We present an experimental study of molecular alignment echoes driven by ultrashort structured light fields carrying orbital angular momentum (OAM). By combining two time-delayed pump pulses with spatially varying polarization, we produce a molecular "q plate" in a gaseous CO_{2} sample that can be rephased in a controllable manner. This approach enables the storage of OAM information within the rotational coherences of molecules and its retrieval at adjustable times. The concept is validated using vortex beams of various topological charges ℓ=±1, 2. These results extend the mechanism of molecular alignment echoes to vector light fields and establish a new route for optical processing of ultrashort OAM pulses, advancing molecular-based quantum interfaces for structured light.
This paper presents an embedded multi-modal vision system for drone detection, combining an event-based camera, an IMU, and an RGB sensor. The method leverages an attentional mechanism on the event stream and is robust to rotations along all three axes (roll, pitch, and yaw) of a rotating platform. The event-based sensor enables localization of fast moving objects, while the RGB camera provides classification, with the entire system optimized for embedded computational constraints. Performance analysis, with and without attention mechanisms and across various algorithmic variants, assesses the trade-off between computational cost and detection accuracy. The study identifies optimal operating situation for each configuration, validated on an outdoor test data samples.
This paper introduces a robotic assistance system for minimally invasive middle ear surgery, focusing on precise access to the tympanic membrane. The system combines a 7-degree-of-freedom robotic arm with a hybrid visual servoing framework that integrates position-based and image-based control strategies. Dual visual feedback from a color camera and an endoscope enables robust 6-DoF pose estimation and sub-millimetric tool guidance. A model-based tracker and blob detection ensure accurate alignment and targeting, while a Quadratic Programming controller enforces safety constraints such as maintaining the field of view. The approach is validated through simulations and real-world experiments, demonstrating high accuracy, robustness to anatomical variability, and suitability for clinical integration. This work advances robotic microsurgery by providing a closed-loop, constraint-aware control architecture tailored for otologic procedures.
A nonlinear optical loop mirror (NOLM) is an optical component commonly used to shape the temporal profile of guided light waves in a large number of optical systems. Although the NOLM is an inherently multifunctional device, in all its practical applications this device is still designed to provide a single functionality. Here we show that the NOLM can be designed to provide multiple functions and make a complex optical system more efficient and competitive. In particular, we show that in a mode-locked laser cavity the NOLM can be designed to serve as a mode-locking element in the transient regime of the laser, and as a power regulator in the stationary regime. While the conventional architecture of a NOLM is usually built from nontunable components, our multifunctional NOLM is built with tunable components offering great flexibility in setting the device's transfer function, and therefore the ability to access different types of optical functions such as pulse regeneration, power regulation, or mode locking in laser cavities.
