Accurate rotation-vibration energy levels and transition dipoles of the molecule thiophosgene are used to model the execution of quantum gates with shaped laser pulses. Qubits are encoded in 2 n vibrational computing states on the ground electronic surface of the molecule. Computations are carried out by cycling amplitude between these computing states and a gateway state with a shaped laser pulse. The shaped pulse that performs the computation is represented by a physical model of a 128-1024 channel pulse shaper. Pulse shapes are optimized with a standard genetic algorithm, yielding experimentally realizable computing pulses. The robustness of optimization is studied as a function of the vibrational states selected, rotational level structure, additional vibrational levels not assigned to the computation, and compensation for laser power variation across a molecular ensemble.

Small anions in polar solvents are benchmark systems for fast vibrational energy relaxation (VER) due to the Coulombic effects that promote solute-solvent interactions. In order to investigate the effects of solute charge and solvent isotope effects on vibrational spectra and dynamics, infrared pump-probe studies have been used to determine VER (T(1)) times for the pseudohalide acids, XNCS and XN(3) (X = H, D), in protic solvents, H(2)O, D(2)O, CH(3)OH, and CD(3)OD. These results are compared with the well-studied azide and thiocyanate anions. Solvent isotope effects of the vibrational frequency shifts of azide and for VER rates of both azide and thiocyanate are similar to those for the hydro- and deutero-protonated species in water. VER times are longer for HN(3)/H(2)O, HN(3)/CH(3)OH, and DN(3)/CD(3)OD (T(1) = 2.3, 5.6, and 3.7 ps, respectively) than for the corresponding anions in solution (0.8, 3.0, and 2.1 ps), which is consistent with the idea that ions relax more quickly than neutrals. But the times measured for DN(3)/D(2)O, HNCS/H(2)O, and DNCS/D(2)O (T(1) = 1.2, 1.5, and 4.4 ps, respectively) are shorter than for the corresponding ions (2.3, 2.7, and 22.0 ps). Fast VER for DN(3) in D(2)O is attributed to strong coupling to nearby solvent bands and/or to Fermi resonances that promote intramolecular vibrational relaxation. For the HNCS and DNCS, the faster rates can be understood by recognizing that the charge displacements are similar to those for the anion.

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Solution-deposited nanoscale films of RuO2 (“nanoskins”) are effective transparent conductors once calcined to 200 °C. Upon heating the nanoskins to higher temperature the nanoskins show increased transmission at 550 nm. Electronic microscopy and X-ray diffraction show that the changes in the optical spectrum are accompanied by the formation of rutile RuO2 nanoparticles. The mechanism for the spectral evolution is clearly observed with ultrafast optical measurements. Following excitation at 400 nm, nanoskins calcined at higher temperatures show increased transmission above 650 nm, consistent with the photobleaching of a surface-plasmon resonance (SPR) band. Calculations based on the optical constants of RuO2 substantiate the presence of SPR absorption. Sheet resistance and transient terahertz photoconductivity measurements establish that the nanoskins electrically de-wire into separated particles. The plasmonic behavior of the nanoskins has implications their use in a range of optical and electrochemical applications.

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