High side driver IR2125
The second schematic (with load resistor) is better, as the load resistor is important for your high side driver to work.

During off state, the 100nF capacitor is charged, from current flowing through the diode and the load resistor.

As you turn on, the voltage at source rises, but so does the potential at the upper side of your capacitor and the high side driver is still able to further charge the gate capacitance until the FET is fully turn on.

If you want to use this circuit to create pulses you are fine, as on each pulse the 100nF capacitor will be recharged. You can't use  it to turn your FET on for a long time, as the 100nF capacitor will be finally drained (gate current leakage).