Resonance-Enhanced Photon Excitation Spectroscopy of the Even-Parity 3p^5（2P1/2）nl′ [K′]J （l′=1, 3） Autoionizing Rydberg States of Ar

Metastable 40Ar＊ atoms are produced in the two metastable states 3p54s [3/2]2 and 3p5 4s′ [1/2]0 in a pulsed DC discharge in a beam, and are subsequently excited to the even-parity autoionizing resonance series 3pSnp′[3/2]1,2, 3p5 np′ [1/2]1, and 3p5nf′[5/2]3 using single photon excitation with a pulsed dye laser. The excitation spectra of the even-parity autoion- izing resonance series from the metastable 40Ar＊ are obtained by recording the autoionized Ar＋ ions with time-of-flight ion detection in the photon energy range of 32500-35600 cm-1 with an experimental bandwidth of 〈0.1 cm-1. A wealth of autoionizing resonances are newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects are derived.

Resonance-Enhanced Photon Excitation Spectroscopy of the Even-Parity Autoionizing Rydberg States of Xe

Xenon atoms were produced in their metastable states 5p^56s[3/2]2 and 5p^56s＇[1/2]0 in a pulsed DC discharge in a beam, and subsequently excited to the even-parity autoionizing Rydberg states 5p^5np＇ [3/2] 1,[1/2] 1, and 5p^5nf＇ [5/2] 3 using single photon excitation. The excitation spectra of the even-parity autoionizing resonance series from the metastable 129Xe were obtained by recording the autoionized Xe＋ with time-of-flight ion detection in the photon energy range of 28000-42000 cm-1. A wealth of autoionizing resonances were newly observed, from which more precise and systematic spectroscopic data of the level energies and quantum defects were derived.

Aptamerized silica/gold nanocapsules for stimulated release of doxorubicin through remote two-photon excitation

Precision-based drug delivery via remote triggering is fast becoming an attractive therapeutic design and is highly useful in complicated clinical situations that may require accurate site-delivery of drug while reducing the risk of collateral damage to surrounding healthy tissue.Of the many strategies available to achieve these desirable effects,silica/gold nano-assemblies offers a practical means to achieving these aims.Herein,as a proof-of-concept,a silica nanocapsule passivated with a gold outer nanoshell had been fabricated to deliver Doxorubicin,and this nano-assembly can be remotely triggered via two-photon excitation(TPE),even under in vivo setting.A polyethylene glycol(PEG)layer as well as AS1411 DNA aptamer had also been grafted to the surface to improve homing specificity toward MDA-MB-231 breast cancer tissue.The assembly of silica/gold nanocapsules was characterized via TEM,FTIR,and UVVis to validate the the nanoconstruct.Upon TPE irradiation,a higher expression level of Annexin V and Caspase-3 was observed in both in vitro and in vivo animal models.A significant reduction in tumor size on mice model was noticed after 21 days,and these results had suggested a viable nano-sized design serving as remotely triggered drug release platform based on current well-established silica nanoparticulate methodologies.

The Size of a Photon

This paper begins by exploring a useful and neglected detail of a photon—its physical size perpendicular to the direction of propagation in the same way as an atom or neutron has a physical size. Such a photon size would be quite separate from the cross-section of a photonic interaction, which depends on the material interacting. Such a perpendicular dimension of a photon will be invariant under Lorentz transform parallel to the light propagation direction and will thus be the same for all frequencies of light. This study also leads to new details about how a photon interacts, offering an explanation for the familiar physics where light slightly above and below the mean frequency of an excited state can still excite the same state without violation of conservation of energy—a mystery explored thoroughly in a previous paper without finding the solution offered here. As usual, a better elucidation of the details of light interaction also leads to new insights—especially about the vacuum field. The Appendix summarizes some previous research relevant to this

Two-mode excited entangled coherent states and their entanglement properties

This paper introduces two types of two-mode excited entangled coherent states （TMEECSs） ψ±（（α,m,n））, studies their entanglement characteristics, and investigates the influence of photon excitations on quantum entanglement. It shows that for the state （ψ＋ （α, m, m）} the two-mode photon excitations affect seriously entanglement character while the state [ ψ-（α, m, m）） is always a maximally entangled state, and shows how such states can be produced by using cavity quantum electrodynamics and quantum measurements. It finds that the entanglement amount of the TMEECSs is larger than that of the single-mode excited entangled coherent states with the same photon excitation number.

Remarkable fluorescence enhancement of upconversion composite film and its application on mercury sensing

To achieve a stable, sensitive, and high-efficiency biological probe, a novel NaYF4：Yb,Er nanocrystals/TiO2 inverse opal composite film was designed by self-assembly and solvent evaporation methods. 32-fold enhanced upconversion（UC） emission was investigated under 980 nm excitation. According to size-dependency, excitation power density-dependency as well as photonic stop band（PSB）-dependency upconversion spectra, the enhancement mechanism of the composite film was put down to the stochastical diffraction of IOPCs multi-layered structure to the excitation laser. On the basis of the enhancement effect of the composite film, energy transfer between upconversion nanoparticles（UCNPs） and quantum dots（QDs）, and the sensitive sensing of CdTe QDs on mercury, the UC composite film was used for sensing of Hg^2＋ in serum. The solid sensor as a mercury detector owns lots of superiorities such as feasible operation, good linear relationship（R=0.997）, low limit of detection（70.5 nmol/L） and thus may have broad prospects in the biosensing field.