Related papers: Photon avalanche up-conversion in NdAl$_3$(BO$_3$)…
In the anti-Stokes excitation of trivalent rare-earth ions (RE3+), the excitation photons energy is smaller than that of a given absorption transition, and the energy mismatch can be compensated by phonons annihilation from the host…
We investigate the role of the Nd3+ content on the PA characteristics in NdxY1.00-xAl3(BO3)4 particles with x ranging from 0.05 to 1.00. It is known that the replacement of Y3 by Nd3+ into the YAl3(BO3)4 crystalline structure can introduce…
Photon avalanching nanoparticles (ANPs) exhibit extremely nonlinear upconverted emission valuable for sub-diffraction imaging, nanoscale sensing, and optical computing. Avalanching has been demonstrated with Tm3+, Nd3+ or Pr3+-doped…
Atomic negative ions are fragile quantum systems in which correlation among the valence electrons plays a very important role. For doubly excited states correlation becomes dominant. Photodetachment is the process where a negative ion…
Tandem mass spectroscopy ($\textrm{MS}^2$) combined with single photon excitation in the VUV range (photon energy 4.5-9 eV) was performed on protonated uracil ($\textrm{UraH}^{+}$) and uridine ($\textrm{UrdH}^{+}$). The precursor ions with…
Polarized absorption spectra and magnetic circular dichroism (MCD) spectra of Nd0.5Gd0.5Fe3(BO3)4 single crystal were measured in the range of 10000 - 21000 cm-1. The absorption spectra were studied as a function of temperature in the range…
Initiating impact ionization of avalanche breakdown essentially requires applying a high electric field in a long active region, hampering carrier-multiplication with high gain, low bias and superior noise performance. Here we report the…
We characterize spectroscopic and coherence properties of the 1451.37 nm excited-state zero-phonon line (ZPL) between the $^{3}F_{4}$ and the $^{3}H_{4}$ manifolds of a thulium-doped yttrium aluminum perovskite (Tm$^{3+}$:YAlO$_3$) crystal…
The photodissociation dynamics of N$_3^+$ excited from its $^3 \Sigma_{\rm g}^{-}$ ground to the first excited singlet and triplet states is investigated. Three dimensional potential energy surfaces for the $^1$A$'$, $^1$A$''$, and $^3$A$'$…
We investigate theoretically a nuclear excitation mechanism involving absorption of non-resonant photons leveraged by the coupling to the atomic shell. The nuclear non-resonant photoexcitation is assisted by electron recombination which…
We investigate the excitation of a three-level ladder-type atom by a unidirectional field with a pair of indistinguishable photons. Starting from an analytical expression for the two-photon absorption probability, we determine the…
Topological semimetals with protected surface states mark a new paradigm of research beyond the early landmarks of band-structure engineering, allowing fabrication of efficient catalyst to harness the rich metallic surface states to…
Absorption, excitation and emission spectra of cadmium fluoride crystals doped with rare-earth ions were investigated. In contrast to alkaline-earth fluorides the absorption spectra due to 4f - 5d transitions of Ce$^{3+}$, Pr$^{3+}$ and…
We revisit the photoabsorption from the ground state of Na, ending below and above the ionization threshold, with special emphasis on the shape of the photoionization cross section around the Cooper minimum. The present treatment, using a…
Bare reverse biased silicon photodiodes were exposed to 3eV He+, Ne+, Ar+, N2+, N+ and H2O+ ions. In all cases an increase of the reverse current through the diode was observed. This effect and its dependence on the ionization energy of the…
We describe numerically the ionization process induced by linearly and circularly polarized XUV attosecond laser pulses on an aligned atomic target, specifically, the excited state…
The excitation of nitromethane CH$_3$NO$_2$, which is an important propellant and prototypic molecule for large class of explosives, has been investigated by electron impact and subsequent emission of photons in the UV-VIS spectral region…
We report, for the first time, the luminescence property of the hydroxyl group surface functionalized quantum dots (QDs) and nanoparticles (NPs) of SnO_2 using low energy excitations of 2.54 eV (488 nm) and 2.42 eV (514.5 nm). This…
Infrared-triggered photon upconversion in porous materials presents intriguing prospects for combined functionalities such as molecular sponge, energy harvesting and conversion functionalities. Metal-organic frameworks (MOFs) are one of the…
D$_2$ molecules, excited by linearly cross-polarized femtosecond extreme ultraviolet (XUV) and near-infrared (NIR) light pulses, reveal highly structured D$^+$ ion fragment momenta and angular distributions that originate from two different…