Superconducting transition edge bolometers on micromachined silicon membranes have been fabricated. The optical response is 580 V/W at a time constant of 0.4 ms. The detectivity D* is 3.8×109 (cm Hz1/2 W−1) at a temperature of 84.5 K and within the frequency regime 100<f<300 Hz. This is one of the fastest composite type bolometers ever reported. Upon thermal optimization, this type of detector should be competitive with state-of-the-art quantum detectors.
One-photon ionization by a pulsed VUV laser has been employed to probe infrared multiphoton excitation and dissociation (IR-MPE/D) dynamics in real time, in situ, and collision free during excitation by a CO2− laser pulse. In this first experiment acetic anhydride has been used as the parent molecule to demonstrate the feasibility and to study properties of the method. Using the 118.4 nm radiation from a VUV laser as source for photoionization, ions have been observed mass selectively with time resolution in the nanosecond range, determined by the laser pulse duration. By following production and decay rates of ions, the time dependence of the excitation and decay of parent molecules, and the evolution of neutral intermediates in primary and sequential steps could be observed, from which detailed information on excitation and dissociation pathways was deduced.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.