Chirped Bragg grating elements

Apparatus for producing high peak power ultra-short pulses, the apparatus comprising:

• a first volume Bragg grating element comprising a three-dimensional bulk of optical material having a first Bragg grating formed therein, said first Bragg grating defining a first Bragg grating vector and having a first grating period that varies as a function of position along the first Bragg grating vector;
• an optical amplifier;
• and
• a second volume Bragg grating element comprising a three-dimensional bulk of optical material having a second Bragg grating formed therein, said second Bragg grating defining a second Bragg grating vector and having a second grating period that varies as a function of position along the second Bragg grating vector;
• wherein the first volume Bragg grating element is adapted to receive an incident laser pulse, to stretch the incident laser pulse to form a stretched laser pulse, and to provide the stretched laser pulse to the optical amplifier,
• wherein the optical amplifier is adapted to receive the stretched laser pulse, to amplify the stretched laser pulse to form an amplified stretched pulse, and to provide the amplified stretched pulse to the second volume Bragg grating element, and
• wherein the second volume Bragg grating element is adapted to receive the amplified stretched pulse from the optical amplifier, and to compress the amplified stretched laser pulse to form a compressed amplified laser pulse.