Shrinking the device dimension has long been the pursuit of the semiconductor industry to increase the device density and operation speed. In the application of thin film transistors (TFTs), all-organic TFT arrays made by all-solution process are desired for low cost and flexible electronics. One of the greatest challenges is how to achieve ultrashort channel through a cost-effective method. In...

Traditionally nanosecond laser pulses have been used for Laser-induced Breakdown Spectroscopy (LIBS) for quantitative and qualitative analysis of the samples. Laser produced plasmas using nanosecond laser pulses have been studied extensively since 1960s. With the advent of short and ultrashort laser pulses, there has been a growing interest in the applications of femtosecond and picosecond lase...

High order harmonic generation (HHG) from laser solid-density plasma interactions is considered as a promising way to generate bright and ultrashort burst of x-rays. One of the key issues for HHG is the low conversion efficiency due to a power law fall off in harmonic intensity. Here, we explore a possible mechanism for HHG enhancement by reflecting an intense laser pulse multiple times between...

Intense laser fields, comparable in magnitude with the Coulomb field within atoms and molecules, can be generated by focussing high-energy and ultrashort laser pulses. When exposed to such a strongly perturbing field, molecules exhibit various exotic features that cannot be observed in weak laser fields. We are seeking a deeper understanding of the behavior of molecules in intense laser fields,...

We review the problem of measuring an ultrashort laser pulse and then describe several experimentally simple, accurate, and very reliable methods for measuring both very simple laser pulses and very complex ultrashort light pulses. Each of these methods comprises only a few easily aligned components, and they allow the measurement of a wide range of pulses, including those with time-bandwidth p...

In ultrashort pulse ͑Ͻ10 ps͒ laser ablation of dielectrics, affected materials are first transformed into absorbing plasma with metallic properties and, then, the subsequent laser-plasma interaction causes material removals. For ultrashort-pulse laser ablation of dielectrics, this study proposes a model using the Fokker-Planck equation for electron density distribution, a plasma model for the opt...

Frequency-resolved optical gating (FROG) is a technique that produces a spectrogram of an ultrashort laser pulse optically. While a great deal of information about the pulse can be gleaned from its FROG trace, often it is desirable to obtain all of the pulse information immediately, in real time. Quantitative information about the pulse is not readily obtainable from its spectrogram without the...

We have investigated the nonlinear susceptibility of atoms induced by high intensity, ultrashort laser pulses using a numerical solution of the timedependent Schrödinger equation. We found that the instantaneous nonlinear susceptibility becomes saturated at high intensity. We also found that the saturation is closely linked to depletion of the ground state. Based on the numerical results, a sim...