Darrell S. DiCicco

Contact microscopy with a soft X‐ray laser

A soft X‐ray laser of output energy 1–3 mJ at 18–2 nm was used to record high resolution images of biological specimens. The contact images were recorded on photoresist which was later viewed in a scanning electron microscope. A composite optical X‐ray laser microscope ‘COXRALM’ of novel design is also described.

Soft X-Ray Laser Microscopy

Microscopes based on soft X-ray lasers possess unique advantages in bridging the gap between high resolution electron microscopy of dehydrated, stained cells and light microscopy at comparatively low resolution of unaltered live cells. The high brightness and short pulse duration of soft X-ray lasers make them ideal for flash imaging of live specimens.

Toward small-scale x-ray lasers (Invited Paper)

An overview of the X-ray Laser project at Princeton University will be given. Emphasis will be on improvements being made to the small scale soft x-ray laser (SXL). New target designs to enhance cooling and others to reduce losses due to beam refraction have been introduced though results are stilt preliminary. Proof of principle experiments for the application of the SXL to both transmission and reflection microscopy have been performed. To generate shorter wavelength x-ray lasers on a reasonable scale-size, a high power, 300 fsec pulse duration, ultraviolet KrF laser system (the PSP-laser) has been developed. Of the several theoretical schemes which exist, the two-laser approach and a newly proposed recombination approach will be described. The new approach proposes to scale the existing 18.2 nm recombination x-ray laser to shorter wavelength (<4 nm) by making use of the short-pulse pump laser and rapid cooling associated with the adiabatic expansion of µsphere targets.

X-Ray Laser Microscopy

This paper describes work at Princeton on X-ray laser microscopy. Related to this work is a new system for the development of an X-ray laser in the wavelength region from 5 nm to 1 nm utilizing a Powerful Sub-Picosecond Laser (PP-Laser) of expected peak power up to 0.5 TW in a 300 fs pulse. Soft X-ray spectra generated by the interaction of the PP-Laser beam with different targets are presented and compared to the spectra generated by a much less intense laser beam (20-30 GW). The development of additional amplifiers for the recombining soft X-ray laser and the design of a cavity are presented from the point of view of applications for X-ray microscopy and microlithography.