Design Considerations for Dispersion Control with a Compact Bonded Grism Stretcher for Broadband Pulse Amplification

We report on the design of a compact grism-pair stretcher for a near-infrared noncollinear optical parametric chirped-pulse amplification (OPCPA) system. The grisms are produced by bonding a grating to a prism using a resin. The stretcher is capable of controlling a bandwidth of over 300？nm, which is suitable for parametric amplification of few-cycle pulses. After amplification, pulses can be compressed by the dispersion of optical glass, and the residual group-delay can be compensated with an acousto-optic programmable dispersive filter (AOPDF). 1. Introduction Energetic few-cycle pulses enable many new applications in attosecond science, quantum coherent control, and nonlinear optics [1]. Single attosecond XUV pulses can be produced via high harmonic generation (HHG) driven by few-cycle pulses, enabling attosecond spectroscopic applications and the control of atomic-scale electron motion [2]. Techniques for generating few-cycle pulses, such as, the use of a carefully dispersion managed Kerr-lens mode-locked Ti:sapphire oscillator [3], self-phase modulation in a single-mode fiber [4], and in a gas-filled capillary [5] have been proposed and demonstrated. However, it has been difficult to increase the energy of the few-cycle pulses beyond the few-mJ level [6]. Presently, noncollinear optical parametric chirped-pulse amplification (OPCPA) is a promising route for synthesis of more energetic few-cycle waveforms [7, 8]. Similar to classical chirped-pulse-amplification (CPA) [9], generating ultrashort pulses with an OPCPA system involves stretching, amplifying, and subsequently compressing a pulse to its transform limit and requires precise dispersion management [8]. Prism-based compressors compensate only a small amount of dispersion compared to the typical values used in ultra-high-intensity laser systems [10]. To compress a stretched, amplified pulse of a duration of several hundred picoseconds, the required physical dimensions render their use impractical. On the other hand, grating stretchers (compressors) that provide positive (negative) chirp have been widely employed in traditional high-intensity CPA systems [11]. However, a lower grating efficiency in the compressor (typically 50–70%) results in a considerable energy loss of the amplified pulse. In contrast, a bulk material compressor with positive dispersion offers the advantage of broadband high-transmission efficiency (typically >90%) and facilitates alignment. In order to use an optical glass compressor, a grating-and-prism, so-called grism stretcher is selected as a negative dispersion