physics
physics
11-26 00:00
arXiv:2511.19442v1 Announce Type: new Abstract: Creating software dedicated to simulation is essential for teaching and research in Science, Technology, Engineering, and Mathematics (STEM). Physics lecturing can be more effective when digital twins are used to accompany theory classes. Research in physics has greatly benefited from the advent of modern, high-level programming languages, which facilitate the implementation of user-friendly code. Here, we report our own Python-based software, the gr-orbit-toolkit, to simulate orbits in classical and general relativistic scenarios. First, we present the ordinary differential equations (ODEs) for classical and relativistic orbital accelerations. For the latter, we follow a post-Newtonian approach. Second, we describe our algorithm, which numerically integrates these ODEs to simulate the orbits of small-sized objects orbiting around massive bodies by using Euler and Runge-Kutta methods. Then, we study a set of sample two-body models with either the Sun or a black hole in the center. Our simulations confirm that the orbital motions predicted by classical and relativistic ODEs drastically differ for bodies near the Schwarzschild radius of the central massive body. Classical mechanics explains the orbital motion of objects far away from a central massive body, but general relativity is required to study objects moving at close proximity to a massive body, where the gravitational field is strong. Our study on objects with different eccentricities confirms that our code captures relativistic orbital precession. Our convergence analysis shows the toolkit is numerically robust. Our gr-orbit-toolkit aims at facilitating teaching and research in general relativity, so a comprehensive user and developer guide is provided in the public code repository.
astro-ph.imgr-qcphysics.ed-ph
physics
physics
11-26 00:00
arXiv:2511.19520v1 Announce Type: new Abstract: Understanding how glioblastoma (GBM) emerges from initially healthy glial tissue requires models that integrate bioelectrical, metabolic, and multicellular dynamics. This work introduces an ASAL-inspired agent-based framework that simulates bioelectric state transitions in glial cells as a function of mitochondrial efficiency (Meff), ion-channel conductances, gap-junction coupling, and ROS dynamics. Using a 64x64 multicellular grid over 60,000 simulation steps, we show that reducing Meff below a critical threshold (~0.6) drives sustained depolarization, ATP collapse, and elevated ROS, reproducing key electrophysiological signatures associated with GBM. We further apply evolutionary optimization (genetic algorithms and MAP-Elites) to explore resilience, parameter sensitivity, and the emergence of tumor-like attractors. Early evolutionary runs converge toward depolarized, ROS-dominated regimes characterized by weakened electrical coupling and altered ionic transport. These results highlight mitochondrial dysfunction and disrupted bioelectric signaling as sufficient drivers of malignant-like transitions and provide a computational basis for probing the bioelectrical origins of oncogenesis.
q-bio.ncphysics.bio-phcs.ne
physics
physics
11-26 00:00
arXiv:2511.19533v1 Announce Type: new Abstract: We experimentally demonstrate a novel interferometric architecture for next-generation gravity missions, featuring a laser ranging interferometer (LRI) that enables monoaxial transmission and reception of laser beams between two optical benches with a heterodyne frequency of 7.3 MHz. Active beam steering loops, utilizing differential wavefront sensing (DWS) signals, ensure co-alignment between the receiving (RX) beam and the transmitting (TX) beam. With spacecraft attitude jitter simulated by hexapod-driven rotations, the interferometric link achieves a pointing stability below 10 urad/$\mathrm{\sqrt{Hz}}$ in the frequency range between 2 mHz and 0.5 Hz, and the fluctuation of the TX beam's polarization state results in a reduction of 0.14\% in the carrier-to-noise-density ratio over a 15-hour continuous measurement. Additionally, tilt-to-length (TTL) coupling is experimentally investigated using the periodic scanning of the hexapod. Experimental results show that the on-axis LRI enables the inter-spacecraft ranging measurements with nanometer accuracy, making it a potential candidate for future GRACE-like missions.
physics.opticsphysics.ins-detastro-ph.im
physics
physics
11-26 00:00
arXiv:2511.19539v1 Announce Type: new Abstract: Side-scan sonar (SSS) imagery is widely used for seafloor mapping and underwater remote sensing, yet the measured intensity is strongly influenced by seabed reflectivity, terrain elevation, and acoustic path loss. This entanglement makes the imagery highly view-dependent and reduces the robustness of downstream analysis. In this letter, we present PhysDNet, a physics-guided multi-branch network that decouples SSS images into three interpretable fields: seabed reflectivity, terrain elevation, and propagation loss. By embedding the Lambertian reflection model, PhysDNet reconstructs sonar intensity from these components, enabling self-supervised training without ground-truth annotations. Experiments show that the decomposed representations preserve stable geological structures, capture physically consistent illumination and attenuation, and produce reliable shadow maps. These findings demonstrate that physics-guided decomposition provides a stable and interpretable domain for SSS analysis, improving both physical consistency and downstream tasks such as registration and shadow interpretation.
cs.cvphysics.ao-ph
physics
physics
11-26 00:00
arXiv:2511.19541v1 Announce Type: new Abstract: Space-time metamaterials are redefining wave engineering by enabling fully dynamic four-dimensional control of electromagnetic fields, allowing simultaneous manipulation of frequency, amplitude, momentum, and propagation direction. This unified functionality moves well beyond reciprocity-breaking mechanisms, marking a fundamental transition from static media to polychromatic, energy-efficient wave processors. This article establishes dispersion engineering as the core design paradigm for these dynamic systems. We show that the dispersion relation, linking frequency and wavenumber, serves as a master blueprint governing exotic wave phenomena such as nonreciprocity, beam splitting, asymmetric frequency conversion, amplification, spatial decomposition, and momentum bandgaps. By analyzing analytical dispersion surfaces and isofrequency contours in subluminal, luminal, and superluminal modulation regimes, we reveal how tailored spatiotemporal modulation orchestrates controlled energy flow among harmonic modes. We further demonstrate how this framework directly informs practical device operation, highlighting advanced implementations including angular-frequency beam multiplexing in superconducting Josephson junction arrays. Combining insights from wave theory, numerical modeling, and experimental realization, this work provides a comprehensive roadmap for leveraging dispersion engineering to design next-generation metamaterials for wireless communication, quantum technologies, and integrated photonics.
physics.opticsphysics.app-ph
physics
physics
11-26 00:00
arXiv:2511.19545v1 Announce Type: new Abstract: Fully harnessing the vast design space enabled by metamaterials to control electromagnetic (EM) fields remains an open problem for researchers. Inverse-design techniques have shown to best exploit the degrees of freedom available in design, resulting in high-performing systems for wireless communications, sensing and analog signal processing. Nonetheless, fundamental yet powerful properties of metamaterials are still to be revealed. In this paper, we introduce the concept of Perfectly Matched Metamaterials (PMMs). PMMs are passive, inhomogeneous media that perform purely refractive field transformations under different excitations. Their advantage lies in their simplicity, reflectionless behavior and suitability for both analytical and numerical design methods. Unlike Transformation Optics, PMM-based designs are devoid of coordinate transformations. Anisotropic unit cells are configured to control EM fields in a true-time delay manner. Simple analytical designs are reported which demonstrate the broadband capability of PMM devices. Proposed PMMs may find application in wideband beamforming and analog computing, realizing functionalities such as spatial filtering and signal pre-processing.
physics.opticsphysics.app-ph
physics
physics
11-26 00:00
arXiv:2511.19559v1 Announce Type: new Abstract: From al-Sufi's tenth-century observation of the Andromeda Galaxy as a "little cloud" to contemporary space missions, Islamic astronomy represents a millennium-spanning tradition of innovation and knowledge. This study traces its trajectory through three phases: the Golden Age (8th to 15th centuries), when scholars such as al-Biruni, al-Battani, and Ibn Sina developed instruments, cataloged the heavens, and refined theories that later influenced Copernicus; a period of decline (late 15th to 17th centuries), shaped by political fragmentation, economic shifts, and the delayed adoption of technologies such as printing and the telescope; and today's revival, marked by observatory collaborations, Olympiad successes, and emerging space programs in Morocco, Iran, Turkey, the UAE, and Saudi Arabia. This comparative analysis with Chinese and European scientific traditions shows how Islamic astronomy provided a vital link in the global history of science, transmitting mathematical rigor, observational methods, and Arabic star names that are still used today. The contemporary resurgence signals the potential for renewed contributions to astrophysics, provided that it is supported by regional observatory networks, space-based research initiatives, and educational frameworks that integrate historical heritage with modern computational science.
physics.hist-phastro-ph.im
physics
physics
11-26 00:00
arXiv:2511.19564v1 Announce Type: new Abstract: Solar energy has enormous potential because there is a worldwide need to meet energy demands. Depleting non-renewable energy resources, increasing carbon emissions, and other environmental effects concern the scientific community to develop an alternative approach to electricity production. In this article, we present the study of a solar-powered Organic Rankine cycle considering Indian climatic conditions. Initially, we scrutinized seven working fluids and assessed their performance in the ORC at an evaporator pressure range of 9-30 bar and a mass flow rate range of 0.2 kg/s to 4.5 kg/s. For a fixed sink temperature of 298 K, we evaluate the system using four different power ratings of 2, 20, 50, and 100 kW based on four different source temperatures of 423 K, 403 K, 383 K, and 363 K. We estimate the system cost for each working fluid in each scenario separately. Our findings suggest that R 1233zd(E) is the optimum performing working fluid based on cost, cost-effectiveness, and environmental friendliness. We also notice that the estimated system scale cost is very competitive and could be a great alternative to the technologies already on the Indian market.
physics.soc-phphysics.app-ph
physics
physics
11-26 00:00
arXiv:2511.19638v1 Announce Type: new Abstract: Data-driven weather prediction models implicitly assume that the statistical relationship between predictors and targets is stationary. Under anthropogenic climate change, this assumption is violated, yet the structure of the resulting concept drift remains poorly understood. Here we introduce concept drift of simple forecast models as a diagnostic of atmospheric reorganisation. Using ERA5 reanalysis, we quantify drift in spatially explicit linear models of daily mean sea-level pressure and 2\,m temperature. Models are trained on the 1950s and 2000s and evaluated on 2020 tp 2024; their performance difference defines a local, interpretable drift metric. By decomposing errors by frequency band, circulation regime and region, and by mapping drift globally, we show that drift is dominated by low-frequency variability and is strongly regime-dependent. Over the North Atlantic-European sector, low-frequency drift peaks in positive NAO despite a stable large-scale NAO pattern, while Western European summer temperature drift is tightly linked to changes in land-atmosphere coupling rather than mean warming alone. In winter, extreme high-pressure frequencies increase mainly in neutral and negative NAO, whereas structural drift is concentrated in positive NAO and Alpine hotspots. Benchmarking against variance-based diagnostics shows that drift aligns much more with changes in temporal persistence than with changes in volatility or extremes. These findings demonstrate that concept drift can serve as a physically meaningful diagnostic of evolving predictability, revealing aspects of atmospheric reorganisation that are invisible to standard deviation and storm-track metrics.
stat.apphysics.ao-ph
physics
physics
11-26 00:00
arXiv:2511.19702v1 Announce Type: new Abstract: We implement a feedback protocol to suppress the AC Stark shift in a two-photon rubidium optical frequency reference, reducing its sensitivity to optical power variations by a factor of 1000. This method alleviates the tradeoff between short-term and long-term stability imposed by the AC Stark shift, enabling us to simultaneously achieve instabilities of $3\times10^{-14}$ at 1 s and $2\times10^{-14}$ at $10^4$ s. We also quantitatively describe, and experimentally explore, a stability limit imposed on clocks using this method by frequency noise on the local oscillator.
physics.atom-phphysics.app-ph
physics
physics
11-26 00:00
arXiv:2511.19738v1 Announce Type: new Abstract: Dust layers have already been reported to have negative impacts on the radiation budget of the atmosphere. But the questions are: How does the atmospheric surface temperature change during a dust outbreak, and what is its temporal correlation with variations of the dust outbreak strength? We investigated these at selected AERONET sites, including Bahrain, IASBS, Karachi, KAUST Campus, Kuwait University, Lahore, Mezaira, Solar Village, in Southwest Asia, and Dushanbe in Central Asia, using available data from 1998 to 2024. The aerosol optical depth at 870 nm and the temperature recorded at each site are taken as measures of dust outbreak strength and atmospheric surface temperature, respectively. The Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model and the aerosol optical depths recorded by the Moderate Resolution Imaging Spectroradiometers (MODIS) on board the Aqua and Terra satellites are used to specify the sources of the dust outbreaks. Our investigations show that in most cases, the temperature decreases during a dust outbreak, but in a considerable number of cases, the temperature rises. Temperature changes are mostly less than 5 {\deg}C. We found that a dust outbreak may affect the temperature even up to two days after its highest intensity time. This effect is more profound at sites far from large dust sources, such as IASBS in northwest Iran. For sites that are located on either a dust source or very close to it, the temperature and dust optical depth vary almost synchronously.
physics.opticsastro-ph.epphysics.ao-ph
physics
physics
11-26 00:00
arXiv:2511.19807v1 Announce Type: new Abstract: We present an investigation into beam steering and radiation emission by sub-GeV electrons traversing bent silicon crystals. Using 855, 600, and 300~MeV electron beams at the Mainz Microtron (MAMI), we explored orientational coherent effects and particle dynamics in a 15~$\mu$m-thick crystal bent along the (111) planes. Combined experimental and simulation analyses enabled the classification and quantitative assessment of the contributions from channeling, dechanneling, rechanneling, and volume capture to both beam deflection and radiation emission. Crystal steering remained effective even at 300~MeV, with measured channeling efficiencies exceeding 50\%, a record at such low energy. Channeling and volume reflection enhanced radiation emission by up to a factor of six compared to the misaligned orientation, highlighting strong orientational coherence effects in the sub-GeV regime. These findings confirm the feasibility of using bent crystals for efficient beam manipulation and high-intensity photon generation at low energies, supporting the development of novel light sources and beam control strategies at accelerator facilities operating in this energy range.
physics.acc-phhep-ex
physics
physics
11-26 00:00
arXiv:2511.19815v1 Announce Type: new Abstract: In the context of global climate change, geological materials are increasingly destabilized by water flow and infiltration. We study the creeping dynamics of a densely monitored landslide in Western Norway to decipher the role of fluid flow in destabilizing this landslide. In {\AA}knes, approximately 50 million cubic meter of rock mass continuously creeps over a shear zone made of rock fragments, with seasonal accelerations that strongly correlate with rainfall. In this natural laboratory for fluid-induced frictional creep, unprecedented monitoring equipment reveals low fluid pressure across the shear zone, thereby challenging the dominant theory of fluid-driven instability in landslides. Here, we show that a generic micromechanical model can disentangle the effects of fluid flow from those of fluid pressure, and demonstrate that seepage forces applied by channelized flow along the shear zone are the main driver of creep accelerations. We conclude by discussing the significance of seepage forces, the implications for hazard mitigation and the broader applicability of our model to various geological contexts governed by friction across saturated shear zones.
physics.geo-phphysics.flu-dyn
physics
physics
11-26 00:00
arXiv:2511.19817v1 Announce Type: new Abstract: The Scintillating Bubble Chamber (SBC) Collaboration is designing a new generation of low background, noble liquid bubble chamber experiments with sub-keV nuclear recoil threshold. These experiments combine the electronic recoil blindness of a bubble chamber with the energy resolution of noble liquid scintillation, and maintain electron recoil discrimination at higher degrees of superheat (lower nuclear recoil thresholds) than Freon-based bubble chambers. A 10-kg liquid argon bubble chamber has the potential to set world leading limits on the dark matter nucleon cross-section for $O(\mathrm{GeV}/c^{2})$ masses, and to perform a high statistics coherent elastic neutrino nuclear scattering measurement with reactor neutrinos. This work presents a detailed calibration plan to measure the detector response of these experiments, combining photoneutron scattering with two new techniques to induce sub-keV nuclear recoils: nuclear Thomson scattering and thermal neutron capture.
physics.ins-dethep-exnucl-ex
physics
physics
11-26 00:00
arXiv:2511.19821v1 Announce Type: new Abstract: Evacuating the powder trapped inside the complex cavities of Triply Periodic Minimal Surface (TPMS) structures remains a major challenge in metal-powder-based additive manufacturing. The Discrete Element Method offers valuable insights into this evacuation process, enabling the design of effective de-powdering strategies. In this study, we simulate gravity-driven evacuation of trapped powders from inside unit cells of various TPMS structures. We systematically investigate the role of cohesive energy density in shaping the discharge profile. Overall, we conclude that the Schwarz-P and Gyroid topologies enable the most efficient powder evacuation, remaining resilient to cohesion-induced flow hindrance. Furthermore, for the two unit cells, we analyse detailed kinematics and interpret the results in relation to particle overlaps and contact force distributions.
cond-mat.softphysics.comp-ph
physics
physics
11-26 00:00
arXiv:2511.19831v1 Announce Type: new Abstract: Quantum sensors based on the nitrogen-vacancy (NV) center in diamond are leading platforms for high-sensitivity magnetometry with nanometer-scale resolution. State-of-the-art implementations, however, typically rely on bulky free-space optics or sacrifice spatial resolution to achieve high sensitivities. Here, we realize an integrated platform that overcomes this trade-off by fabricating monolithic whispering-gallery-mode cavities from a diamond chip containing a high density of NV centers and by evanescently coupling excitation to and photoluminescence from the cavity using a tapered optical fiber. Employing a lock-in-amplified Ramsey magnetometry scheme, we achieve a photon-shot-noise-limited DC sensitivity of $58\,\text{nT}/\sqrt{\text{Hz}}$ -- the best sensitivity reported to date for a nanofabricated cavity-based magnetometer. The microscopic cavity size enables sub-micrometer-scale spatial resolution and low-power operation, while fiber-coupling provides a path to scalable on-chip integration. Arrays of such sensors could enable NV-NMR spectroscopy of sub-nanoliter samples, new magnetic-gradient imaging architectures, and compact biosensing platforms.
physics.opticsquant-ph
physics
physics
11-26 00:00
arXiv:2511.19459v1 Announce Type: new Abstract: Community Supported Agriculture (CSA) has been recognized globally as a promising framework that embeds agriculture within social relations, yet its diffusion remains limited in contexts such as Japan. Existing studies have largely focused on either consumer or producer participation in isolation, offering fragmented insights and leaving unexplored how their reciprocal processes jointly shape CSA communities. This study addresses this gap by integrating the trajectories of both groups into a comprehensive account of CSA community formation. Drawing on semi-structured interviews with ten CSA producers and ten consumers, we employed the Modified Grounded Theory Approach (M-GTA) to inductively theorize processes of participation and practice. The analysis showed that producers advance CSA through internal adjustments and sense-making to cope with uncertainties, while consumers are guided by life events, practical skills, and prior purchasing experiences toward participation. Synthesizing these insights, we propose a six-phase model of CSA community formation, dispersed interest, awareness, interest formation, motivation, practice, and co-creative continuation, that demonstrates how producers, consumers, and intermediaries interact across stages. The model highlights the pivotal role of key players in sustaining engagement and provides a new perspective for institutionalizing CSA as a durable component of sustainable food systems.
physics.soc-ph
physics
physics
11-26 00:00
arXiv:2511.19507v1 Announce Type: new Abstract: Understanding the economic impacts of the placement of electric vehicle charging stations (EVCSs) is crucial for planning infrastructure systems that benefit the broader community. Theoretical models have been used to predict human behavior during charging events, however, these models have often neglected the complexity of trip patterns, and have underestimated the real-world impacts of such infrastructure on the local economy. In this paper, we design a quasi-experiment using mobile phone GPS location and EVCS deployment history data to analyze the causal impact of EVCS placement on visitation patterns to businesses. More specifically, we leverage the staggered placement of EVCSs in New York City and California Bay Area to match treated and control businesses that share similar characteristics including the business sector, location, and pre-treatment visitation count. By comparing three alternative matching strategies, we show that staggered adoption avoids selecting controls from non-treated clusters, and yields greater spatial overlap in dense urban areas. We find that EVCS installations significantly increase customer traffic, with effects concentrated in recreational venues in New York City and routine destinations such as groceries, pharmacies, and cafes in California Bay Area. Our results suggest that the economic spillovers of EVCSs vary across urban contexts and highlight the effectiveness of leveraging the staggered nature of adoption timings for evaluating infrastructure impacts in heterogeneous urban environments.
physics.soc-ph
physics
physics
11-26 00:00
arXiv:2511.19547v1 Announce Type: new Abstract: We first described the utero-placental pump phenomenon, in utero, in 2020. We have recruited 36 healthy pregnant women to undergo magnetic resonance imaging (MRI) between 29 and 42 weeks of pregnancy to further explore this occurrence in a single centre prospective observational study. Participants had fetal ultrasound to confirm normal growth. Dynamic MRI was acquired for between 15 and 32 minutes using respiratory triggered, multi-slice, single shot, gradient echo, echo planar imaging covering the whole uterus. All participants had a live birth of a healthy baby weighing over the 10th centile for gestational age and no conditions associated with placental dysfunction e.g. pre-eclampsia. There were no cases of severe maternal or fetal villous malperfusion on placental histopathology. Visible contractions were recorded for all participants who completed MRI scans. Contractions involving a decrease in placental volume >10% were classified as either placental or uterine by visual observation. Placental contractions occurred more frequently than uterine contractions (p=0.0061), were associated with a larger increase in the surface area of the uterine wall not covered by the placenta (p=0.0015), sphericity of the placenta(p<0.0001) and longer durations (p=0.0151). Contractions led to an increase in the MRI parameter R2* in the placenta. There was large variation both between participants and between contractions from the same individual, in terms of the time course and features of contractions. Rate, duration and other features of contractions did not apparently change across the gestational age range studied, although the largest fractional volume changes were detected at early gestation. We found that placental contractions occurred in at least 60% of our healthy pregnant population with a median frequency of 2 per hour and median duration of 2.4 minutes.
physics.med-ph
physics
physics
11-26 00:00
arXiv:2511.19571v1 Announce Type: new Abstract: The notion of an infinite electromagnetic self energy of point charges (presumably electrons) is accepted by many electromagnetic textbooks. See, for instance,\cite{jdj,dg,rf}. However, each of these sources acknowledge that they don't understand that result. In this paper, we show that electrons must be point particles with no electromagnetic self energy.
physics.class-ph
physics
physics
11-26 00:00
arXiv:2511.19658v1 Announce Type: new Abstract: The Proton Improvement Plan II (PIP-II) project is a vital upgrade to the Fermilab accelerator complex. The magnet pulse rate of the PIP-II Injection system requires an increase from the current rate of 15 Hz to 20 Hz as well as a roughly 30% increase in the magnetic field of the new Orbital Bump (ORBUMP) pulsed dipole magnets in the Booster. The ORBUMP magnet mechanical design is presented in this paper. The ORBUMP magnet is secured in a vacuum box and the core is made up of 0.127 mm thick, low carbon steel laminations with a C-5 inorganic magnesium phosphate coating. The core is clamped using external tie bars welded to the core end plates. ANSYS Finite Element Analysis (FEA) was used to evaluate the clamping design to minimize the deflection of the core post welding of the tie bars. The water-cooled, single turn coil, which shapes the magnetic field by acting as the pole tips, is critical for the integrated field homogeneity. The coil manufacturing tolerances and fabrication techniques were evaluated to ensure the magnetic properties of the magnet could be obtained. The coil is electrically isolated from the core using virgin Polyether ether ketone (PEEK) insulating material in the gap. An investigation into the high voltage performance of the virgin PEEK insulator was conducted via partial discharge testing using a 1:1 scale sample.
physics.acc-ph
physics
physics
11-26 00:00
arXiv:2511.19772v1 Announce Type: new Abstract: The Fermilab Accelerator Science and Technology (FAST) Facility at FNAL is a dedicated research and development center focused on advancing particle accelerator technologies for future applications worldwide. Currently, a key objective of FAST Operations is to commission the 2.5 MeV IOTA Proton Injector (IPI) and enable proton injection into the Integrable Optics Test Accelerator (IOTA) storage ring. The low and medium-energy sections of the IPI include four frame-style dipole trims and two multi-function correctors with independently controlled coils, requiring readout of 32 analog channels for current and voltage monitoring in total. To reduce cost and optimize rack space within the PLC-based control system, a 32-to-4 analog signal multiplexing system was designed and implemented. This system enables real-time readback of excitation parameters from all magnetic correctors. This paper presents the design, construction, implementation, and performance of the multiplexing system.
physics.acc-ph
physics
physics
11-26 00:00
arXiv:2511.19786v1 Announce Type: new Abstract: The mechanisms governing molecular photophysics under electronic strong coupling (ESC) remain elusive to date. Here, we use ultrafast pump-probe spectroscopy to study the nonradiative excited state relaxation dynamics of chlorin e6 trimethyl ester (Ce6T) under strong coupling of its transition from the electronic ground state to the Qy band. We use dichroic Fabry-P\'erot cavities to provide a transparent spectral window in which we can directly track the excited state population following optical pumping of either the strongly-coupled Qy band or the higher-lying B band. This scheme circumvents many of the optical artifacts inherent in ultrafast cavity measurements and allows for facile comparison of strongly-coupled measurements with extracavity controls. We observe no significant changes in excited state lifetimes for any optical pumping schemes or cavity coupling conditions considered herein. These results suggest that Ce6T exhibits identical photophysics under ESC and in free space, presenting a new data point for benchmarking emerging theories for cavity photochemistry.
physics.chem-ph
physics
physics
11-26 00:00
arXiv:2511.19804v1 Announce Type: new Abstract: The dual-fiber optical trap, owing to its high sensitivity and facile miniaturization, holds significant actual application value in fields such as high-precision metrology of mechanical quantities and biological manipulation. The positional stability of the trapped particle is pivotal to system performance, directly setting the measurement noise floor and operational precision. In this work, we observe bistability and hysteresis in the axial equilibrium position of a 10-um diameter SiO2 microsphere. This bistability arises from optical interference between the fiber ends and the microsphere, creating multiple potential wells. Experimental results demonstrate that the microsphere's transition rate can be effectively modulated through precise control of the trapping laser power. Furthermore, the incorporation of transverse misalignment has effectively eradicated bistability, thereby substantially improving positional stability throughout the entire optical trapping region. This suppression successfully reduced the system's residual positional uncertainty to the thermal noise limit. Consequently, this research will enhance the precision of microparticle manipulation and the sensitivity of sensing in dual-fiber optical trap systems.
physics.optics