Theory of three-pulse photon echo spectroscopy with dual frequency combs

A theoretical analysis is carried out for the recently developed three-pulse photon echo spectroscopy employing dual frequency combs (DFC) as the light sources. In this method, the molecular sample interacts with three pulse trains derived from the DFC and the generated third-order signal is displayed as a two-dimensional (2D) spectrum that depends on the waiting time introduced by employing asynchronous optical sampling method. Through the analysis of the heterodyne-detected signal interferogram using a local oscillator derived from one of the optical frequency combs, we show that the 2D spectrum closely matches the spectrum expected from a conventional approach with four pulses derived from a single femtosecond laser pulse and the waiting time between the second and third field-matter interactions is given by the down-converted detection time of the interferogram. The theoretical result is applied to a two-level model system with solvation effect described by solvatochromic spectral density. The model 2D spectrum reproduces spectral features such as the loss of frequency correlation, dephasing, and spectral shift as a function of the population time. We anticipate that the present theory will be the general framework for quantitative descriptions of DFC-based nonlinear optical spectroscopy.Comment: 20 pages, 2 figures are included in the PDF fil

Evaluating Applicability of E-Service Quality in Online Hotel Bookings

This study evaluates applicability of E-service quality measurements in the context of online hotel bookings. Data was collected from an online survey of undergraduate college students at two universities in the United States. The Transaction Process-based Framework (eTransQual) conceptualized by Bauer et al. (2006) was adapted, and the dimensionality of e-service quality was identified. The study identified process/reliability as the most important factor influencing overall quality of booking websites