M.T. Flores-Arias

• PhD in Physics
• Professor (Associate) at University of Santiago de Compostela

The dynamic interaction between cells and their substrate is a cornerstone of biomaterial‐based tissue regeneration focused on unraveling the complex factors that govern this crucial relationship. A key challenge is translating physical cues from 2D to 3D due to limitations in current biofabrication techniques. In response, this study introduces an...

Polydimethylsiloxane (PDMS) is extensively used to fabricate biocompatible microfluidic systems due to its favorable properties for cell culture. Recently, ultraviolet-curable PDMS (UV-PDMS) has shown potential for enhancing manufacturing processes and final optical quality while retaining the benefits of traditional thermally cured PDMS. This stud...

The Belousov–Zhabotinsky (BZ) reaction has long been a paradigmatic system for studying chemical oscillations. Here, we experimentally studied the synchronization control within photochemically coupled star networks of BZ oscillators. Experiments were carried out in wells performed in soda-lime glass constructed using novel laser technologies. Util...

Achieving efficient mixing of fluids is a great challenge in microfluidics that has been addressed using microstructures. In this work, Stereolithography (SLA) and Pulsed Laser Ablation (PLA) were combined to manufacture a straight micromixer for uniform mixing of fluids. Computational Fluid Dynamics (CFD) simulation was performed to test the devic...

This contribution reports the organization of a scientific conference organized by Luzada and OSAL after last year's success: the "II Northwestern Meeting of Young Researchers in Optics (II NW MYRO)". These two teams work on spreading optics and photonics to society.

This contribution reports the organization and celebration after the Covid-19 pandemic of a singular scientific conference focused on early-career researchers from the Spanish universities of Santiago de Compostela and Salamanca: the “I Northwest Meeting of Young Researchers in Optics (I NW MYRO)”.

Synchronization control of complex systems is a field that emerged with huge interest and aims to study new possible routes to synchronization in networks of non-locally coupled chemical oscillators. Light can be used to stimulate these systems and to be able to synchronize the different micro-reactors involved in the complex system. To this end, t...

Industrial quality applications of high-power lasers working at high repetition rates, including laserdriven particle acceleration, will require laser systems capable of operating in a stable and prolonged manner. Several factors can affect this stability, including the environment conditions, such as temperature or humidity, and the progressive he...

Novel cell culture platforms, with more physiological surface roughness, require different technologies capable of precisely micropattern substrates. 3D printing offers a considerable accuracy and user-friendly procedures. For its part, pulsed laser ablation proves to be a versatile technology to perform detailed surface micropatterning. In this wo...

Subaquatic indirect Laser-Induced Plasma-Assisted Ablation (SLIPAA) is proposed as a laser-based technique for glass processing. In this configuration, a water layer is added between a metallic target and a soda-lime glass substrate, so the processing of the glass is due to a combination of the ablation mechanism, the shock waves, and the cavitatio...

Diabetes is associated with a high mortality rate due to vascular complications. Chronic hyperglycemia in diabetes leads to enhanced oxidative stress and glycation. Here, we explored the impact of glycation on human erythrocyte characteristics and capacity to affect endothelial cell function following erythrophagocytosis. Native and glucose-mediate...

Microfluidic devices have been widely developed in the last decades because of the huge number of fields where they can be applied. Among all the different fabrication techniques available, laser direct writing stands out since it is a fast, accurate, versatile and non-contact method. It is particularly well-suited when working with glass, a robust...

Internal channels are one of the most interesting structures to implement in microfluidics devices. Unfortunately, the optical technologies typically used in microfluidics, such as photolithography or reactive ion etching, are unable to generate these structures by only allowing surface structuring. Stereolithographic 3D printing has emerged as a v...

Homing of circulating tumour cells (CTC) at distant sites represents a critical event in metastasis dissemination. In addition to physical entrapment, probably responsible of the majority of the homing events, the vascular system provides with geometrical factors that govern the flow biomechanics and impact on the fate of the CTC. Here we mathemati...

Stereolithographic printers have revolutionized many manufacturing processes with its capacity to easily produce highly detailed structures. In the field of microfluidics, this technique avoids the use of complex steps and equipment of the conventional technologies. The potential of low force stereolithography technology is analysed for the first t...

3D printing has revolutionized the field of microfluidics manufacturing by simplifying the typical processes offering a considerable accuracy and user-friendly procedures. For its part, laser ablation proves to be a versatile technology to perform detailed surface micropatterning. A hybrid technique that combines both technologies is proposed, empl...

Since the advent of the COVID-19 pandemic, face-to-face outreach has been gradually replaced by dissemination through social networks. However, the use of social networks for outreaching is not easy since there is an important risk of biasing the communication by converting it into an exclusively one-way channel. In this contribution, we explain ho...

In this contribution we show how, in times of pandemic, outreach activities driven by social networks can be a successful alternative to face-to-face events. Designing each activity to properly suit the host platform ensures success.

The SARS-CoV-2 pandemic has led to a global decrease in personal protective equipment (PPE), especially filtering facepiece respirators (FFRs). Ultraviolet-C wavelength is a promising way of decontamination, however adequate dosimetry is needed to ensure balance between over and underexposed areas and provide reliable results. Our study demonstrate...

Peer-reviewed publication DOI: 10.1080/15459624.2020.1786576. Background and Objectives: The SARS-CoV2 pandemic has lead to a global decrease in protection ware, especially facepiece filtering respirators (FFRs). Ultraviolet-C wavelength is a promising way of descontamination, however adequate dosimetry is needed to ensure balance between over an...

This work introduces a new approach to prepare active GRadient-INdex (GRIN) materials by gradually doping commercial silica cylindrical substrates with different optically active ions or materials by the Laser Zone Melting (LZM) process. Scanning Electron Microscopy (SEM) combined with energy dispersive X-ray (EDX) analysis demonstrate that the dop...

Ion acceleration in the MeV range can be routinely achieved with table-top laser technology. One of the current challenges is to improve the energy coupling from the laser to the proton beam without increasing the laser peak power. Introducing nanostructures at the front target surface was shown to be beneficial for an efficient transfer of energy...

Ion acceleration in the MeV range can be routinely achieved with table-top laser technology. One of the current challenges is to improve the energy coupling from the laser to the proton beam without increasing the laser peak power. Introducing nanostructures at the front target surface was shown to be beneficial for an efficient transfer of energy...

We report a novel scheme to generate laser-induced, ultrafast, intense (Tesla scale) magnetic fields. Three-dimensional particle-in-cell simulations show that a femtosecond azimuthally-polarized infrared vector beam, aimed to a conducting circular aperture, produces an intense axially polarized tip-shaped femtosecond magnetic field, extending over...

We report a novel scheme to generate laser-induced, ultrafast, intense (Tesla scale), spatially isolated, magnetic fields. Three-dimensional particle-in-cell simulations show that a femtosecond azimuthally-polarized infrared vector beam, aimed to a conducting circular aperture, produces an intense axially polarized tip-shaped femtosecond magnetic f...

The interaction of high-intensity laser pulses and solid targets provides a promising way to create compact, tunable, and bright XUV attosecond sources that can become a unique tool for a variety of applications. However, it is important to control the polarization state of this XUV radiation and to do so in the most efficient regime of generation....

Present work describes the radiation quality and dosimetric characterization performed on the micromachining station of the femtosecond STELA (Santiago TErawattLAser) of the University of Santiago de Compostela (Spain). For this aim, ionisation chambers, solid state detectors and radiochromic films were used. The results show the emission of pulsed...

Understanding hemodynamics in blood circulation is crucial in order to unveil the mechanisms underlying the formation of stenosis and atherosclerosis. In fact, there are experimental evidences pointing out to the existence of some given vessel configurations that are more likely to develop the above mentioned pathologies. Along this manuscript, we...

We report on physical sensors based on microbubble and micro-disc whispering gallery mode resonators. We characterized the resonators, improved the mitigation of fluctuations, and developed a pressure, temperature and THz bolometer.

Plasmon resonances are known to amplify the electromagnetic fields near metallic nanostructures, providing a promising scheme to generate extreme-ultraviolet harmonics using low power drivings. During high-order harmonic generation (HHG), the driving and harmonic fields accumulate a phase difference as they propagate through the target. In a typica...

The interaction of high-intensity laser pulses and solid targets provides a promising way to create compact, tunable and bright XUV attosecond sources that can become a unique tool for a variety of applications. However, it is important to control the polarization state of this XUV radiation, and to do so in the most efficient regime of generation....

In this work a method for fabricating functionalized preclinical devices is presented. The manufacturing process combines a laser indirect writing technique to fabricate a soda-lime glass master and soft-lithography methods to obtain the final structure in polydimethylsiloxane (PDMS). The roughness of the device is modified in a controlled manner b...

We present the isolation of single attosecond pulses for multi-cycle and few-cycle laser pulses from high harmonic generation in overdense plasmas, calculated with particle-in-cell simulations. By the combination of two laser pulses of equal amplitude and a small frequency shift between them, we demonstrate that it is possible to shorten the region...

A method to generate a polarization gate for multicycle laser pulses is presented. We study the performance of a pulse with time-dependent polarization to produce a single attosecond pulse after its interaction with an overdense plasma. The polarization gate is generated through the use of cross-polarized wave generation in a single crystal combine...

This study presents a Laser Zone Melting method with potential for producing planar waveguides at large scale, based on the surface coupling of two chemically compatible glass layers which exhibit distinct indices of refraction. The method is based on a recent patent, particularly applicable to process glass and ceramics with low thermal shock resi...

The interaction of ultrashort, high intensity laser pulses with thin foil targets leads to ion acceleration on the target rear surface. To make this ion source useful for applications, it is important to optimize the transfer of energy from the laser into the accelerated ions. One of the most promising ways to achieve this consists in engineering t...

A laser based technique for microstructuring titanium and tantalum substrates using the Talbot effect and an array of microlenses is presented. By using this hybrid technique; we are able to generate different patterns and geometries on the top surfaces of the biomaterials. The Talbot effect allows us to rapidly make microstructuring, solving the c...

Microchannels fabrication by laser direct writing over soda-lime glass is presented. Three different laser in the IR are employed working on different temporal regimes. Differences among them are evaluated in terms of their topological surfaces

Plasmon resonances are known to amplify the electromagnetic fields near metallic nanostructures. Therefore, they are considered to provide a promising scheme to generate extreme-ultraviolet harmonics, using low power drivings. During high-order harmonic generation (HHG), the driving and harmonic fields accumulate a phase difference as they propagat...

The interaction of ultrashort, high intensity laser pulses with thin foil targets leads to ion acceleration on the target rear surface. To make this ion source useful for applications, it is important to optimize the transfer of energy from the laser into the accelerated ions. One of the most promising ways to achieve this consists in engineering t...

A study of PDMS (polydimethylsiloxane) sol-gel–coated channels fabricated using soft lithography and a laser direct writing technique is presented. PDMS is a biocompatible material that presents a high versatility to reproduce several structures. It is widely employed in the fabrication of preclinical devices due to its advantages but it presents a...

El desarrollo de aplicaciones virtuales para la enseñanza estáa cobrando cada vez más importancia dentro de las aulas. Estas applets facilitan a los estudiantes la comprensión de aquellos contenidos que presentan una mayor dicultad, actuando como laboratorios virtuales. En ellos pueden implementar experimentos que de otra forma no podrían realizar...

En este trabajo se presentan dos Interfaces Gráficas de Usuario (GUIs) para la enseñanza de diversos conceptos relacionados con la asignatura de Óptica Coherente que se imparte en el máster de Fotónica y Tecnología del Láaser de la Universidad de Santiago de Compostela. Las GUIs estáan desarrolladas con el entorno de programación visual de MATLAB c...

A VIRTUAL BENCH TO EXPLAIN GEOMETRIC OPTICS USING MATLAB GUIDE ENVIRONMENT A.I. Gómez-Varela ¹, F.S. Vara ², N. Barreira Rodríguez ³, M. Ortega Hortas ³, J. Novo Buján ³, M.G. Penedo ³, M.T. Flores-Arias ¹, C. Bao-Varela ¹ 1Universidad de Santiago de Compostela (SPAIN) 2Colegio Hogar de Santa Margarita (SPAIN) 3Universidad de A Coruña (SPAIN) In...

In this work, we report a comparative study of the laser ablation threshold of borosilicate, fused silica, sapphire, and soda-lime glass as a function of the pulse width and for IR laser wavelengths. We determine the ablation threshold for three different pulse durations: , 10 ps, and 20 ns. Experiments have been performed using a single laser puls...

We present a laser based technique combined with the Talbot effect for microstructuring surfaces. The use of the Talbot effect is introduced as a solution to avoid damage of the periodic object used for micropattering different surfaces during the ablation process. The fabrication of two periodic objects (a mask and a microlens array) for micropatt...

Gold nanorods (GNRs) were initially prepared with 3 different aspect ratios (2.5, 2.9 and 3.8) via a seed-mediated chemical route, using cetyltrimethylammonium bromide (CTAB) as organic surfactant. These rods were then irradiated under continuous-wave (λ=1064 nm) and pulsed (λ=1064, 532, 355 nm) emission modes using Nd:YVO4 and Nd:YAG lasers, respe...

We propose a laser-based method for fabricating microlens on borosilicate glass substrates. The technique is composed by a laser direct-write technique using a Nd : YVO 4 for fabricating the microlens arrays and a post thermal treatment with a CO 2 laser for improving its morphological and optical properties. The proposed technique will allow us to...

The 23rd Congress of the International Commission for Optics (ICO) was held in Santiago de Compostela (Spain) 26–29 August 2014, organized by the Universities of Vigo and Santiago de Compostela. Approximately 450 people attended the conference, sharing their knowledge in the cheerful, warm atmosphere of this lovely city. The conference was extremel...

The USC-OSA is a student chapter located at the University of Santiago de Compostela (Spain) whose objective is to bring optics and photonics knowledge closer to general public. In order to arouse kids' interest in Optics we developed an activity called Funny Light. This activity consisted on a visit of some USC-OSA members to a several local prima...

In this work, SiO2-TiO2 films doped with erbium were prepared by dip-coating sol-gel process onto commercial glass substrates. The surface morphology of the films was characterized using Atomic Force Microscopy while thickness, refractive index, extinction coefficient and porosity of the films were determined by ellipsometric measurements in a wave...

A new method for fabricating microchannels for microfluidic applications on soda-lime glass has been developed. It consists of a combination of a laser direct write technique for fabricating the microchannels and a thermal treatment for reshaping and/or improving the morphological qualities of the generated microchannels. The proposed technique all...

Este documento presenta un nuevo procedimiento para el cálculo de las aberraciones de tercer orden en los cristalinos con gradiente de índice (GRIN), que combina un método numérico iterativo con la teoría de Hamilton sobre aberraciones, en términos de dos rayos paraxiales con condiciones de contorno sobre superficies generales con límite curvado, y...

The present paper considers two gain GRIN media, characterized by a complex parabolic and hyperbolic secant refractive index profile, for the design of uniform beam shaper systems. A general condition for beam shaping is obtained from the equation describing the evolution of the half-width of a plane Gaussian beam in the GRIN media. The simulation...

USC-OSA is a student chapter whose objective is to bring Optics knowledge closer to the non-optics community. The activity developed at the Hospital school was one of the most important last year. It was consisted in a few Optics experiments and workshops with hospitalized children of different ages and pathologies. The experiments had to be adapte...

In this paper, we study the reduction in the fluence ablation threshold induced by tin impurities incorporated in float soda-lime glass during the fabrication process. The laser system used in the experiments was a laser operating at 1064 nm with a pulse duration of 20 ns. The fluence ablation thresholds found were for the tin side and for the tin-...

Geometrically controlled, channel-like structures were prepared on commercial, soda-lime glass substrates, by a Laser Ablation Backwriting (LAB) process using a commercial Nd:YVO4 laser fitted with a beam steering galvanometer mirror unit. 70Cu30Zn Brass alloy, Ag and Al metal targets were evaporated onto glass substrates by simple irradiation thro...

Active GRIN rod lenses, described by both complex gradient parameter and parabolic refractive index profile, are a suitable solution for laser beam shaping purposes. This study is the first step towards preparation of these active GRIN materials by gradually doping commercial silica rods with different inorganic compounds based on oxides and/or car...

Commercial soda-lime float glass exhibits the incorporation of tin impurities during the fabrication process. The influence of these impurities as enhancement mechanism for the ablation process is investigated and reported here. Energy dispersive x-ray analysis revealed the presence of tin (Sn) only on one side of the glass. Based on this, laser ab...

In this paper we present an active GRadient-INdex (GRIN) beam shaper with gain for Gaussian to flat-top beam conversion. This extra-cavity beam shaper is based in the proper design of an active GRIN selfoc rod microlens in order to perform the beam shaping operation. General condition for obtaining beam shaping by active GRIN rod microlenses is sho...

Inorganic and hybrid sols obtained from Si, Ti, Zr and Ce organometallic precursors were used to prepare single and multilayer coatings with different thicknesses. Planar step-index waveguides with different refractive indices were thus prepared by dip-coating the above sols onto commercial soda-lime glass substrates, followed by appropriate therma...

The unification of the new European studies under the Bologna process creates a new adaptation within the field of Physics. An adjustment to the programs is required to migrate to the new European Credit Transfer (ECTS). According to the article 12.2 of the R.D. 1393/2007, the Physics Degree at the University of Santiago de Compostela (USC), Spain,...

The USC-OSA Student Chapter has been constituted in March 2013 by members of the University of Santiago de Compostela (USC) in Spain and sponsored by The Optical Society of America (OSA). It is formed by five graduate and one undergraduate students with the common interest in Optics and Photonics research and a professor of the USC is also involved...

NEMO was the “Network of Excellence in Micro-Optics” granted in the “Sixth Framework Program” of the European Union. It aimed at providing Europe with a complete Micro-Optics food-chain, by setting up centers for optical modeling and design; measurement and instrumentation; mastering, prototyping and replication; integration and packaging and relia...

The Galician Universitary System (SUG) in the framework of the European studies under the Bologna process presents a huge number of Masters courses. In this work we present the teaching framework of the Science Masters on “Photonic and Laser Technologies”, coordinated by the University of Vigo (UVigo) and involving the three Universities of Galicia...

This work presents a theoretical analysis as well as the simulation of different optical functions that can be obtained from Gaussian beam transformations by active GRIN (GRadient-INdex) rod lenses having quadratic gain or loss. Profiles of the real and imaginary parts of the complex refractive index have been studied in order to show guidance beha...

The preparation of planar waveguides has attracted considerable attention because of their potential applications in photonics, particularly in the field of communications and data transmission, as well as in the development of novel sensors. Ion-exchange and chemical or physical vapour deposition methods have been extensively used to develop this...

The advantages of planar glass waveguides and their preparation via Laser Ablation Backwriting (LAB) of metal targets have been extensively discussed in recent years. Moreover, LAB has also been applied to the successful fabrication of optical phase diffraction gratings and may be considered as a convenient method for the preparation of elements us...

Guías de onda planas de SiO2:TiO2 en proporción 70:30 han sido preparadas sobre substratos de vidrio comercial mediante una técnica sol-gel combinada con deposiciones por inmersión. Las estructuras mono y multicapa desarrolladas son caracterizadas ópticamente empleando distintas técnicas. Estos recubrimientos son caracterizados ópticamente mediante...

Tri-dimensional structures were internally mechanized into polymeric plates of polycarbonate (PC) and polyethyleneterefthalate (PET) by a laser backwriting process performed with plates submerged in water. A Nd:YVO 4 laser emitting at fundamental wavelength (1064 nm) in nanopulsed regime was employed. http://ecio-conference.org/2012/paper/ECIO-201...

Since frictional interactions in microscopically small components are becoming increasingly important for the development of new products for all modern technology, we present a laser-based technique for micro-patterning surfaces of materials using low-cost microlens arrays. The microlens used were fabricated on soda-lime glass using a laser direct...