OPCPA: From Concept to Ultrafast Future
The first proof-of-concept experiment on stretching, amplification, and compression of chirped pulses in an optical parametric amplifier (OPA) was demonstrated in 1992. This experiment was performed by a Vilnius University research group led by Light Conversion co-founder Prof. Algis Petras Piskarskas.
In the 1970s Prof. Gérard Mourou and Prof. Donna Strickland invented a “method of generating high-intensity, ultra-short optical pulses.” This chirped pulse amplification (CPA) method revolutionized the laser science and earned the pair a share in the Nobel Prize for Physics in 2018.
The CPA method finally enabled the increase in power of ultra-short pulses without causing any optical damage to the lasing medium itself. This discovery created the potential for new applications in laser science — from studying fundamental physics principles to treating deep-tissue brain cancer or performing laser vision corrections.
Why is CPA alone not enough?
As groundbreaking as the CPA method was, for some purposes, it is simply not sufficient. There are multiple scientific applications that require high-intensity pulses at different spectral ranges and a high repetition rate — properties that the CPA technique alone cannot offer.
It was Prof. A. Piskarskas, together with Prof. G. Jonušauskas and Prof. A. Dubietis, who published an article entitled, “Powerful femtosecond pulse generation by chirped and stretched pulse parametric amplification in BBO crystal.” This article explained the concept of Optical Parametric Chirped-Pulse Amplification (OPCPA). The team proposed that using high-energy pump pulses to amplify a chirped and stretched signal in OPA would allow boosting the power of femtosecond pulses up to a terawatt level. As a result, the OPCPA technology enabled scientists to create these high-intensity and high-repetition-rate properties, the ones that the CPA technique was lacking.
What makes OPCPA technology so desirable?
Since then, OPCPA has become a globally recognized and rapidly developing amplification technology for high-power, femtosecond pulse generation. Today, even more powerful systems have been demonstrated that are able to reach peak powers at a petawatt level.
Moreover, OPCPA technology has generated pulses characterized by not only ultrahigh power but by extremely short pulse duration as well. Such few-cycle pulses have been experimentally obtained in the visible (VIS), near-infrared (NIR), and mid-infrared (MIR) spectral ranges. Currently, the OPCPA is the only laser technology that simultaneously provides properties like high peak, average power and few-cycle pulse duration.
This technology provided a higher degree of flexibility and therefore amplified the already wide range of laser applications.
What Light Conversion offers regarding OPCPA
The company Light Conversion built its OPCPA systems using in-house-developed front ends, specifically PHAROS and CARBIDE femtosecond lasers. Both of these laser series offer industrial-grade stability and reliability. Thus enabling the ORPHEUS-OPCPA system to deliver few-cycle, CEP-stable pulses in a compact space.
Additionally, the same ORPHEUS-OPCPA system may also serve as a seed source for larger amplifiers. Due to inherently high-contrast output pulses, the ORPHEUS-OPCPA systems have been adopted as front ends in several ultra-high-intensity lasers. Certain advantages over other temporal contrast enhancement techniques made this adoption possible. Pulses with relatively high contrast (reached in OPAs) are further amplified in laser amplifiers up to ultra-high energies. This allows the delivery of background-free pulses with near-single-cycle bandwidth, excellent spectral phase coherence, and CEP stability.
What is next on Light Conversion’s agenda?
Since the development of the SYLOS at ELI-ALPS, the company has produced over five high-energy OPCPAs with sub-10 femtosecond pulses reaching hundreds of millijoules. Multiple table-top ORPHEUS-OPCPAs were also produced. These products are being applied in a range of high-energy attosecond pulse generation, laser electron acceleration, and nuclear waste decomposition.
To request more information or a quotation for Light Conversion products, contact IL Photonics.