arXiv Physics @arxiv_physics@qoto.org

Since the early 2000s there has existed the meme that "DOOM can run on anything". Whether it be an ATM or a calculator, someone at some point has recompiled DOOM to run on it. Now the quantum computer finally joins the list. More specifically, this project represents the first level of DOOM loosely rewritten using Hadamards and Toffolis which, despite being a universal gate set, has been designed in such a way that it's classically simulable, able to reach 10-20 frames per second on a laptop. The circuit uses 72,376 total qubits and at least 80 million gates, thus it may have use as a benchmark for quantum simulation software.

The detonation behaviors during thermonuclear burning indicate a state of robust hot spot burning and are widely present in astronomical phenomena, such as supernovae. In this work, we propose an analytical model including alpha-particle deposition at the shock front, which significantly lowers the detonation threshold. The new temperature threshold is 13.4 keV for the isochoric ignition and 25.1 keV for the isobaric ignition, both of which are more accessible experimentally. When a shock wave is present, alpha-particle deposition occurs at the high-density shock front instead of the cold fuel, accelerating the burning wave by approximately 20%. To further validate these findings, we conducted a series of 3D radiation hydrodynamics simulations using finite isochoric hot spots with different fast electron energy. The results reveal a rise in burn-up fraction caused by the detonation wave with a deposited fast electron energy about 8.5 kJ. This work can provide a reference for the realization of fusion energy via fast ignition schemes, such as the double-cone ignition scheme. This work also shows the possibility of studying the detonation in astrophysics with laser driven fast ignition.

This paper presents the principal challenges and opportunities associated with computational biomechanics research. The underlying cognitive control involved in the process of human motion is inherently complex, dynamic, multidimensional, and highly non-linear. The dynamics produced by the internal and external forces and the body's ability to react to them is biomechanics. Complex and non-rigid bodies, needs a lot of computing power and systems to execute however, in the absence of adequate resources, one may rely on new technology, machine learning tools and model order reduction approaches. It is also believed that machine learning approaches can enable us to embrace this complexity, if we could use three arms of ML i.e. predictive modeling, classification, and dimensionality reduction. Biomechanics, since it deals with motion and mobility come with a huge set of data over time. Using computational (Computer Solvers), Numerical approaches (MOR) and technological advances (Wearable sensors), can let us develop computationally inexpensive frameworks for biomechanics focused studies dealing with a huge amount of data. A lot of misunderstanding arises because of extensive data, standardization of the tools to process this, database for the material property definitions, validation and verification of biomechanical models and analytical tools to model various phenomena using computational and modelling techniques. Study of biomechanics through computational simulations can improve the prevention and treatment of diseases, predict the injury to reduce the risk and hence can strengthen pivotal sectors like sports and lifestyle. This is why we choose to present all those challenges and problems associated with biomechanical simulation with complex geometries fail so as to help improve, analysis, performance and design for better lifestyle.

In the realm of PCB and packaging interconnect design, electromagnetic analysis tools have transitioned from optional to essential over the last two decades, as data rates soared beyond 6 Gbps. Today, with standard data rates eclipsing 6 Gbps and reaching thresholds of 224 Gbps, these tools are indispensable for designing reliable interconnects. The goals of the interconnect analysis are simple: identify interconnects that may fail at the target data rate and allow troubleshooting and fixing the problem. The most efficient approach to such pass-fail analysis is the Decompositional Electromagnetic Analysis (DEA). It allows separation of the signal degradation factors for faster analysis and troubleshooting. This paper outlines the basic elements of DEA, discusses conditions for its accuracy and underscores its significance in the future of interconnect design.

Precision space inertial sensors are imperative for Earth geodesy missions, gravitational wave observations, and fundamental physics experiments in space. In these missions, free-falling test masses(TMs) are susceptible to parasitic electrostatic forces and torques, with significant contributions from the interaction between stray electric fields and TM charge. These effects can make up a sizable fraction of the noise budget. Thus, a charge management system(CMS) is essential in high-precise space-based missions. However, the operating environment for space charge control is full of uncertainties and disturbances. TM charge tracking precision is negatively affected by many physical parameters such as external charging rate, quantum yield, UV light power, etc. Those parameters are rarely measured and supposed to vary because of changes in solar activity, temperature, aging of electronic components and so on. The unpredictability and variability of these parameters affects the CMS performance in long-term space missions and must be evaluated or eliminated. This paper presents a simple physics-based model of the discharging process with high charging/discharging rate based on the geometry of inertial sensors. After that, a disturbance observer sliding mode control (DOSMC) is proposed for the CMS with parametric uncertainties and unknown disturbance to maintain the TM charge below a certain level and improve its robustness. The simulation results show that the DOSMC is able to force the system trajectory coincides with the sliding line, which depends neither on the parameters or disturbances. In this way, the DOSMC can effectively ignore the parameter perturbation and external disturbances. The control precision can reach 0.1 mV, which is superior to that of a classic proportional-integral-derivative controller and conventional sliding mode control.

At sub-Kelvin temperatures, two-level systems (TLS) present in amorphous dielectrics source a permittivity noise, degrading the performance of a wide range of devices using superconductive resonators such as qubits or kinetic inductance detectors. We report here on measurements of TLS noise in hydrogenated amorphous silicon (a-Si:H) films deposited by plasma-enhanced chemical vapor deposition (PECVD) in superconductive lumped-element resonators using parallel-plate capacitors (PPCs). The TLS noise results presented in this article for two recipes of a-Si:H improve on the best achieved in the literature by a factor >5 for a-Si:H and other amorphous dielectrics and are comparable to those observed for resonators deposited on crystalline dielectrics.

We propose an analytical approach to solving nonlocal generalizations of the Euler--Bernoulli beam. Specifically, we consider a version of the governing equation recently derived under the theory of peridynamics. We focus on the clamped--clamped case, employing the natural eigenfunctions of the fourth derivative subject to these boundary conditions. Static solutions under different loading conditions are obtained as series in these eigenfunctions. To demonstrate the utility of our proposed approach, we contrast the series solution in terms of fourth-order eigenfunctions to the previously obtained Fourier sine series solution. Our findings reveal that the series in fourth-order eigenfunctions achieve a given error tolerance (with respect to a reference solution) with ten times fewer terms than the sine series. The high level of accuracy of the fourth-order eigenfunction expansion is due to the fact that its expansion coefficients decay rapidly with the number of terms of the series, one order faster than the Fourier series in our examples.

The two-dimensional nanomaterial, hexagonal boron nitride (hBN) was cleanly transferred via a blister-based laser-induced forward-transfer method. The transfer was performed utilizing femtosecond and nanosecond laser pulses for separation distances of ~16 and ~200 micrometers between a titanium donor film deposited on a glass substrate and a silicon/silicon dioxide receiver. Transfer efficiency was examined for isolated laser pulses as well as for series of overlapping pulses and single layer transfer was confirmed. It was found that hBN is transferable for all tested combinations of pulse duration and transfer distances. The results indicate that transfer proceeds via direct stamping for short donor-to-receiver distances while, for the larger distance, the material is ejected from the donor and lands on the receiver. Furthermore, with overlapping pulses, nanosecond laser pulses enable a successful printing of hBN lines while, for fs laser pulses, the Ti film can be locally disrupted by multiple pulses and molten titanium may be transferred along with the hBN flakes. For reproducibility, and to avoid contamination with metal deposits, low laser fluence transfer with ns pulses and transfer distances smaller than the blister height provide the most favourable and reproducible condition.

The extremely narrow natural linewidths of rovibrational energy levels in the molecular hydrogen ion $\textrm{H}_2^{\,+}$, and the prospect of synthesising its antimatter counterpart $\overline{\textrm{H}}_2^{\,-}$, make it a promising candidate for high-precision tests of fundamental symmetries such as Lorentz and CPT invariance. In this paper, we present a detailed analysis of the rovibrational spectrum of the (anti-)hydrogen molecular ion in a low-energy effective theory incorporating Lorentz and CPT violation. The focus is on the spin-independent couplings in this theory, for which the best current bounds come from measurements of the 1S-2S transition in atomic hydrogen and antihydrogen. We show that in addition to the improvement in these bounds from the increased precision of the transition frequencies, potentially reaching 1 part in $10^{17}$, rovibrational transitions have an enhanced sensitivity to Lorentz and CPT violation of $O(m_p/m_e)$ in the proton (hadron) sector compared to atomic transitions.

In this study, we investigate the effects of pre-germinative and post-germinative plasma treatments, applied separately or in combination, to improve maize germination and early seedling development. Pre-germinative treatment consists of priming the seeds with a dry atmospheric plasma (DAP) generated by a dielectric barrier device (DBD), characterized by minimal radiative emission, low electrical power (4 W) and high emissions of O, OH and NO radicals. Post-germinative treatment, known as plasma-activated water (PAW), uses a single-pin electrode device (SPED) to generate a DC discharge that features a power of 126 W and produces large amounts of OH radicals. The resulting PAW, after 5 minutes of SPED treatment, induces a slight acidification and increased concentrations of nitrate ions (from 24 to 250 mg/L), nitrite ions (from less than 0.1 to 56.1 mg/L) and hydrogen peroxide (from 0.3 to 18.5 mg/L). Results indicate that DAP applied on maize seeds for 20 min boosts their germination rate up to 90% (versus only 65% for untreated seeds) while reducing the median germination time by 37.5%. Then, seedling growth monitoring is achieved on control, DAP, PAW and DAP+PAW groups to assess stem length, hypocotyl length, leaf count, collar diameter and fresh/dry mass. The DAP+PAW group shows the most robust growth, demonstrating a synergistic effect of the combined treatments, particularly with significantly longer stem lengths. Additionally, physiological analyses of seedling leaves indicate a decrease in chlorophyll content despite enhanced growth, while fluorescence microscopy reveals a reduction in stomatal density in leaves treated with DAP and PAW, especially in the combined treatment group, potentially impacting photosynthetic efficiency and water regulation.