A pulse generator circuit for delivering a short high current pulse to a load (R L) comprising: a diode configured to store charges in its depletion layer when there is a forward flow of a current and to rapidly switch open after the depletion layer is substantially discharged by a reverse flow of a current; a switch configured to allow storage of energy from a source (V in) when it is opened and to allow the forward current flow after it is closed; a first resonant circuit configured to store energy from the source (V in) when the switch is opened and to provide the forward current flow through the diode after the switch is closed, thereby charging the depletion layer of the diode; and a second resonant circuit configured to store the energy transferred from the first resonant circuit after the switch is closed and to provide the reverse current flow through the diode until the depletion layer of the diode is substantially discharged, thereby causing the diode to rapidly switch open, and thereafter to provide a reverse current to the load (R L), wherein the first resonant circuit comprises a first capacitor (C 1) connected in series to a first inductor (L 1), wherein the first resonant circuit is connected in series to a resistor (R ch), the resistor (R ch) connecting the first capacitor (C 1) to the source (V in), wherein the second resonant circuit comprises a second capacitor (C 2) connected in series to a second inductor (L 2), the second inductor (L 2) connecting the second capacitor (C 2) in series to a parallel connection of the diode and the load (R L), wherein the switch is connected in parallel to the first resonant circuit, and wherein the second resonant circuit and the parallel connection are connected in parallel to the first inductor (L 1) so that the second capacitor (C 2) is connected to a connection point between the first capacitor (C 1) and the first inductor (L 1). a diode configured to store charges in its depletion layer when there is a forward flow of a current and to rapidly switch open after the depletion layer is substantially discharged by a reverse flow of a current; a switch configured to allow storage of energy from a source (V in) when it is opened and to allow the forward current flow after it is closed; a first resonant circuit configured to store energy from the source (V in) when the switch is opened and to provide the forward current flow through the diode after the switch is closed, thereby charging the depletion layer of the diode; and a second resonant circuit configured to store the energy transferred from the first resonant circuit after the switch is closed and to provide the reverse current flow through the diode until the depletion layer of the diode is substantially discharged, thereby causing the diode to rapidly switch open, and thereafter to provide a reverse current to the load (R L), wherein the first resonant circuit comprises a first capacitor (C 1) connected in series to a first inductor (L 1), wherein the first resonant circuit is connected in series to a resistor (R ch), the resistor (R ch) connecting the first capacitor (C 1) to the source (V in), wherein the second resonant circuit comprises a second capacitor (C 2) connected in series to a second inductor (L 2), the second inductor (L 2) connecting the second capacitor (C 2) in series to a parallel connection of the diode and the load (R L), wherein the switch is connected in parallel to the first resonant circuit, and wherein the second resonant circuit and the parallel connection are connected in parallel to the first inductor (L 1) so that the second capacitor (C 2) is connected to a connection point between the first capacitor (C 1) and the first inductor (L 1).