相关论文: Determining Reaction Pathways at Low Temperatures …

Temperature dependence of the thermal rate constants and kinetic isotope effects (KIE) of the CN + C2H6 gas-phase hydrogen abstraction reaction was theoretically determined within the 25-1000 K temperature range, i.e., from ultra-low to…

We analyze reactive collisions of a single Ba$^+$ ion in contact with an ultracold gas of Rb atoms at low three-body collision energies of 2.2(9) mK$\times k_{\mathrm{B}}$. Mapping out the Ba$^+$ loss rate dependence on the Rb atom density…

Great advances in precision quantum measurement have been achieved with trapped ions and atomic gases at the lowest possible temperatures. These successes have inspired ideas to merge the two systems. In this way one can study the unique…

We present a combined experimental and theoretical study focussing on the quantum tunneling of atoms in the reaction between CH4 and OH. The importance of this reaction pathway is derived by investigating isotope substituted analogs.…

Rate constants for the N + C2 reaction have been measured in a continuous supersonic flow reactor over the range 57 K to 296 K by the relative rate technique employing the N + OH - H + NO reaction as a reference. Excess concentrations of…

The enhancement of a cryogenic radio frequency 22 pole trap instrument by the addition of ring electrodes is presented in detail. The ring electrodes tightly surround the poles and only a fraction of the applied electric potential…

The system that describes the dynamics of a Bose-Einstein Condensate (BEC) and the thermal cloud at finite temperature consists of a nonlinear Schrodinger (NLS) and a quantum Boltzmann (QB) equations. In such a system of trapped Bose gases…

We study cooling of the collective vibrational motion of two 138Ba+ ions confined in an electrodynamic trap and irradiated with laser light close to the resonances S_1/2-P_1/2 (493 nm) and P_1/2-D_3/2 (650 nm). The motional state of the…

Here we report the results of an experimental and theoretical study of the gas-phase reactions between O($^1$D) and H$_2$O and O($^1$D) and D$_2$O at room temperature and below. On the experimental side, the kinetics of these reactions have…

Ground state cooling and coherent manipulation of ions in an rf-(Paul) trap is the prerequisite for quantum information experiments with trapped ions. With resolved sideband cooling on the optical S1/2 - D5/2 quadrupole transition we have…

We perform numerical simulations of trapped $^{171}$Yb$^+$ ions that are buffer gas cooled by a cold cloud of $^6$Li atoms. This species combination has been suggested to be the most promising for reaching the quantum regime of interacting…

Cooling of particles to mK-temperatures is essential for a variety of experiments with trapped charged particles. However, many species of interest lack suitable electronic transitions for direct laser cooling. We study theoretically the…

Deuterium enhancement of monodeuterated species has been recognized for more than 30 years as a result of the chemical fractionation that results from the difference in zero point energies of deuterated and hydrogenated molecules. The key…

The experimental determination of the reaction rate coefficients for production and destruction of $\text{HCN}^+$ and $\text{HNC}^+$ in collisions with $\text{H}_2$ is presented. A variable temperature 22 pole radio frequency ion trap was…

This study reports the results of an experimental and theoretical investigation of the N(2D) + H2 and N(2D) + D2 reactions at room temperature and below. On the experimental side, a supersonic flow (Laval nozzle) reactor was employed to…

We present a room-temperature Extreme High Vacuum (XHV) system engineered to support the long-duration operation of a trapped-ion quantum processor. Background-gas collisions impose limitations on trapped-ion performance and scalability by…

We report on a cycling scheme for Doppler cooling of trapped OH$^+$ ions using transitions between the electronic ground state $X^3\Sigma^-$ and the first excited triplet state $A^3\Pi$. We have identified relevant transitions for photon…

CO2 is one of the dominant components of the interstellar ice. Recent observations show CO2 exists more abundantly in polar (H2O-dominated) ice than in apolar (H2O-poor) ice. CO2 ice formation is primarily attributed to the reaction between…

The ionization mechanism of the low-ionization gas in quiescent red sequence galaxies has been a long-standing puzzle. Direct temperature measurements would put strong constraints on this issue. We carefully selected a sample of quiescent…

We have measured the reaction rates of trapped, buffer gas cooled Th$^{3+}$ and various gases and have analyzed the reaction products using trapped ion mass spectrometry techniques. Ion trap lifetimes are usually limited by reactions with…