Related papers: Optical Stark Effect of a Single Defect on TiO2(11…
By the use of a point charge model based on the Judd-Ofelt transition theory, the luminescence from Eu3+ ions embedded in Gd2O3 clusters is calculated and compared to the experimental data. The main result of the numerical study is that…
Resonant optical excitation of apical oxygen vibrational modes in the normal state of underdoped YBa2Cu3O6+x induces a transient state with optical properties similar to those of the equilibrium superconducting state. Amongst these, a…
Using a single trapped barium ion we have developed an rf spectroscopy technique to measure the ratio of the off-resonant vector ac Stark effect (or light shift) in the 6S_{1/2} and 5D_{3/2} states to 0.1% precision. We find R = Delta_S /…
We study the energy spectrum of atoms trapped in a vertical 1D optical lattice in close proximity to a reflective surface. We propose an effective model to describe the interaction between the atoms and the surface at any distance. Our…
By tightly focussing a laser field onto a single cold ion trapped in front of a far-distant dielectric mirror, we could observe a quantum electrodynamic effect whereby the ion behaves as the optical mirror of a Fabry-P\'erot cavity. We show…
A detailed reexamination of the (110) surface structure of rutile TiO2 has been carried out using first-principles total-energy methods. This investigation is in response to a recent high-precision LEED-IV measurement revealing certain…
Integrating nanoscale opto-electronic functions is vital for applications such as optical emitters, detectors, and quantum information. Lanthanide atoms show great potential in this endeavor due to their intrinsic transitions. Here, we…
We study the tunneling of a two-level atom in a double well potential while the atom is coupled to a single electromagnetic field mode of a cavity. The coupling between internal and external degrees of freedom, due to the mechanical effect…
The wave-like nature of electrons is evident from quantum interference effects observed during the photoemission process. When there are different nuclei in the unit cell of a crystal and/or structural distortions, photo-electron…
Effect of uncompensated Ga-V co-doping on structural phase transition, grain growth process and optical properties of TiO2 is reported here. Inhibition of phase transition due to co-doping is confirmed by X-ray diffraction measurement.…
We have studied the Tamm-type surface state of La(0001) by tunneling spectroscopy within a wide range of tunneling currents from 0.1 nA to 8000 nA, thereby tuning the electric-field strength in a tip-vacuum-sample tunnel junction. We…
We report on electron momentum distributions from single ionization of Ar in strong orthogonally polarized two-color (OTC) laser fields measured with the COLTRIMS technique. We study the effect of Coulomb focusing whose signature is a cusp…
In this paper we present some concepts in heavy ion atomic physics for the extraction of parity violating effects. We investigate the effects of the so-called Stark-quenching, i.e., the fast decay of a meta stable state induced by a Stark…
Observing changes in molecular structure requires atomic-scale {\AA}ngstrom and femtosecond spatio-temporal resolution. We use the Fourier transform (FT) variant of laser-induced electron diffraction (LIED), FT-LIED, to directly retrieve…
A higher--twist nuclear enhancement of $R = \sigma_L/\sigma_T$, as might be expected to arise due to fermi motion and whose magnitude is within the error-bars of recent experiment, is shown to lead to a monotonic {\it decrease} in the ratio…
Charge transfer between metal nanoparticles and the supported TiO2 surface is primarily important for catalytic applications as it greatly affects the catalytic activity and the thermal stability of the deposited nanoparticles on the…
We study Bragg scattering at 1D optical lattices. Cold atoms are confined by the optical dipole force at the antinodes of a standing wave generated inside a laser-driven high-finesse cavity. The atoms arrange themselves into a chain of…
We present an analytical derivation of the on-axis performance of Adaptive Optics systems using a given number of guide stars of arbitrary altitude, distributed at arbitrary angular positions in the sky. The expressions of the residual…
Raman laser pulses are used to induce coherent tunnelling between neighbouring sites of a vertical 1D optical lattice. Such tunneling occurs when the detuning of a probe laser from the atomic transition frequency matches multiples of the…
Monolayers of transition-metal dichalcogenides have shown that uniaxial strain changes both the photoluminescence emission energy and intensity. The changes are attributed to the band-structure evolution under tensile strain where both the…