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Updated: Jun 16, 2026
12:03
A Method for Tracking the Time Evolution of Steady-State Evoked Potentials
Published on: May 25, 2019
Quasi-stationary population inversion on Kalpha transitions.
Applied Optics
|February 16, 2010
Summary
This study explores a K-alpha innershell scheme for quasi-continuous wave X-ray lasers. Achieving lasing requires overcoming photoionization losses, suggesting selective photoionization pumping and a heavy-ion plasma source.
Area of Science:
- Atomic Physics
- X-ray Laser Technology
- Plasma Physics
Background:
- Developing quasi-continuous wave (quasi-cw) X-ray lasers is a significant challenge.
- Existing K-alpha innershell schemes face limitations due to competing decay processes and photoionization losses.
Purpose of the Study:
- To evaluate the feasibility of a specific K-alpha innershell scheme for quasi-cw X-ray laser operation.
- To determine the conditions necessary for population inversion and gain in this scheme.
- To identify optimal pumping mechanisms and potential plasma sources.
Main Methods:
- Analysis of recently calculated atomic transition rates.
- Estimation of pumping requirements to overcome photoionization losses.
- Calculation of gain conditions for specific elements (silicon, calcium, copper).
Main Results:
- The K-alpha innershell scheme is only marginally feasible without specific mitigation strategies.
- Depletion of resonant absorbers via line shifts from multiple ionization is crucial.
- Photoionization pumping within a selective energy band is necessary, approaching blackbody emission levels.
Conclusions:
- The proposed K-alpha scheme requires precise control over ionization and absorption processes.
- Effective X-ray laser operation necessitates overcoming significant photoionization losses.
- A multiline heavy-ion plasma source is proposed as a viable pumping mechanism.
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