Light source system and method of operation

A method of light generation, comprising:

• at an electron bunch splitter comprising a set of one or more kicker cavities, throughout a time interval, operating the set of kicker cavities according to a timing scheme, comprising, for each kicker cavity of the set, generating a respective temporally-periodic electromagnetic (EM) field within the kicker cavity;
• at a pulsed light source of a photocathode system, throughout the time interval, generating a pulse train comprising a sequence of light pulses, the pulse train defining a seed repetition rate;
• at the photocathode system, during a first sub-interval of the time interval, generating a first plurality of spatially-separated electron bunches defining a bunch repetition rate less than the seed repetition rate, the first plurality defining a first substantially-periodic pattern, wherein generating the first plurality of spatially-separated electron bunches comprises:
• at a pulse picker of the photocathode system:
• receiving a first contiguous segment of the pulse train;
• transmitting a first subset of light pulses of the first contiguous segment to a photocathode of the photocathode system, the first subset defining the bunch repetition rate;
• and
• not transmitting a second subset of light pulses of the first contiguous segment to the photocathode, wherein the first and second subsets partition the first contiguous segment;
• at the photocathode:
• receiving the first subset of light pulses;
• and
• in response to receiving the first subset of light pulses, generating the first plurality of spatially-separated electron bunches, comprising, for each light pulse of the first subset:
• in response to receiving the light pulse, generating a respective electron bunch of the first plurality of spatially-separated electron bunches;
• during the first sub-interval, at the electron bunch splitter, receiving each electron bunch of the first plurality of spatially-separated electron bunches from the photocathode, wherein, based on the timing scheme, the electron bunch splitter:
• directs a first subset of electron bunches of the first plurality onto a first trajectory into a first undulator, the first subset defining a first undulator repetition rate;
• and
• directs a second subset of electron bunches of the first plurality onto a second trajectory into a second undulator separate from the first undulator, the second subset defining a second undulator repetition rate;
• at the photocathode system, during a second sub-interval of the time interval, wherein the second sub-interval does not overlap the first sub-interval, generating a second plurality of spatially-separated electron bunches defining a second bunch repetition rate substantially equal to the bunch repetition rate, the second plurality defining a second substantially-periodic pattern substantially different from the first substantially-periodic pattern, wherein generating the second plurality of spatially-separated electron bunches comprises:
• at a pulse picker of the photocathode system:
• receiving a second contiguous segment of the pulse train;
• transmitting a third subset of light pulses of the second contiguous segment to the photocathode, the third subset defining the second bunch repetition rate;
• and
• not transmitting a fourth subset of light pulses of the second contiguous segment to the photocathode, wherein the third and fourth subsets partition the second contiguous segment;
• at the photocathode:
• receiving the third subset of light pulses;
• and
• in response to receiving the third subset of light pulses, generating the second plurality of spatially-separated electron bunches, comprising, for each light pulse of the third subset:
• in response to receiving the light pulse, generating a respective electron bunch of the second plurality of spatially-separated electron bunches;
• during the second sub-interval, at the electron bunch splitter, receiving each electron bunch of the second plurality of spatially-separated electron bunches from the photocathode, wherein, based on the timing scheme, the electron bunch splitter:
• directs a third subset of electron bunches of the second plurality onto the first trajectory, the third subset defining a third subset repetition rate substantially equal to the first undulator repetition rate;
• and
• directs a fourth subset of electron bunches of the second plurality onto a third trajectory, wherein the fourth subset of electron bunches are not directed into the first undulator and are not directed into the second undulator;
• at the first undulator:
• during the first sub-interval, receiving the first subset of electron bunches such that each electron bunch of the first subset traverses a first gap of the first undulator, thereby generating a respective optical output via free-electron lasing;
• and
• during the second sub-interval, receiving the third subset of electron bunches such that each electron bunch of the third subset traverses the first gap, thereby generating a respective optical output via free-electron lasing;
• and
• at the second undulator, during the first sub-interval, receiving the second subset of electron bunches such that each electron bunch of the second subset traverses a second gap of the second undulator, thereby generating a respective optical output via free-electron lasing.