Gain saturation regime for laser-driven tabletop, transient Ni-like ion X-Ray lasers

Area of Science:

• Atomic physics
• Plasma physics
• Laser science

Background:

• Nickel-like ions are crucial for developing X-ray lasers.
• Achieving high gain and saturation is essential for practical X-ray laser applications.
• Tabletop chirped-pulse amplification lasers offer a compact platform for generating X-ray lasers.

Purpose of the Study:

• To demonstrate small signal gain saturation on transient-gain Ni-like ion X-ray lasers.
• To investigate the performance of these lasers at various wavelengths and energies.
• To optimize laser driver parameters for improved beam characteristics.

Main Methods:

• Utilized a high-power, chirped-pulse amplification, tabletop laser system.
• Employed a traveling-wave excitation scheme.
• Measured gain saturation, gain coefficients, and gL products for Ni-like ions.

Main Results:

• Achieved small signal gain saturation on several transient-gain Ni-like ion X-ray lasers.
• Observed strong amplification for Ni-like Sn at 119 Å and Ni-like Pd at 147 Å.
• Determined a gain of 62 cm⁻¹ and a gL product of 18 for Ni-like Pd at 147 Å.
• Optimized laser driver parameters resulting in beam divergence and deflection angles of 2-5 mrads.

Conclusions:

• Demonstrated the feasibility of achieving gain saturation in Ni-like ion X-ray lasers using a compact laser system.
• The results indicate significant potential for these X-ray lasers in various scientific applications.
• Optimized laser parameters are crucial for achieving high-quality X-ray laser beams.