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Engineering Conjugated Bridges in TPE-BT-Based Donor–Acceptor Molecules for Optimized Resistive Random Access Memory
No full textFour donor–acceptor (D-A) type organic small molecules, namely, 4,7-bis(4-(1,2,2-triphenylvinyl)phenyl)benzo[c][1,2,5]thiadiazole(TPE-BT), 4,7-bis((4-(1,2,2-triphenylvinyl)phenyl)ethynyl)benzo[c][1,2,5]thiadiazole(TPE-ynl-BT), 4,7-bis(5-(4-(1,2,2-triphenylvinyl)phenyl)thiophen-2-yl)benzo[c][1,2,5]thiadiazole (TPE-Th-BT), and 4,7-bis((5-(4-(1,2,2-triphenylvinyl)phenyl)thiophen-2yl)ethynyl)benzo[c][1,2,5]thiadiazole(TPE-Th-ynl-BT), each incorporating unique conjugated bridges, are designed, synthesized, and integrated into resistive random access memory (RRAM) devices. Current–voltage (I–V) measurements indicate that the TPE-BT, TPE-ynl-BT and TPE-Th-BT based devices exhibit write-once-read-many-times (WORM) characteristics, while TPE-Th-ynl-BT based devices show a stable flash-type switching behavior. In comparison to TPE-BT, the memory devices constructed with TPE-ynl-BT, TPE-Th-BT and TPE-Th-ynl-BT, which include additional conjugated bridges, exhibit nonvolatile memory capabilities with reduced threshold voltages, higher ION/IOFF (104:1), enhanced stability, and improved reproducibility. The photophysical, electrochemical analyses, and X-ray diffraction (XRD) results reveal that incorporating conjugated bridges within molecular structures can enhance data storage performance while reducing power consumption. Our findings demonstrate that these conjugated bridges play a crucial role in optimizing electrical memory characteristics and resistive switching behavior. Moreover, the device fabricated with TPE-Th-ynl-BT is effectively applied to logic gate circuits and American Standard Code for Information Interchange (ASCII) art function, highlighting its promising potential as a smart sensor within artificial intelligence (AI) networks
Impact of interference effects on Higgs-boson searches in the di-top final state at the LHC
No full textThe di-top final state is an important search channel for additional Higgs bosons at the LHC. In this channel, large signal-background interference contributions can strongly distort a resonance peak as it would be expected from a pure signal contribution. Moreover, signal-signal interference effects can have a significant impact if more than one additional scalar particle is present. In this work, we perform a comprehensive model-independent analysis of the various interference contributions considering two additional heavy scalars that can mix with each other. We point out the importance of taking into account loop-level mixing between the scalars. A proper treatment of these mixing effects, which has not been previously carried out for the di-top final state, introduces additional relative phases between different parts of the amplitudes entering the interference contributions which we find to have a strong impact on the di-top invariant mass distribution. We study the interference effects both in an idealistic setting as well as taking into account experimental limitations using Monte-Carlo simulations. We demonstrate that the emerging experimental signatures can be unexpected and difficult to interpret. In particular, we point out that an experimental signature manifesting itself as an excess near the threshold may actually be caused by new scalar particles with much higher masses. We comment in this context on the recent excess that has been observed by the CMS collaboration near the threshold in their searches in the di-top final state
Twin Echo-Enabled Harmonic Generation for Enhanced Coherent Bunching at Short Wavelength
No full textExternally seeded free-electron lasers (FELs) based on harmonic up-conversion schemes represent the most successful approach for obtaining radiation with laser-like properties at short wavelengths. They are however limited in the shortest achievable wavelengths, as the harmonic conversion efficiency decreases with increasing harmonic number, even for echo-enabled harmonic generation (EEHG) [1]. Higher bunching is critical to improve the performance of seeded FELs in the soft X-rays, with large output power and more compact footprint. We analyze the performance at 4 nm and shorter via numerical simulations, demonstrating multi-GW level, fully coherent pulses with laser-like properties, paving the way for externally seeded radiation at 1 nm and beyond
A 100Hz Ti:Sapphire Amplifier Delivering >700mJ Pulses for High Energy Laser Plasma Acceleration
No full textLaser-plasma acceleration (LPA) [1] is rapidly evolving from proof-of-principle experiments to stable and reliable accelerator operation. The ability of LPA to deliver high-quality, high-energy electron bunches in a compact setup has been demonstrated in numerous experiments over the last two decades [2]–[4]. An important next step towards reliable accelerator operation is to increase the repetition rate from the current few Hertz to the kHz range. The main limitation of the repetition rate is currently the driving laser systems, which need to deliver pulses with ~100 TW peak power and excellent spatio-temporal pulse quality, which becomes increasingly difficult at high repetition rates
Unlearning with Partial Label Learning
No full textMachine Unlearning describes the challenge of forgetting data points that were used for an initial training of a machine learning model. Data privacy concerns as well as safety of sensitive learning data are the driving motivation for the emergence of this field. The special case of class unlearning is a challenge, as an entire class is to be unlearned without affecting the accuracy of potentially very similar other classes. We propose a novel method for class unlearning that is robust, efficient and can be applied without having access to the full initial training data. The approach is based on disambiguation-free partial label learning and can be understood as a stabilized version of gradient ascent. Furthermore, we show how this approach can be applied to training data with negative quasiprobabilities which is a problem encountered in high energy physics
Physical Security of Lattice-Based Schemes in Embedded Devices
No full textThe rise of quantum computing threatens today’s cryptography, making post-quantum schemes essential. Yet when deployed on embedded devices, they face another risk: side-channel attacks. By monitoring power use or electromagnetic signals, attackers can extract keys from a car’s control unit, a smart card, or a phone’s secure element. This talk shows why such leakage must be addressed and how lattice-based schemes perform in practice
Search for the production of a Higgs boson in association with a single top quark in pp collisions at TeV with the ATLAS detector
No full textA search for the production of a Higgs boson in association with a single top quark, tH, is presented. The analysis uses proton-proton collision data corresponding to an integrated luminosity of 140 fb at a centre-of-mass energy of 13 TeV, collected by the ATLAS detector at the LHC. The search targets Higgs-boson decays into , WW, ZZ, and ττ, accompanied by an isolated lepton (electron or muon) from the top-quark decay. Multivariate techniques are employed to enhance the separation between signal and background processes. The observed signal strength, μ, defined as the ratio between the measured cross-section and the predicted Standard Model value, is μ = 8.1 ± 2.6 (stat.) ± 2.0 (syst.). The significance of the observed (expected) signal above the background-only expectation is 2.8 (0.4) standard deviations. The corresponding observed (expected) upper limit at the 95% confidence level on the tH cross-section is found to be 13.9 (6.1) times the value predicted by the Standard Model. An interpretation with an inverted sign of the top-quark Yukawa coupling is performed, and the signal strength and corresponding limit are reported.[graphic not available: see fulltext
Software and computing for Run 3 of the ATLAS experiment at the LHC
No full textThe ATLAS experiment has developed extensive software and distributed computing systems for Run 3 of the LHC. These systems are described in detail, including software infrastructure and workflows, distributed data and workload management, database infrastructure, and validation. The use of these systems to prepare the data for physics analysis and assess its quality are described, along with the software tools used for data analysis itself. An outlook for the development of these projects towards Run 4 is also provided
Climbing to the Top of the ATLAS 13 TeV data
No full textThe large amount of data recorded with the ATLAS detector at the Large Hadron Collider, corresponding to 140 fb of pp collisions at a centre-of-mass energy of =13TeV, has brought our knowledge of the top quark to a higher level. The measurement of the top–antitop quark pair-production cross-section has reached a precision of 1.8% and the cross-section was measured differentially up to several TeV in multiple observables including the top-quark transverse momentum and top-quark-pair invariant mass. Single-top-quark production was studied in all production modes. Rare production processes where the top quark is associated with a vector boson, and four-top-quark production, have become accessible and cross-section measurements for several of these processes have reached uncertainties of around 10% or smaller. Innovative measurements of the top-quark mass and properties have also emerged, including the observation of quantum entanglement in the top-quark sector and tests of lepton-flavour universality using top-quark decays. Searches for flavour-changing neutral currents in the top-quark sector have been significantly improved, reaching branching-ratio exclusion limits ranging from 10 to 10. Many of these analyses have been used to set limits on Wilson coefficients within the effective field theory framework
Observation of and search for at near 10.75 GeV
No full textWe present an analysis of the processes , , and with reconstructed from final states in of Belle II data collected at four energy points near the peak of the resonance. Here, is a hypothetical bottomonium-sector partner of the . A signal of is observed with a significance greater than . The central value of the Born cross section at 10.653 GeV is measured to be higher than that at 10.745 GeV, and we find evidence for a possible new state near threshold, with a significance of . No significant signal is observed for or . Upper limits on the Born cross sections for the processes and with are determined