Formation of a strong quasi-static electric field when irradiated by intense laser pulses of a target with a spherical microcavity

The collapse of a spherical microcavity in the plasma target under symmetrical irradiation of the target by intense laser pulses is numerically studied. Configurations with 2, 4, and 8 laser pulses are considered. The formation of the quasi-static strong electric field in the center of the cavity as a result of collapse is demonstrated. It is shown that the 8-pulse configuration is the most optimal one from the point of view of increasing the ion concentration in the central bunch and increasing the electric field amplitude, while the transition from the 2-pulse to the 8-pulse configuration leads to the 1.5-fold increase in the field amplitude while maintaining the total laser pulse energy. The estimates show that for the parameters of the XCELS facility in the 8-pulse configuration one can expect the maximum electric field amplitude of 1.61×10¹⁴ V/cm, or 1.2% of the Schwinger field.