undertaking trials from Oventus Pty Ltd and Zelda Therapeutics, outside the submitted work. Conflict of interest: M. Barnes has nothing to disclose. Conflict of interest: S.G. MacKay reports grants from NHMRC and Garnett-Passe RWF (conjoint grant), outside the submitted work. Conflict of interest: J.R. Wheatley reports grants from Nyxoah, during the conduct of the study. Conflict of interest: D.R. Hillman reports support for undertaking trials from Nyxoah SA, during the conduct of the study; support for undertaking trials from Oventus Pty Ltd and Zelda Therapeutics, outside the submitted work. Conflict of interest: X-L. Nguyên reports grants from Serenity Medical Services, during the conduct of the study. Conflict of interest: R. Lewis reports personal fees from Nyxoah SA, during the conduct of the study. Conflict of interest: M.C. Campbell reports personal fees from Nyxoah, outside the submitted work. Conflict of interest: B. Pételle reports consultancy fees from Bluesom, support for meeting attendance from Nyxoah, outside the submitted work. Conflict of interest: J.H. Walsh reports support for undertaking trials from Nyxoah SA, during the conduct of the study; support for undertaking trials from Oventus Pty Ltd and Zelda Therapeutics, outside the submitted work. Conflict of interest: A.C. Jones reports personal fees from Nyxoah, during the conduct of the study. Conflict of interest: C.E. Palme reports personal fees from Nyoxah, during the conduct of the study. Conflict of interest: A. Bizon has nothing to disclose. Conflict of interest: N. Meslier has nothing to disclose. Conflict of interest: C. Bertolus has nothing to disclose. Conflict of interest: K.J. Maddison has undertaken sponsored research projects for Nyxoah Pty Ltd, during the conduct of the study; has undertaken sponsored research projects for Nyxoah Pty Ltd, Oventus Pty Ltd and Zelda Pty Ltd, and reports grants from Sir Charles Gairdner Hospital and Australian and New Zealand College of Anaesthetists, outside the submitted work. Conflict of interest: L. Laccourreye reports non-financial support from Medtronic France and Integra LifeSciences Services, outside the submitted work. Conflict of interest: G. Raux has nothing to disclose. Conflict of interest: K. Denoncin has nothing to disclose. Conflict of interest: V. Attali reports personal fees for consultancy from Nyxoah, during the conduct of the study; personal fees for lectures from Resmed, institutional fees for research from Imthera, outside the submitted work. Conflict of interest: F. Gagnadoux has nothing to disclose. Conflict of interest: S.H. Launois is an employee of Serenity Medical Services/Bioserenity, reports personal fees for lectures from Cidelec, travel and/or meeting expenses from Vitalaire, S2A Santé Asten La Poste and UCB Pharma, grants from Resmed, outside the submitted work., (Copyright ©ERS 2020.)

An operationally simple mechanochemical method for the Pd catalysed Buchwald-Hartwig amination of arylhalides with secondary amines has been developed using a Pd PEPPSI catalyst system. The system is demonstrated on 30 substrates and applied in the context of a target synthesis. Furthermore, the performance of the reaction under aerobic conditions has been probed under traditional solution and mechanochemical conditions, the observations are discussed herein.

The insulator-metal transition (IMT) of vanadium dioxide (VO2) has remained a long-standing challenge in correlated electron physics since its discovery five decades ago. Most interpretations of experimental observations have implicitly assumed a homogeneous material response. Here we reveal inhomogeneous behaviour of even individual VO2 microcrystals using pump-probe microscopy and nanoimaging. The timescales of the ultrafast IMT vary from 40±8 fs, that is, shorter than a suggested phonon bottleneck, to 200±20 fs, uncorrelated with crystal size, transition temperature and initial insulating structural phase, with average value similar to results from polycrystalline thin-film studies. In combination with the observed sensitive variations in the thermal nanodomain IMT behaviour, this suggests that the IMT is highly susceptible to local changes in, for example, doping, defects and strain. Our results suggest an electronic mechanism dominating the photoinduced IMT, but also highlight the difficulty to deduce microscopic mechanisms when the true intrinsic material response is yet unclear.

Despite the relatively simple stoichiometry and structure of VO(2), many questions regarding the nature of its famous metal-insulator transition (MIT) remain unresolved. This is in part due to the prevailing use of polycrystalline film samples and the limited spatial resolution in most studies, hindering access to and control of the complex phase behavior and its inevitable spatial inhomogeneities. Here, we investigate the MIT and associated nanodomain formation in individual VO(2) microcrystals subject to substrate stress. We employ symmetry-selective polarization Raman spectroscopy to identify crystals that are strain-stabilized in either the monoclinic M1 or M2 insulating phase at room-temperature. Raman measurements are further used to characterize the phase dependence on temperature, identifying the appearance of the M2 phase during the MIT. The associated formation and spatial evolution of rutile (R) metallic domains is studied with nanometer-scale spatial resolution using infrared scattering-scanning near-field optical microscopy (s-SNOM). We deduce that even for small crystals of VO(2), the MIT is influenced by the competition between the R, M1, and M2 crystal phases with their different lattice constants subjected to the external substrate-induced stress. The results have important implications for the interpretation of the investigations of conventional polycrystalline thin films where the mutual interaction of constituent crystallites may affect the nature of the MIT in VO(2).