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Research has demonstrated that zeolite nucleation and growth can be controlled by fine-tuning chemical composition, temperature, and pressure, resulting in structures with diverse porosities and functionalities. Nevertheless, current energy delivery methods lack the finesse required to operate on the femto- and picosecond timescales of silica polymerisation and depolymerisation, limiting their ability to direct synthesis with high precision. To overcome this limitation, we introduce an ultrafast laser synthesis technique capable of delivering energy at these timescales with unprecedented spatiotemporal precision. Unlike conventional or emerging approaches, this method bypasses the need for specific temperature and pressure settings, as nucleation and growth are governed by dynamic phenomena arising from nonlinear light-matter interactions, such as convective flows, cavitation bubbles, plasma formation, and shock waves. These processes can be initiated, paused, and resumed within fractions of a second, effectively freezing structures at any stage of self-assembly. Using this approach, we traced the entire nucleation and growth pathway of laser-synthesized TPA-silicate-1 zeolites, from early oligomer formation to fully developed crystals. The unprecedented spatiotemporal control of this technique unlocks new avenues for manipulating reaction pathways and exploring the vast configurational space of zeolites., Comment: main text, 6 figures, 4 video files, supplementary information

Standard optical tweezers rely on optical forces that arise when a focused laser beam interacts with a microscopic particle: scattering forces, which push the particle along the beam direction, and gradient forces, which attract it towards the high-intensity focal spot. Importantly, the incoming laser beam is not affected by the particle position because the particle is \emph{outside} the laser cavity. Here, we demonstrate that \emph{intracavity nonlinear feedback forces} emerge when the particle is placed \emph{inside} the optical cavity, resulting in orders-of-magnitude higher confinement along the three axes per unit laser intensity on the sample. We present a toy model that intuitively explains how the microparticle position and the laser power become nonlinearly coupled: The loss of the laser cavity depends on the particle position due to scattering, so the laser intensity grows whenever the particle tries to escape. This scheme allows trapping at very low numerical apertures and reduces the laser intensity to which the particle is exposed by two orders of magnitude compared to a standard 3D optical tweezers. We experimentally realize this concept by optically trapping microscopic polystyrene and silica particles inside the ring cavity of a fiber laser. These results are highly relevant for many applications requiring manipulation of samples that are subject to photodamage, such as in biological systems and nanosciences., Comment: 11 pages, 6 figures

We report on the studies of switching mechanism between normal and anomalous laser induced periodic surface structures. We have shown that for high loss metals the switching mechanism between normal and anomalous modes relays on an interplay between two different feedbacks inherent into the structure formation process: long range, low intensity dipole-like scattering of light along the surface, which governs anomalous ripples parallel to the laser polarization, and short range, high intensity plasmon-polariton wave, which is initiated by near field dipole radiation and responsible for creation of ripples perpendicular to the polarization, i. e. normal structure. By managing these two feedbacks, we demonstrated creation of both normal and anomalous laser induced periodic surface structures on the same surface. In contrast to the previous studies, we have shown that the thermal oxidation mechanism can form both normal and anomalous types of the structure, while the ablation mechanism is involved only during the normal structure formation. Unlike the formation of oxidation type anomalous structure, the formation of ablation type normal structure does not have inherent negative feedback, which is self-regulating nano-ripples formation. This feedback needs to be applied artificially, by regulating scanning speed and pulse energy at a given repetition rate of the laser. With implementation of nonlinear laser lithography technique for ablation type of normal laser induced periodic surface structures we demonstrated large area high regular nano-grating formation on different surfaces with extremely high industrially acceptable speed.