The paper describes a number of research projects of the Faculty of Mechatronics of Warsaw University of Technology in order to illustrate the use of common mechatronics and optomechatronics approach in solving multidisciplinary technical problems. Projects on sensors development, measurement and industrial control systems, multimodal data capture and advance systems for monitoring and diagnostics of industrial processes are presented and discussed.
Organometallic complexes comprising of a platinum (II) acetylide core linked with different -conjugated chromophores are promising materials for applications requiring strong nonlinear-optical response. In dual-mode optical power limiting, the chromophore first undergoes ultrafast two-photon absorption (2PA) in singlet manifold, followed by efficient intersystem crossing (ISC) and subsequent T-T absorption. While the heavy atom facilitates efficient T-T absorption, achieving sufficiently high intrinsic 2PA cross-section value has remained an issue. Here we present a series of linear- and cross-conjugated p-phenylene vinylene platinum (II) acetylides (TPV1-Ph, TP01-TPV2, crossTPV1, crossTPV1-DPAF, crossTPV3) with extended π-conjugated chains and discuss their linear- and nonlinear photophysical properties, including comparison to the properties of the constituting ligand chromophores. Remarkably high femtosecond 2PA cross-section values (up to 10,000 GM) were obtained for several of the new complexes by both nonlinear transmission (NLT) and two-photon excited fluorescence (2PEF) method. The large 2PA values, especially in crossTPV1 and crossTPV3, span a broad range of wavelengths, 570 – 810 nm, which overlaps with maximum wavelength of strong T-T excited state absorption measured by nanosecond transient absorption method. This combination of properties renders these compounds efficient dual-mode nonlinear absorbers in the visible to near-IR region. Examination of the photophysical properties allows us to elucidate the structure-property relationships both in the solutions as well as in solid samples where the chromophores are incorporated into a polymer host.
Numerical simulations and analysis of a very efficient and stable non-collinear Optical Parametric Chirped Pulse
Amplification (OPCPA) femtosecond system are presented. The system is optimized for a long (nanosecond),
rectangular temporal profile and a flat-top spatial profile of the pump laser pulse. We show that a two stage
system consisting of a multipass preamplifier and a time-sheared power amplifier operating around 850 nm and
pumped by a 532 nm pulse can amplify pulses directly from a femtosecond oscillator up to multi-terawat levels
with quantum efficiencies as high as 0.9. We also discuss practical schemes of the few-cycle multi-terawatt
OPCPA systems employing different nonlinear crystals. The results of the Monte-Carlo simulations are used to
balance the stability and efficiency of the parametric amplifier system.