arXiv subjects

Dominik Kowal

Publications and source records attributed to Dominik Kowal.

4 recordsLinked to original sources

arXiv2026

Tuning light-matter interaction of near-infrared nanoplasmonic scintillators

Nanoplasmonic modification of scintillation has so far been explored mainly in the weak-coupling regime, where changes in the local density of optical states enhance radiative recombination via Purcell-type rate engineering. By contrast, strong light-matter coupling generates hybrid states that modify emission dynamics beyond simple decay-rate acceleration, but its implications for scintillator nanocrystals (NCs) under ionizing radiation remain poorly understood. All of these effects are beneficial for near-infrared scintillators, which are typically slow and have low brightness. Here, we present a quantum-optical framework to investigate how near-infrared scintillator NCs coupled to nanoplasmonic antennas evolve from weak coupling toward strong light-matter coupling. We compare broad- and narrow-antenna platforms with single and periodic Au nanorods and benchmark them against conductive plasmonic antennas based on indium tin oxide and graphene. As representative emitters, we consider wide-band PbS NCs and narrow-band cubic Lu2O3:Er3+ scintillators. The calculations show that the onset of strong-coupling signatures is jointly governed by emitter dephasing and the antenna linewidth, with narrow-band emitters coupled to spectrally narrow antennas providing the most favorable conditions. Among the platforms considered, graphene gives the lowest threshold (g = 4 meV) for observable coherent exchange owing to its ultranarrow antenna linewidth (\k{appa} = 3.5 meV). These results identify near-infrared conductive nanoantennas, particularly graphene-based ones, as promising platforms for accessing hybrid scintillation regimes relevant to radiation detection.

physics.optics↗

arXiv2025

Cation Engineering of Cu-Doped CsPbI3: Lead Substitution and Dimensional Reduction for Improved Scintillation Performance

To date, inorganic halide perovskite nanocrystals show promising contributions in emerging luminescent materials due to their high tolerance to defects. In particular, the development of cesium lead iodide (CsPbI3) has shown its efficiency for light-harvesting properties. However, further implementation is hindered due to the toxicity of the lead content. Therefore, in this study, we introduced Cu atoms to partially substitute Pb atoms (5% Cu) in the CsPbI3 lattice as a solution to reduce Pb toxicity. A partial lead material is substituted using Cu displays a larger Stokes shift (-67 nm) compared to the pristine, and resulted doped CsPbI3 not undergo the undesired self absorption. An outcome is focused on the champion of fast-component (tau_1) decay time ~0.6 ns. Temperature-dependent radioluminescence outlines an incremental change in the emission intensity is marginally centered at 713 +- 16 nm, which indicates Cu-doped CsPbI3 is not greatly affected by temperature. In addition, we report that the light yield (LY) pristine CsPbI3 after doping is increased to 3.0 +- 0.8 photons/keV. Our work provides physical insights into a tunable scintillation property using transition metal doping toward lead-free based scintillating perovskites.

cond-mat.mtrl-sci↗

arXiv2024

Scaling Up Purcell-Enhanced Self-Assembled Nanoplasmonic Perovskite Scintillators into the Bulk Regime

Scintillators convert high-energy radiation into detectable photons and play a crucial role in medical imaging and security applications. The enhancement of scintillator performance through nanophotonics and nanoplasmonics, specifically using the Purcell effect, has shown promise but has so far been limited to ultrathin scintillator films because of the localized nature of this effect. This study introduces a method to expand the application of nanoplasmonic scintillators to the bulk regime. By integrating 100-nm-sized plasmonic spheroid and cuboid nanoparticles with perovskite scintillator nanocrystals, we enable nanoplasmonic scintillators to function effectively within bulk-scale devices. We experimentally demonstrate power and decay rate enhancements of up to (3.20 $\pm$ 0.20) and (4.20 $\pm$ 0.31) folds for plasmonic spheroid and cuboid nanoparticles, respectively, in a 5-mm thick CsPbBr$_{3}$ nanocrystal-polymer scintillator at RT. Theoretical modeling also predicts similar enhancements of up to (2.26 $\pm$ 0.31) and (3.02 $\pm$ 0.69) folds for the same nanoparticle shapes and dimensions. Moreover, we demonstrate a (2.07 $\pm$ 0.39) fold increase in light yield under $^{241}$Am $\gamma$-excitation. These findings provide a viable pathway for utilizing nanoplasmonics to enhance bulk scintillator devices, advancing radiation detection technology.

physics.optics↗

arXiv2023

The Nanoplasmonic Purcell Effect in Ultrafast and High-Light-Yield Perovskite Scintillators

The development of X-ray scintillators with ultrahigh light yields and ultrafast response times is a long sought-after goal. In this work, we theoretically predict and experimentally demonstrate a fundamental mechanism that pushes the frontiers of ultrafast X-ray scintillator performance: the use of nanoscale-confined surface plasmon polariton modes to tailor the scintillator response time via the Purcell effect. By incorporating nanoplasmonic materials in scintillator devices, this work predicts over 10-fold enhancement in decay rate and 38% reduction in time resolution even with only a simple planar design. We experimentally demonstrate the nanoplasmonic Purcell effect using perovskite scintillators, enhancing the light yield by over 120% to 88 $\pm$ 11 ph/keV, and the decay rate by over 60% to 2.0 $\pm$ 0.2 ns for the average decay time, and 0.7 $\pm$ 0.1 ns for the ultrafast decay component, in good agreement with the predictions of our theoretical framework. We perform proof-of-concept X-ray imaging experiments using nanoplasmonic scintillators, demonstrating 182% enhancement in the modulation transfer function at 4 line pairs per millimeter spatial frequency. This work highlights the enormous potential of nanoplasmonics in optimizing ultrafast scintillator devices for applications including time-of-flight X-ray imaging and photon-counting computed tomography.

physics.optics↗