相关论文: Transient nuclear inversion by X-Ray Free Electron…
When a high-contrast ultra-relativistic laser beam enters a micro-sized plasma waveguide, the pulse energy is coupled into waveguide modes, which remarkably modifies the interaction of electrons and electromagnetic wave. The electrons that…
Biomedical applications requiring tissue diagnosis, activation, and treatment could be substantially leveraged by optical methods, owing to their unique feature set. However, their widespread application is severely limited by the strong…
The electromagnetic transition of two-level atomic systems in a waveguide is calculated. Compared with the result in free space, the spontaneous emission rate decrease because the phase space is smaller, and meanwhile, some resonance…
We enhanced the total transmission of light through a disordered waveguide with spatially inhomogeneous scattering and loss by shaping the incident wavefront of a laser beam. Using an on-chip tapered lead, we were able to access all input…
Owing to the rapid progress in laser technology, very high-contrast femtosecond laser pulses of relativistic intensities become available. These pulses allow for interaction with micro-structured solid-density plasma without destroying the…
Transient X-ray absorption techniques can measure ultrafast dynamics of the elemental edges in a material or multiple layer junction, giving them immense potential for deconvoluting concurrent processes. However, the interpretation of the…
Light can be confined transversely and delivered axially in a waveguide. However, waveguides are lossy static structures whose modal characteristics are fundamentally determined by the boundary conditions, and thus cannot be readily changed…
Coherent population transfer between nuclear states using x-ray laser pulses is studied. The laser pulses drive two nuclear transitions between three nuclear states in a setup reminding of stimulated Raman adiabatic passage used for atomic…
The transition from the amplification of spontaneous emission to superfluorescence in a three-level and swept-gain medium excited by an X-ray free electron laser pulse is theoretically investigated. Given the specific time scale of X-ray…
Waveguides offer a means to controllably couple atomic ensembles to the electromagnetic field therein. Here, we demonstrate x-ray propagation in planar thin-film waveguides coupled to M\"ossbauer nuclei under collective resonant excitation…
Experimental evidence of mode-selective evanescent power coupling at telecommunication frequencies with efficiencies up to 75 % from a tapered optical fiber to a carefully designed metal nanoparticle plasmon waveguide is presented. The…
We investigate the effect of a laser shining perpendicularly to a waveguide channeling two-level atoms. For weak transversal coupling the excitation of transverse atomic levels occurs at avoided crossings associated with "Rabi resonances"…
The trapping of ultracold atoms using two-colour evanescent light waves formed by propagating modes of suspended optical rib waveguides is modelled in different configurations. Reducing the anisotropy of the two-colour evanescent optical…
Understanding how evanescent modes mediate energy transfer in tapered elastic waveguides is of paramount interest, as it unlocks new strategies for wave control and manipulation. Evanescent modes play a crucial role in energy localization…
We design compact waveguide couplers via impedance-tunable transformation optics. By tuning impedance coefficients in the original space, two-dimensional metallic and dielectric waveguide couplers are designed with a high efficiency.…
The goal to control short-wavelength radiation for the investigation and manipulation of ultrafast dynamics in quantum systems coevolves with the growing availability of extreme-ultraviolet (XUV) and x-ray sources from high-harmonic…
We study the effect of laser driving on a minimal model for a hexagonal two-dimensional material with broken inversion symmetry. Through the application of circularly polarised light and coupling to a thermal free electron bath, the system…
The X-ray free-electron laser oscillator (XFELO) has recently been reconsidered a promising candidate for producing high-brightness, fully coherent pulses in the hard X-ray regime. This letter proposes a gain-guided XFELO scheme, avoiding…
Using metal-clad (or plasmonic) waveguide structures in semiconductor lasers carries a promise of reduced size, threshold, and power consumption. This promise is put to a rigorous theoretical test, that takes into account increased…
We investigate the subwavelength imaging capacity of a two-dimensional fanned-out plasmonic waveguide array, formed by air channels surrounded by gold metal layers for operation at near-infrared wavelengths, via finite element simulations.…