Concepedia

Demonstration of x-ray amplifiers near the carbon<i>K</i>edge

B. J. MacGowan, S. Maxon, L. B. Da Silva, D. J. Fields, C. J. Keane, D. L. Matthews, A. L. Osterheld, J. H. Scofield, G. Shimkaveg, G. F. Stone

Physical Review Letters · 1990 · 130 citations · 18 references

DOI

TL;DR

This work reports the first demonstration of an x‑ray amplifier operating on the short‑wavelength side of the carbon K edge within the water window. The authors aim to show that the Ni‑like 4d‑4p laser scheme can be scaled to deliver coherent power suitable for holographic imaging and related applications. They achieved gains of 2.3 cm⁻¹ at 44.83 Å (Ta) and 2.6 cm⁻¹ at 43.18 Å (W) with 250‑ps pulses, extending the laser scheme to wavelengths near the carbon K edge and demonstrating performance relevant to live‑cell holography.

Abstract

The Ni-like 4d-4p laser scheme has been extended to wavelengths near the K absorption edge of carbon. A gain of 2.3 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ with a duration of 250 psec was observed in Ni-like Ta at 44.83 \AA{} (a wavelength close to optimal for holographic imaging of live cells). Ni-like W produced a gain of 2.6 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$ with a total of seven gainlengths of amplification at 43.18 \AA{}. This is the first demonstration of an x-ray amplifier on the short-wavelength side of the carbon K edge, within the ``water window.'' Both lasers should be scalable to coherent power sufficient for holographic imaging and other applications.