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All‐Van der Waals (vdW)‐material‐based heterostructures with atomically sharp interfaces offer a versatile platform for high‐performing spintronic functionalities at room temperature. One of the key components is vdW topological insulators (TIs), which can produce a strong spin‐orbit‐torque (SOT) through the spin‐momentum locking of their topological surface state (TSS). However, the relatively low conductance of the TSS introduces a current leakage problem through the bulk states of the TI or the adjacent ferromagnetic metal layers, reducing the interfacial charge‐to‐spin conversion efficiency (qICS). Here, a vdW heterostructure is used consisting of atomically‐thin layers of a bulk‐insulating TI Sn‐doped Bi1.1Sb0.9Te2S1 and a room‐temperature ferromagnet Fe3GaTe2, to enhance the relative current ratio on the TSS up to ≈20%. The resulting qICS reaches ≈1.65 nm−1 and the critical current density Jc ≈0.9 × 106 Acm−2 at 300 K, surpassing the performance of TI‐based and heavy‐metal‐based SOT devices. These findings demonstrate that an all‐vdW heterostructure with thickness optimization offers a promising platform for efficient current‐controlled magnetization switching at room temperature. [ABSTRACT FROM AUTHOR]

Background/aims: Early diagnosis of esophageal cancer (EC) remains challenging despite the increasing frequency of endoscopic screenings globally. The rapidly increasing number of endoscopic screenings performed over a certain period might influence diagnostic performance. This study evaluated the association between the number of endoscopic screenings and EC detection rates in a nationwide cohort., Methods: This retrospective population-based study used the Korean National Cancer Screening Program database, comprising 32,774,742 males and females aged ≥40 years between 2015 and 2019. Negative binomial regression model and least-squares mean evaluation were used to assess the association between month of the year and EC detection rates., Results: This study enrolled 28,032,590 participants who underwent upper endoscopy. The number of participants in the fourth quarter (October to December: 10,923,142 [39.0%]) was 2.1 times higher than that in the first quarter (January to March: 5,085,087 [18.1%]); this trend continued for all 5 years. Contrarily, detection rates for EC in the fourth quarter (0.08/1,000 person) were half that in the first quarter (0.15/1,000 person). The odds of detecting EC were lowest in November; in 2015 the odds were 0.57 (95% confidence interval, 0.41 to 0.79; p=0.001) times lower and in 2016, they were 0.51 (95% confidence interval, 0.37 to 0.68; p<0.001) times lower compared to January. The predicted detection rates showed a decreasing trend toward the end of the year (p>0.05 for all)., Conclusions: The workload of endoscopists increased excessively with the rising number of endoscopies toward the end of the year, which was reflected by the decreased EC detection rates during this period.

We demonstrate that the mode number of Andreev bound states in bilayer graphene Josephson junctions can be modulated by controlling the superconducting coherence length in situ. By exploiting the quadratic band dispersion of bilayer graphene, we control the Fermi velocity and thus the coherence length via the application of electrostatic gating. Tunneling spectroscopy of the Andreev bound states reveals a crossover from short to long Josephson junction regimes as we approach the charge neutral point of the bilayer graphene. Furthermore, analysis of different mode numbers of the Andreev energy spectrum allows us to estimate the phase-dependent Josephson current quantitatively. Our Letter provides a new way for studying multimode Andreev levels by tuning the Fermi velocity.