The influence of beam intensity on laser ablation quality and ablation size is experimentally studied on graphene-coated silicon/silicon dioxide substrates. With an amplified femtosecond-pulsed laser system, by systematically decreasing the average power, periodic stripes with decreasing widths are ablated. Histogram analyses of the untouched and ablated regions of scanning electron microscope ...

Evolving research has demonstrated that surgical cytoreduction of a high-grade glial neoplasm is an important factor in improving the prognosis of these difficult tumors. Recent advances in intraoperative imaging have spurred the use of stereotactic laser ablation (laser interstitial thermal therapy [LITT]) for intracranial lesions. Among other targets, laser ablation has been used in the focal...

We report on a novel nonlinear optical phenomenon, coined as ciliary white light, during laser ablation of transparent dielectrics. It is observed in 14 different transparent materials including glasses, crystals, and polymers. This phenomenon is also universal with respect to laser polarization, pulse duration, and focusing geometry. We interpret its formation in terms of the nonlinear diffrac...

Nickel ferrite nanoparticles are synthesized by pulsed laser ablation of corresponding bulk target in the double distilled water. Focused output of fundamental and third harmonics from pulsed Nd:YAG laser operating at 40 and 25 mJ/pulse energy respectively was allowed to irradiate the target. Produced colloidal solution was red in color and stable for several days. XRD, FTIR, VSM techniques are...

OBJECTIVE To assess outcomes in managing primary lentigo maligna through surgical excision, radiation therapy, and carbon dioxide laser ablation. METHODS Retrospective case series review of all patients with primary lentigo maligna diagnosed and treated in London, Ontario, Canada, between July 2, 1991, and June 29, 2010. RESULTS Seventy-five patients aged 39 to 93 years (mean age, 64.8 year...

Recurrent malignant glioma continues to be a clinical challenge, and repeat surgery is an option in only select patients. Stereotactic laser ablation, a new minimally invasive technique, can be used as an alternative to surgery. We review the current literature on laser ablation for recurrent malignant gliomas as well as discuss practical and theoretical advantages and disadvantages of this eme...

PURPOSE To determine the human corneal threshold ablation energy density for the 193-nm ArF excimer laser, approximating clinical conditions. METHODS The VISX Star (Santa Clara, CA) 193-nm argon fluoride excimer laser was used to ablate the cornea in human eye bank eyes under clinical conditions. Corneas were exposed to energy densities of 10, 20, 30, 35, 40, 45, and 140 to 160 mJ/cm2. Cornea...

Using automated laser pulse temporal shaping we report on enhancing spectral emission characteristics of ablation plasmas produced by laser irradiation of brass on ultrafast time scales. For different input irradiance levels, control of both atomic and ionic species becomes possible concerning the yield and the excitation state. The improved energy coupling determined by tailored pulses induces...

A negative isotropic magnetoresistance effect more than three orders of magnitude larger than the typical giant magnetoresistance of some superlattice films has been observed in thin oxide films of perovskite-like La(0.67)Ca(0.33)MnOx. Epitaxial films that are grown on LaAIO(3) substrates by laser ablation and suitably heat treated exhibit magnetoresistance values as high as 127,000 percent nea...

A clinical study was conducted to evaluate the efficacy and safety of percutaneous coronary excimer laser angioplasty in 60 patients with coronary artery disease. Forty-nine patients had stable exertional angina, and 11 patients had unstable angina despite medical therapy. A novel 1.4-mm diameter catheter with 20 quartz fibers of 100-microns diameter each arranged concentrically around a centra...