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Abstract We observe both s-series and p-series excitons by using sum frequency generation spectroscopy on monolayer (1L-)MX2 (M = Mo, W, X = S, Se) encapsulated by hexagonal boron nitride (hBN). Moreover, we perform numerical calculations with the Rytova-Keldysh potential and obtain the relative dielectric constant of hBN among other parameters. The obtained relative dielectric constant can be approximated by the high-frequency limit of the infrared dispersion even though the exciton binding energies are almost on the phonon resonances in hBN. This suggests that the theoretically indicated modification of the exciton level structure due to the phonon resonances is negligible. The power-law scaling of exciton binding energies indicates that dielectric screening of 1L-MX2 exciton levels other than 1s can be approximated by that of a 3D hydrogen model with the dielectric constant of hBN.

Abstract The Scibar Cosmic-Ray Telescope (SciCRT) is the most promising detector of the Sierra Negra Cosmic Rays Observatory (SN-CRO). At this location, being a target and a tracker of secondary cosmic rays, the SciCRT offers a high probability of observing solar energetic particles and lower energy galactic cosmic rays (LEGCR); also, it allows the identification of incoming particles by measuring their energy deposition. In this work we present a Geant4-based simulation of the energy deposited by neutrons, $$\gamma $$ γ -rays, protons, electrons and muons in the optimally running SciCRT components. We also calculated the detection efficiency of the SciCRT at its current state. Our simulation results provide new information about the SciCRT detection response that may be used as a basis to estimate and analyze the energy spectra of primary particles.

Abstract In recent years, graphene field-effect-transistors (GFETs) have demonstrated an outstanding potential for terahertz (THz) photodetection due to their fast response and high-sensitivity. Such features are essential to enable emerging THz applications, including 6G wireless communications, quantum information, bioimaging and security. However, the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device, so-called access or parasitic resistances. In this work, we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET detectors. Such dual-gate architectures allow us to fine tune (decrease) the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector, respectively. Our results can be well understood by a series resistance model, as shown by the excellent agreement found between the experimental data and theoretical calculations. These findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors. Graphical Abstract

Abstract Collective spin-wave excitations, magnons, are promising quasi-particles for next-generation spintronics devices, including platforms for information transfer. In a quantum Hall ferromagnets, detection of these charge-neutral excitations relies on the conversion of magnons into electrical signals in the form of excess electrons and holes, but if the excess electron and holes are equal, detecting an electrical signal is challenging. In this work, we overcome this shortcoming by measuring the electrical noise generated by magnons. We use the symmetry-broken quantum Hall ferromagnet of the zeroth Landau level in graphene to launch magnons. Absorption of these magnons creates excess noise above the Zeeman energy and remains finite even when the average electrical signal is zero. Moreover, we formulate a theoretical model in which the noise is produced by equilibration between edge channels and propagating magnons. Our model also allows us to pinpoint the regime of ballistic magnon transport in our device.

Abstract There are numerous wooden historical artifacts in Kyoto and other parts of Japan, including Buddhist statues or Shinto deities. The identification of wood species in these historical artifact is desirable for both repair and maintenance purposes. The most common method of identifying wood species involves examining samples taken from the artifacts. However, intentional sampling from old cultural artifacts is prohibited in Japan. As a result, we attempted to determine the wood species of old statues non-destructively using near-infrared spectroscopy (NIRS). In this article, we developed the softwood and hardwood separation model using NIRS to compare the prediction accuracy for few algorithms. The model was created based on wood samples stored in the xylarium of the Forestry and Forest Products Research Institute (TWTw). We then applied this model to old Buddhist statues in order to classify them as either softwood or hardwood. These Buddhist statues were housed in Nazenji temple and are believed to have been carved during the Heian period (8th–12th century). For the near-infrared (NIR) measurements, we collected diffuse reflectance spectra from TWTw sample and Buddhist statues using same spectrometer. Initially, we used the soft independent modeling of class analogy method (SIMCA), partial least squares discriminant analysis (PLS_DA), and support vector machine to analyze the NIR spectra obtained from the TWTw wood samples. Subsequently, we applied the NIR spectra obtained from several Buddhist statues in Nazenji temple to the aforementioned separation model and determined whether spectra data were classified as the softwood or hardwood. Finally, wood specimens detached naturally from the Buddhist statues over time were observed under microscopic analysis to identify the wood species. As comparing the prediction accuracy of few algorithms, SIMCA had a poor result, but PLS_DA had a good result. PLS_DA had better discrimination because it performed calculations to improve regression from both explanatory variables and objective variables.

Particle dark matter could belong to a multiplet that includes an electrically charged state. WIMP dark matter (χ0) accompanied by a negatively charged excited state (χ−) with a small mass difference (e.g. < 20 MeV) can form a bound-state with a nucleus such as xenon. This bound-state formation is rare and the released energy is O(1−10) MeV depending on the nucleus, making large liquid scintillator detectors suitable for detection. We searched for bound-state formation events with xenon in two experimental phases of the KamLAND-Zen experiment, a xenon-doped liquid scintillator detector. No statistically significant events were observed. For a benchmark parameter set of WIMP mass mχ0=1 TeV and mass difference Δm=17 MeV, we set the most stringent upper limits on the recombination cross section times velocity 〈σv〉 and the decay-width of χ− to 9.2×10−30 cm3/s and 8.7×10−14 GeV, respectively at 90% confidence level.

Measurements of dissolved organic carbon (DOC), nitrogen (DON), and phosphorus (DOP) concentrations are used to characterize the dissolved organic matter (DOM) pool and are important components of biogeochemical cycling in the coastal ocean. Here, we present the first edition of a global database (CoastDOM v1; available at https://doi.org/10.1594/PANGAEA.964012, Lønborg et al., 2023) compiling previously published and unpublished measurements of DOC, DON, and DOP in coastal waters. These data are complemented by hydrographic data such as temperature and salinity and, to the extent possible, other biogeochemical variables (e.g. chlorophyll a, inorganic nutrients) and the inorganic carbon system (e.g. dissolved inorganic carbon and total alkalinity). Overall, CoastDOM v1 includes observations of concentrations from all continents. However, most data were collected in the Northern Hemisphere, with a clear gap in DOM measurements from the Southern Hemisphere. The data included were collected from 1978 to 2022 and consist of 62 338 data points for DOC, 20 356 for DON, and 13 533 for DOP. The number of measurements decreases progressively in the sequence DOC > DON > DOP, reflecting both differences in the maturity of the analytical methods and the greater focus on carbon cycling by the aquatic science community. The global database shows that the average DOC concentration in coastal waters (average ± standard deviation (SD): 182±314 µmol C L−1; median: 103 µmol C L−1) is 13-fold higher than the average coastal DON concentration (13.6±30.4 µmol N L−1; median: 8.0 µmol N L−1), which is itself 39-fold higher than the average coastal DOP concentration (0.34±1.11 µmol P L−1; median: 0.18 µmol P L−1). This dataset will be useful for identifying global spatial and temporal patterns in DOM and will help facilitate the reuse of DOC, DON, and DOP data in studies aimed at better characterizing local biogeochemical processes; closing nutrient budgets; estimating carbon, nitrogen, and phosphorous pools; and establishing a baseline for modelling future changes in coastal waters.

Abstract Raman scattering excitation (RSE) is an experimental technique in which the spectrum is made up by sweeping the excitation energy when the detection energy is fixed. We study the low-temperature (T = 5 K) RSE spectra measured on four high quality monolayers (ML) of semiconducting transition metal dichalcogenides (S-TMDs), i.e. MoS2, MoSe2, WS2, and WSe2, encapsulated in hexagonal BN. The outgoing resonant conditions of Raman scattering reveal an extraordinary intensity enhancement of the phonon modes, which results in extremely rich RSE spectra. The obtained spectra are composed not only of Raman-active peaks, i.e. in-plane E $${}^{{\prime} }$$ ′ and out-of-plane A $${}_{1}^{{\prime} }$$ 1 ′ , but the appearance of 1st, 2nd, and higher-order phonon modes is recognized. The intensity profiles of the A $${}_{1}^{{\prime} }$$ 1 ′ modes in the investigated MLs resemble the emissions due to neutral excitons measured in the corresponding PL spectra for the outgoing type of resonant Raman scattering conditions. Furthermore, for the WSe2 ML, the A $${}_{1}^{{\prime} }$$ 1 ′ mode was observed when the incoming light was in resonance with the neutral exciton line. The strength of the exciton-phonon coupling (EPC) in S-TMD MLs strongly depends on the type of their ground excitonic state, i.e. bright or dark, resulting in different shapes of the RSE spectra. Our results demonstrate that RSE spectroscopy is a powerful technique for studying EPC in S-TMD MLs.

Abstract Recently, magic-angle twisted bilayer graphene (MATBLG) has emerged with various interaction-driven novel quantum phases at the commensurate fillings of the moiré superlattice, while the charge neutrality point (CNP) remains mostly a trivial insulator. Here, we show an emerging phase of compensated semimetallicity at the CNP of twisted double bilayer graphene (TDBLG), a close cousin of MATBLG, with signatures of electronic correlation. Using electrical and thermal transport, we find two orders of magnitude enhancement of the thermopower at magnetic fields much smaller than the extreme quantum limit, accompanied by large magnetoresistance ( ~ 2500%) at CNP, providing strong experimental evidence of compensated semimetallicity at CNP of TDBLG. Moreover, at low temperatures, we observe unusual sublinear temperature dependence of resistance. A recent theory1 predicts the formation of an excitonic metal near CNP, where small electron and hole pockets co-exist. We understand this sublinear temperature dependence in terms of critical fluctuations in this theory.

Abstract The coherent dynamics of a quantum mechanical two-level system passing through an anti-crossing of two energy levels can give rise to Landau-Zener-Stückelberg-Majorana (LZSM) interference. LZSM interference spectroscopy has proven to be a fruitful tool to investigate charge noise and charge decoherence in semiconductor quantum dots (QDs). Recently, bilayer graphene has developed as a promising platform to host highly tunable QDs potentially useful for hosting spin and valley qubits. So far, in this system no coherent oscillations have been observed and little is known about charge noise in this material. Here, we report coherent charge oscillations and $${T}_{2}^{*}$$ T 2 * charge decoherence times in a bilayer graphene double QD. The charge decoherence times are measured independently using LZSM interference and photon assisted tunneling. Both techniques yield $${T}_{2}^{*}$$ T 2 * average values in the range of 400–500 ps. The observation of charge coherence allows to study the origin and spectral distribution of charge noise in future experiments.

Abstract Optoelectronics is a valuable solution to scale up wireless links frequency to sub-THz in the next generation antenna systems and networks. Here, we propose a low-power consumption, small footprint building block for 6 G and 5 G new radio wireless transmission allowing broadband capacity (e.g., 10–100 Gb/s per link and beyond). We demonstrate a wireless datalink based on graphene, reaching setup limited sub-THz carrier frequency and multi-Gbit/s data rate. Our device consists of a graphene-based integrated optoelectronic mixer capable of mixing an optically generated reference oscillator approaching 100 GHz, with a baseband electrical signal. We report >96 GHz optoelectronic bandwidth and −44 dB upconversion efficiency with a footprint significantly smaller than those of state-of-the-art photonic transmitters (i.e.,

Abstract Recent experiments in magic-angle twisted bilayer graphene have revealed a wealth of novel electronic phases as a result of interaction-driven spin-valley flavour polarisation. In this work, we investigate correlated phases due to the combined effect of spin-orbit coupling-enhanced valley polarisation and the large density of states below half filling of the moiré band in twisted bilayer graphene coupled to tungsten diselenide. We observe an anomalous Hall effect, accompanied by a series of Lifshitz transitions that are highly tunable with carrier density and magnetic field. The magnetisation shows an abrupt change of sign near half-filling, confirming its orbital nature. While the Hall resistance is not quantised at zero magnetic fields—indicating a ground state with partial valley polarisation—perfect quantisation and complete valley polarisation are observed at finite fields. Our results illustrate that singularities in the flat bands in the presence of spin-orbit coupling can stabilise ordered phases even at non-integer moiré band fillings.

Abstract The coexistence of gate-tunable superconducting, magnetic and topological orders in magic-angle twisted bilayer graphene provides opportunities for the creation of hybrid Josephson junctions. Here we report the fabrication of gate-defined symmetry-broken Josephson junctions in magic-angle twisted bilayer graphene, where the weak link is gate-tuned close to the correlated insulator state with a moiré filling factor of υ = −2. We observe a phase-shifted and asymmetric Fraunhofer pattern with a pronounced magnetic hysteresis. Our theoretical calculations of the junction weak link—with valley polarization and orbital magnetization—explain most of these unconventional features. The effects persist up to the critical temperature of 3.5 K, with magnetic hysteresis observed below 800 mK. We show how the combination of magnetization and its current-induced magnetization switching allows us to realise a programmable zero-field superconducting diode. Our results represent a major advance towards the creation of future superconducting quantum electronic devices.

Abstract Single spin-defects in 2D transition-metal dichalcogenides are natural spin-photon interfaces for quantum applications. Here we report high-field magneto-photoluminescence spectroscopy from three emission lines (Q1, Q2, and Q*) of He-ion induced sulfur vacancies in monolayer MoS2. Analysis of the asymmetric PL lineshapes in combination with the diamagnetic shift of Q1 and Q2 yields a consistent picture of localized emitters with a wave function extent of ~3.5 nm. The distinct valley-Zeeman splitting in out-of-plane B-fields and the brightening of dark states through in-plane B-fields necessitates spin-valley selectivity of the defect states and lifted spin-degeneracy at zero field. Comparing our results to ab initio calculations identifies the nature of Q1 and Q2 and suggests that Q* is the emission from a chemically functionalized defect. Analysis of the optical degree of circular polarization reveals that the Fermi level is a parameter that enables the tunability of the emitter. These results show that defects in 2D semiconductors may be utilized for quantum technologies.

Abstract Optoelectronic sampling is the ultimate method to perform ultra‐high frequency analog‐to‐digital conversion. Thanks to the ps photo‐thermo‐bolometric effect in high mobility hexagonal boron nitride (h‐BN) encapsulated graphene, a state‐of‐the‐art optoelectronic sampler over a 40 GHz bandwidth using a 4 ps pulsed laser is demonstrated. The superior transport and optoelectronic linearities of this graphene sampler lead to very high harmonic rejections below –43 dB above 20 GHz. With a physics‐based microscopic model, it is shown that harmonics are generated by optoelectronics saturation effects and only appear when carrier energy reaches that of optical phonons, which is very high in h‐BN encapsulated graphene. This device is the first ultra‐fast optoelectronic sampler based on the bolometric effect.

Liquid food can likely cause accidental ingestion in patients with dysphagia. This study proposes a handheld stirrer-type rotational viscometer that can be used in the kitchen or at meals for dysphagia. A novel rotational viscometer is proposed considering that the rotation speed of the handheld stirrer is inversely proportional to the viscosity of the fluids to be stirred. We adopt the sensorless control strategy. We use a small brush-type DC motor, which functions as a rotary actuator and a rotational speed sensor to realize the proposed device. Because the proposed viscometer is used in the aforementioned fields, it must be compact, handy, simple in structure, and low-cost. We apply the proposed viscometer to fluids with viscosities ranging from 5000 to 54000 mPa $\cdot \text{s}$ for testing, using a cylindrical rotor with a length of 15 mm and diameter of 10 mm. The repeatability and linearity as a measurement instrument evaluated by the ASTM standards E3116-18 are less than 5% and 4% for the aforementioned fluids under the temperature of 11 °C, respectively. Because the thickness of liquid food is classified into only three categories (mildly, moderately, and extremely thick), the accuracy of this method is sufficient for the measurement.

Quantum Hall edge channels provide a platform to study electron interference, however understanding decoherence in these systems remains an open problem. Jo et al. realize a regime of suppressed decoherence in an electronic Mach-Zehnder interferometer formed in a graphene quantum Hall pn junction.

The knowledge of quantum numbers of the edge modes is essential for understanding fractional Hall states containing counter-propagating downstream and upstream modes. Here the authors identify the edge quantum numbers by probing a crossover from non-equilibrated to equilibrated edge mode regime in thermal conductance.

We demonstrate gate-tunable giant field-dependent nonreciprocal transport (magnetochiral anisotropy) in a noncentrosymmetric superconductor T_{d}-MoTe_{2} in the thin limit. Giant magnetochiral anisotropy (MCA) with a rectification coefficient (or a figure of merit) γ=3.1×10^{6}T^{−1}A^{−1} is observed at 230 mK, below the superconducting transition temperature (T_{c}). This is one of the largest values reported so far and may be attributed to the reduced symmetry of the crystal structure. The temperature dependence of γ indicates that ratchetlike motion of magnetic vortices is the origin of the MCA, as supported by our theoretical model. For bilayer (2 L) T_{d}-MoTe_{2}, we can successfully modulate γ by gating. Our experimental results provide a new route to realizing electrically controllable superconducting rectification devices in a single material.

An asymmetric dual-grating gate bilayer graphene-based field effect transistor (ADGG-GFET) with an integrated bowtie antenna was fabricated and its response as a Terahertz (THz) detector was experimentally investigated. The device was cooled down to 4.5 K, and excited at different frequencies (0.15, 0.3 and 0.6 THz) using a THz solid-state source. The integration of the bowtie antenna allowed to obtain a substantial increase in the photocurrent response (up to 8 nA) of the device at the three studied frequencies as compared to similar transistors lacking the integrated antenna (1 nA). The photocurrent increase was observed for all the studied values of the bias voltage applied to both the top and back gates. Besides the action of the antenna that helps the coupling of THz radiation to the transistor channel, the observed enhancement by nearly one order of magnitude of the photoresponse is also related to the modulation of the hole and electron concentration profiles inside the transistor channel by the bias voltages imposed to the top and back gates. The creation of local n and p regions leads to the formation of homojuctions (np, pn or pp+) along the channel that strongly affects the overall photoresponse of the detector. Additionally, the bias of both back and top gates could induce an opening of the gap of the bilayer graphene channel that would also contribute to the photocurrent.

Preceding a core-collapse supernova (CCSN), various processes produce an increasing amount of neutrinos of all flavors characterized by mounting energies from the interior of massive stars. Among them, the electron antineutrinos are potentially detectable by terrestrial neutrino experiments such as KamLAND and Super-Kamiokande (SK) via inverse beta decay interactions. Once these pre-supernova (pre-SN) neutrinos are observed, an early warning of the upcoming CCSN can be provided. In light of this, KamLAND and SK, both located in the Kamioka mine in Japan, have been monitoring pre-SN neutrinos since 2015 and 2021, respectively. Recently, we performed a joint study between KamLAND and SK on pre-SN neutrino detection. A pre-SN alert system combining the KamLAND detector and the SK detector was developed and put into operation, which can provide a supernova alert to the astrophysics community. Fully leveraging the complementary properties of these two detectors, the combined alert is expected to resolve a pre-SN neutrino signal from a 15 M _⊙ star within 510 pc of the Earth at a significance level corresponding to a false alarm rate of no more than 1 per century. For a Betelgeuse-like model with optimistic parameters, it can provide early warnings up to 12 hr in advance.

Superconducting (SC) tokamak JT-60SA plays an essential role in fusion research and development by supporting and complementing the ITER project, providing directions to the DEMO design activity and fostering next generation scientists and engineers. Since the short circuit incident at the terminal joints of equilibrium field coil #1 during the integrated commissioning (IC) in March 2021, both EU and JA implementing agencies (IAs) have examined how to ensure safe operation of JT-60SA by mitigating the risk of possible discharge occurrence inside the cryostat. Based on the experience of the global Paschen tests, the IAs have established a strategy of risk mitigation measures, which is a combination of (i) reinforcement of insulation, (ii) avoiding unnecessary voltage application to the coil systems and (iii) immediate de-energization of the coils when deteriorated vacuum conditions are detected. Thanks to the considerable efforts of the Integrated Project Team members, the IC restarted in May 2023. After confirmation of the SC state of the coil systems (TF, EF and CS), the coil energization test and the plasma operation phase 1 (OP-1) started. The first plasma was successfully achieved on 23 October 2023 with a limited value of voltage and current applied to the coils. The plasma configuration control was also confirmed with low plasma current and low auxiliary heating power conditions. Based on the IO–F4E–QST collaboration, activities of JT-60SA have been shared with the IO and provided an important lesson for ITER assembly and commissioning, and will provide an outstanding contribution to fusion research at large. After OP-1, maintenance & enhancement phase 1 (M/E-1) starts from January 2024, in which in-vessel components are installed, and heating and diagnostic systems are extensively upgraded to allow a high power heating experiment planned in OP-2. In order to make the best use of JT-60SA, a newly organized JT-60SA experiment team will refine the research plan for the future high heating power operation phase.

Graphene has long been considered to be a promising host for spin qubits, however a demonstration of long spin relaxation times for a potential qubit has been lacking. Here, the authors report the electrical measurement of the single-electron spin relaxation time exceeding 200 μs in a bilayer graphene quantum dot.

Introduction Prevention of perinatal depression beginning from the antenatal period is essential. Objectives This study aimed to investigate the effectiveness of recently developed internet-delivered cognitive behavioral therapy (iCBT) for preventing the onset of a major depressive episode (MDE) in the third trimester and at 3 months postpartum. Methods This is a two-arm, parallel-group, general-information controlled, randomized controlled trial. Participants were 5,017 pregnant women at 16–20 weeks’ gestation without MDE at baseline. They were randomly assigned to an iCBT (intervention; n = 2,509) or general-information (control; n = 2,508) group, stratified by psychological distress at baseline. The primary outcomes were the numbers of new MDE onsets, measured using the World Health Organization Composite International Diagnostic Interview 3.0, at 32 weeks’ gestation and at 3 months postpartum. Results New MDE onset was reported by 59 participants (2.35%) in the intervention group and 73 (2.91%) in the control group during follow-up. Compared with the control group, the hazard ratio (HR) of MDE in the intervention group was 0.85 (95% CI 0.61–1.20). Among participants who scored between 5 and 8 on K6 at baseline, 10 (1.37%) in the intervention group reported new onset of MDE, compared with 28 (3.81%) in the control group, and the HR of MDE was 0.38 (95%CI 0.19–0.79). Conclusions No intervention effect was found for iCBT in preventing new onset of perinatal MDE. iCBT might prevent perinatal depression only among pregnant women with subthreshold depressive symptoms. Disclosure of Interest None Declared

In order to predict slope failure, it is useful to be able to grasp the state of root system development of trees by remote sensing techniques. Since there is a positive correlation between tree diameter and root system development, a field survey to verify how predictable the number of trees and breast height diameter can be from LiDAR data was conducted in the Abukuma Mountains Granite Area and the Yamizo Mountains Jurassic Sedimentary Rock Area. It was carried out for the logging site. As a result, it was found that the relative tree density can be determined and that the laser transmittance and the sum of cross-sectional areas of the trees are inversely correlated.

Abstract We have investigated the laser-induced valley polarization and coherence of encapsulated MoS2 monolayer as a function of temperature, power density, and spatial position. Besides a non-monotonic dependence on temperature, recently attributed to a dependence of the valley relaxation time on the momentum scattering rate, we observe a two-fold increase of the valley polarization when increasing the laser excitation power. We attribute this effect to a local heating induced by the energy relaxation of photoexcited excitons and to an increase of the exciton-exciton scattering rate. In contrast, only a moderate enhancement of valley coherence is observed, which exhibits a dramatic drop after further increasing the excitation power. We attribute this behaviour to the detrimental role of exciton-exciton interactions on the pure dephasing rate responsible for the loss of coherence between the valleys. This manifests itself by a strong dip in the spatial profile of the valley coherence at high photoexcited densities.

Recently graphene has emerged as a new platform for the study of quantum Hall states. Here, by means of noise measurements, the authors report evidence for the existence of the upstream mode and its ballistic nature in the hole-conjugate fractional quantum Hall state in a bilayer graphene device.

Understanding the interaction between spin and valley degrees of freedom in graphene-based quantum dots underpins their applications in electronics and quantum information. Here, the authors study the low-energy spectrum and resolve the spin-valley coupling in single-electron quantum dots in bilayer graphene.

Here, the authors investigate the lattice dynamics of twisted hexagonal boron nitride layers via nano-infrared spectroscopy, showing local and stacking-dependent variations of the optical phonon frequencies associated to the interaction with the graphite substrate.

Abstract Two-dimensional layered materials offer the possibility to create artificial vertically stacked structures possessing an additional degree of freedom—the interlayer twist. We present a comprehensive optical study of artificially stacked bilayers (BLs) MoS $$_2$$ 2 encapsulated in hexagonal BN with interlayer twist angle ranging from 0 $$^{\circ }$$ ∘ to 60 $$^{\circ }$$ ∘ using Raman scattering and photoluminescence spectroscopies. It is found that the strength of the interlayer coupling in the studied BLs can be estimated using the energy dependence of indirect emission versus the A $$_\text {1g}$$ 1g –E $$_\text {2g}^1$$ 2g 1 energy separation. Due to the hybridization of electronic states in the valence band, the emission line related to the interlayer exciton is apparent in both the natural (2H) and artificial (62 $$^\circ $$ ∘ ) MoS $$_2$$ 2 BLs, while it is absent in the structures with other twist angles. The interlayer coupling energy is estimated to be of about 50 meV. The effect of temperature on energies and intensities of the direct and indirect emission lines in MoS $$_2$$ 2 BLs is also quantified.

Excitons in atomically thin crystals couple strongly with light. Here, the authors observe lattice polaritons in a tunable open optical cavity at room temperature, with an imprinted photonic lattice strongly coupled to excitons in a WS2 monolayer.

It was suggested that the breakdown of the quantum Hall effect in graphene originates from the coupling between counter propagating edge modes. Here, by using scanning gate microscopy, the authors propose a microscopic mechanism of this coupling due to antidots present at graphene edges.

Optical receivers based on graphene still suffer from low responsivity. Here, the authors integrate a photo-thermoelectric graphene photodetector with a Si micro-ring resonator, and obtain a voltage responsivity ~ 90 V/W and a reduction of energy-per-bit consumption, enabling performance on par with mature semiconductor technology.

Introduction Goal attainment scaling (GAS) is a method to assess the patient experience of whether a treatment is successful and capture outcomes across a diverse range of goal areas. However, this approach has not yet been used in assessing the treatment of Major Depressive Disorder (MDD) in Japan. GAS was first developed by Kiresuk and Sherman in the 1968, it is increasingly recognised as a sensitive method for recording patient-centred outcomes throughout the course of treatment. Objectives To demonstrate the effectiveness of vortioxetine on patient’s goal achievement and depressive symptoms, emotional, cognitive, overall function and quality of life. Methods VGOAL-J is a prospective, multi-center, observational cohort study of outpatients initiating vortioxetine treatment for MDD in Japan. Patients with a diagnosis of MDD according to DSM-5 who are 18 to 65 years will be enrolled from 20 sites in Japan and followed for 24 weeks. A total number of 120 patients is planned for enrolment. Primary outcome measures are GAS-D, WPAI, secondary outcome measures include Montgomery – Åsberg Depression Rating Scale (MADRS), Sheehan Disability Scale (SDS), Perceived Deficits Questionnaire-Depression 5-item (PDQ-D-5), Oxford Depression Questionnaire (ODQ), EuroQol-5 Dimension (EQ-5D). Safety will be also assessed with Adverse Events collected during the study. Results The results will be disseminated in late 2022 and provide new insights on GAS-D as an effective strategy to assess MDD treatment in Japan. Conclusions We expect to observe patients treated with vortioxetine achieving their treatment goals as assessed by GAS-D and improvements on patient- and clinician-reported measures in real-world settings. Disclosure Prof. K. Watanabe reports consultancies undertaken for Eli Lilly, Otsuka Pharmaceutical, Sumitomo Dainippon Pharma, Taisho Toyama Pharmaceutical, and Takeda Pharmaceutical, honoraria received from Daiichi Sankyo, Eisai, Eli Lilly, GlaxoSmithKline, J

Here, a strong nonlinearity of the gate-induced tunnel junction in bilayer graphene is used for efficient terahertz detection. The improved signal-to-noise ratio, as compared to conventional detectors, offers the application of steep-switching transistors in terahertz technology.

Here, the authors show that Brown-Zak fermions in graphene-on-boron-nitride superlattices exhibit mobilities above 106 cm2/V s and micrometer scale ballistic transport.

One advantage of van der Waals materials is the ability to combine different materials in layers to form new heterostructures. Here, the authors investigate heterostructures of CrBr3 and MoSe2, and find that the ferromagnetism of CrBr3 enhances the valley dependent optical response of the MoSe2.

Excitons control the optical properties of transition metal dichalcogenide monolayers. Here, the authors measure the exciton fine structure of MoS2 and MoSe2 monolayers encapsulated in hBN in magnetic fields up to 30 T, and observe a brightening of the spin-forbidden dark excitons in MoS2.

Purpose: This animal experiment investigated how sesame seed (Sesamum indicum; SSI) extract affects bone metabolism in ovariectomized (Ovx) rats. Materials and methods: Female Wistar rats (12 weeks old) were randomly assigned to the Baseline control (BC), Sham, Ovx, and Ovx + SSI groups (n = 6-10). Animals in the BC group were sacrificed immediately. Rats in the other groups underwent sham surgery (Sham) or bilateral ovariectomy (Ovx and Ovx + SSI). Rats in the Ovx + SSI group were given custom diets, and BMD and bone histomorphometry were evaluated 13 weeks post-surgery. Results: The femur BMD in the Ovx + SSI group was lower than in the Ovx group, as were the measurements for bone formation rate and mineralizing surface. Conclusion: Administration of a methanol extract of sesame seeds decreased femur BMD in Ovx rats.

Experimental control of electron-electron interactions in materials is challenging. Here, the authors control the interactions by proximity screening with gate dielectrics of nanometer thickness, revealing qualitative changes in concentration and temperature dependences, and validating their analysis using electron hydrodynamics and umklapp scattering approaches.

Macroalgal beds have drawn attention as one of the vegetated coastal ecosystems that act as atmospheric CO2 sinks. Although macroalgal metabolism as well as inorganic and organic carbon flows are important pathways for CO2 uptake by macroalgal beds, the relationships between macroalgal metabolism and associated carbon flows are still poorly understood. In the present study, we investigated carbon flows, including air–water CO2 exchange and budgets of dissolved inorganic carbon, total alkalinity, and dissolved organic carbon (DOC), in a temperate macroalgal bed during the productive months of the year. To assess the key mechanisms responsible for atmospheric CO2 uptake by the macroalgal bed, we estimated macroalgal metabolism and lateral carbon flows (i.e., carbon exchanges between the macroalgal bed and the offshore area) by using field measurements of carbon species, a field-bag method, a degradation experiment, and mass-balance modeling in a temperate Sargassum bed over a diurnal cycle. Our results showed that macroalgal metabolism and lateral carbon flows driven by water exchange affected air–water CO2 exchange in the macroalgal bed and the surrounding waters. Macroalgal metabolism caused overlying waters to contain low concentrations of CO2 and high concentrations of DOC that were efficiently exported offshore from the macroalgal bed. These results indicate that the exported water can potentially lower CO2 concentrations in the offshore surface water and enhance atmospheric CO2 uptake. Furthermore, the Sargassum bed exported 6 %–35 % of the macroalgal net community production (NCP; 302–1378 mmol C m−2 d−1) as DOC to the offshore area. The results of degradation experiments showed that 56 %–78 % of macroalgal DOC was refractory DOC (RDOC) that persisted for 150 d; thus, the Sargassum bed exported 5 %–20 % of the macroalgal NCP as RDOC. Our findings suggest that macroalgal beds in habitats associated with high water exchange rates can create significant CO2 sinks around them and export a substantial amount of DOC to offshore areas.

Long carrier lifetimes are beneficial for graphene-based optoelectronics, but carrier recombination processes in graphene possess sub-picosecond characteristic times. Here, the authors report carrier lifetimes ~30 ps at low energy in graphene/hBN Zener-Klein transistors, attributed to interband Auger processes.

Purpose: Osteoporosis is a major health concern in postmenopausal women. The aim of the study was to investigate the effect of Hericium erinaceus (H. erinaceus), also known as the Lion’s Mane mushroom, consumption on bone metabolism in ovariectomized (Ovx) rats. Materials and Methods: Rats in the Baseline group were sacrificed immediately, whereas rats in the Sham group underwent sham surgery, and those in the Ovx and Ovx + HE groups underwent bilateral Ovx. A diet containing the methanol extract of H. erinaceus was given to the Ovx+HE group for 13 weeks. Results: There was no significant difference in the femoral bone mass between the Ovx and Ovx+HE groups. In the histomorphometric study of the proximal tibial metaphysis, the osteoblast surface, mineralizing surface, and fat cell number were lower in the Ovx+HE group than those in the Ovx group. Conclusion: The present findings suggest that H. erinaceus does not prevent but rather accelerates bone loss in Ovx rats.

The triple alpha reaction is one of the most important reactions in the nuclear astrophysics. However, its reaction rate in high temperature environments at T9> 2 was still uncertain. One of the major origins of the uncertainty was that the radiative-decay probability of the 31− state in 12C was unknown. In the present work, we have determined the radiative-decay probability of the 31− state to be 1.3−1.1+1.2×10−6 by measuring the 1H(12C,12Cp) reaction for the first time, and derived the triple alpha reaction rate in high temperature environments from the measured radiative-decay probability. The present result suggests that the 31− state noticeably enhances the triple alpha reaction rate although the contribution from the 31− state had been assumed to be small.

The rational design of optoelectronic devices based on 2D materials relies on quantitative knowledge of their excitonic properties. Here the authors perform circularly-polarized absorption spectroscopy on monolayer $${{\rm{MoS}}}_{2},{{\rm{MoSe}}}_{2},{{\rm{MoTe}}}_{2}$$ MoS2,MoSe2,MoTe2 and $${{\rm{WS}}}_{2}$$ WS2 in magnetic fields up to 91 T, and derive the effective exciton masses, binding energies, radii, dielectric properties, and free-particle bandgaps of these monolayer semiconductors

Dirac fermion optics leverages p-n junctions and Klein tunnelling barriers present in materials to implement complex optical functions and devices, including reflectors, collimators, and Dirac fermion microscopes. Here, the authors fabricate Dirac fermion corner reflectors using bottom-gate-defined barriers in hBN-encapsulated graphene, and demonstrate high-frequency operation.

Light emitters can be induced in transition metal dichalcogenides by defect engineering, but challenges remain in their controlled spatial positioning. Here, the authors irradiate monolayer MoS2 with a sub-nm focused helium ion beam to deterministically create defects, and obtain spectrally narrow emission lines that produce photons in the visible spectral range

The authors present electroluminescence measurements of light-emitting devices based on van der Waals heterostructures, and observe a lower than expected threshold voltage for intralayer electroluminescence, attributed to non-radiative Auger-type recombination of interlayer excitons and resulting energy transfer.

The unique valley and spin texture of atomically thin transition metal dichalcogenides (TMDs) allows the observation of the valley Zeeman effect for neutral and charged excitons. Here, the authors unveil the underlying physics of the magneto-optical response and valley Zeeman splitting of trions in tungsten-based TMDs.

Calcium carbonates (CaCO3) often accumulate in mangrove and seagrass sediments. Here the authors conducted a meta-analysis of inorganic carbon burial rates in mangrove and seagrass sediments and found that CaCO3 burial contributes to Blue Carbon ecosystems’ capacity to offset sea-level rise without undermining the role as CO2 sinks.