Calculation of effective pump dose in X-ray-pump/X-ray-probe experiments

Area of Science:

• Ultrafast X-ray Science
• Materials Science
• Computational Physics

Background:

• Pump-probe experiments using ultrafast X-rays deposit energy non-uniformly in solid samples.
• X-ray probe pulses measure volume-integrated averages from these non-uniform distributions.
• Simulations typically assume uniform irradiation, complicating accurate predictions.

Purpose of the Study:

• To develop a simplified method for simulating X-ray irradiated solids.
• To reduce the computational cost of predicting volume-integrated observables.
• To accurately model the effects of non-uniform energy deposition in pump-probe experiments.

Main Methods:

• Proposed a scheme to calculate an effective pump pulse fluence.
• Developed a method to approximate volume-integrated observables with a single calculation.
• Focused on simplifying simulations for X-ray irradiated solid materials.

Main Results:

• The proposed scheme yields an effective fluence.
• Calculations using the effective fluence closely match volume-integrated observables.
• Significantly reduces the computational effort compared to multiple simulations.

Conclusions:

• The effective fluence scheme simplifies computational simulations of X-ray irradiated solids.
• This method provides a computationally efficient way to predict volume-integrated observables.
• Enables more accessible and faster research in ultrafast X-ray science.