Earth, Physical and Quantum Sciences
16:05 - 17:25 | Meeting Room 3 (Level 0)
Chair: Prof. Luciano Mule'Stagno
Mr Daniele Caruana
Department of Geosciences | Department of Physics, Faculty of Science
Seismic monitoring is typically limited to traditional land-based seismic networks, leaving the vast offshore areas without any instrumentation. In recent years, submarine fibre-optic communication cables are being considered for use as a new type of instrument able to detect vibrations on the seabed. Such vibrations can originate from earthquakes or from other processes, such as marine landslides or tsunamis. Thus, the fibre cables crossing the ocean floors offer a promising opportunity to extend the existing seismic networks by acting as sensitive detectors of environmental and geophysical signals.
We apply laser interferometry to a 260 km submarine optical fibre link between Malta and Sicily that is actively used for telecommunications. An ultra-narrow-linewidth laser source is transmitted through the fibre, where external perturbations such as seismic waves induce strain throughout the fibre, which in turn leads to measurable phase fluctuations in the transmitted light. Signal processing and interpretation techniques are used to separate seismic signatures from environmental and anthropogenic noise, allowing geophysical information to be extracted and monitored. We detect earthquakes ranging from magnitude 1.5 to 8, with events observed at distances up to 16,000 km, depending on noise conditions. In addition to seismic activity, the system is sensitive to other environmental signals, such as storms and certain anthropogenic sources of noise. This work is conducted within the Horizon-Europe-funded SENSEI project, which aims to leverage existing fibre-optic communication networks into distributed sensors for environmental and geophysical monitoring.
Mr Luke Said
Department of Geosciences, Faculty of Science
The Maltese Islands are situated within the complex tectonic setting of the Sicily Channel Rift Zone, where small to moderate earthquakes occur frequently but are often poorly constrained due to their low magnitudes, sparse instrumentation, and limitations in existing processing techniques. This project aims to enhance local earthquake detection, location, and characterisation capabilities by developing improved automated single-station seismic analysis tools.
A new software package written in Python is being developed to automatically detect earthquake signals using targeted frequency filter bands to enhance the signal-to-noise ratio. Earthquake phase arrivals are identified from amplitude-triggered detections and subsequently clustered into P- and S-wave phases. The direction of the earthquake is determined from P-wave polarisation analysis, while the source-to-station distance is estimated from the S-P arrival time, followed by magnitude estimation. A graphical user interface provides tools for analysts to assess processing results, evaluate the quality of earthquake locations and magnitudes, and perform manual phase picking where reprocessing is required.
The new code is currently being tested against previously published earthquake catalogues for Malta. It will then be applied to newly processed data to compile an updated earthquake catalogue. Seismic data from the Malta Seismic Network, operated by the Seismic Monitoring and Research Group within the Department of Geosciences, are being analysed. This new tool will improve seismic monitoring capabilities and will contribute to regional seismotectonic studies, ultimately supporting improved seismic hazard assessment for Malta. This research is funded by the UM’s Research Excellence Fund.
Dr Oluwatimilehin Benjamin Balogun
Department of Geosciences, Faculty of Science
A holistic examination of the tectonic architecture of the Mediterranean was carried out by integrating gravity and seismological data to create an improved tectonic framework capable of providing more insights into the complex microplate interactions, associated seismic risks, and the long-term geodynamic evolution of the region. The methods involved the extraction of linear geological features from Bouguer and free-air anomaly gravity data through gradient computations and qualitative analyses of the focal mechanism derived from a compilation of seismic activity over the past 12 years.
The tectonic evolution of the Iberian microplate was revealed to be controlled by at least three primary markers: a Western and Central onshore–offshore radial fault network linked to the Central Atlantic Magmatic Province of Southern Portugal, interpreted as a rift system precursor to Pangea breakup; the Bay of Biscay–Pyrenees fault zone forming the northern boundary of the Iberian microplate; and the Atlas–Gibraltar Arc system representing the Iberia–Africa plate boundary, with active deformation concentrated along the Alboran Ridge and North Saharan Flexure.
In the Central Mediterranean, discrete and highly deformed boundaries characterised the Adriatic, Calabrian, Ionian, Carpathian, and Aegean tectonic units. Identified at a distance of approximately 103km due East of Malta is a three-unit junction connecting the Calabria, Adriatic and Ionian tectonic units. Farther east, the East Anatolian, North Anatolian, Caucasus, and the Cypriot arc fault systems collectively define a complex fault network linking the Mediterranean to Eurasia. The results emphasise long-lived inheritance, regional faulting, and microplate fragmentation as major controls on Mediterranean tectonic evolution.
Prof. Alessio Magro
Institute of Space Sciences and Astronomy
Fast Radio Bursts (FRBs) are millisecond-duration radio transients that offer powerful probes of the intergalactic medium, compact objects, and cosmology. Their short timescales and unpredictable nature require low-latency, high-throughput backends capable of processing large data volumes in real time and triggering rapid follow-up observations.
In this talk, we present the design and implementation of a new real-time FRB digital backend developed by UM for the upgraded Medicina Northern Cross radio telescope. The Northern Cross, a large transit interferometer operating around 400 MHz, is currently undergoing a major digital and high-performance computing upgrade that dramatically increases the number of receivers, formed beams, and instantaneous data rates. Exploiting this capability requires a scalable backend able to ingest, beamform, and continuously search wide-field data streams with minimal latency.
We describe a modular, GPU-accelerated architecture that combines high-throughput data acquisition, real-time beamforming and correlation, and distributed orchestration for synchronising multiple compute nodes. The backend is designed to deliver synthesised beams directly to an FRB search pipeline while maintaining precise timing alignment across heterogeneous processing stages. Benchmark results demonstrate faster-than-real-time performance for both beamforming and correlation, providing sufficient headroom to scale to the full instrument configuration.
This system establishes the technological foundation for continuous, wide-field FRB surveys with the Northern Cross, enabling rapid candidate identification, triggered voltage capture, and timely multi-wavelength follow-up. Beyond FRB science, the backend represents a general-purpose real-time processing framework for next-generation radio facilities, highlighting the roles of GPU computing and distributed orchestration in modern transient astronomy.
Dr Veronica Gonzalez
Institute for Sustainable Energy
To maximise power conversion efficiency (PCE) in a monocrystalline silicon solar cell, it is essential to minimise defects that could serve as electron sinks. Nitrogen has long been recognised for its ability to suppress both interstitial and vacancy-related defects, as well as to promote oxygen precipitation. Unfortunately, because obtaining data in melted silicon (~1414°C) is challenging due to the high temperature, quantitative information on nitrogen's chemical and physical properties in silicon remains limited. Consequently, despite its known effectiveness in improving wafer properties, nitrogen doping is less common compared to other doping techniques. In this project, we focused on collecting data about how nitrogen interacts with defects and grown-in oxygen precipitates at temperatures near silicon's melting point, to determine the optimal combination of time and temperature for doping silicon monocrystalline wafers with nitrogen. To this end, we proposed an innovative approach using integrated optical techniques, including light scattering tomography (LST) and Fourier transform infrared spectroscopy (FTIR). Random monocrystalline silicon wafers underwent several heat treatments in a nitrogen atmosphere and were characterised with the aim of developing a theoretical-experimental model for nitrogen diffusion in silicon and studying the mechanism by which nitrogen influences intrinsic defects.
Mr Aarón Piculo
Institute for Sustainable Energy
The SLICE (Silicon for Improved Cell Efficiency) project focuses on improving the quality of silicon crystals to enhance solar cell efficiency and manufacturing yield. Although crystal growth and cell fabrication are commercially established processes, this work involves the growth of gallium-doped silicon crystals specifically tailored for research purposes.
The scope of this project is to achieve a controlled range of defect densities, which are being characterised using standard laboratory techniques such as polishing, decorative etching, and infrared laser scattering tomography. These material-level defect metrics are systematically correlated with the photovoltaic performance of solar cells fabricated from the grown crystals. This study aims to provide insight into the relationships among gallium doping, defect engineering, and solar cell performance, along with supporting strategies to improve the efficiency of silicon-based photovoltaic devices.
The project is being carried out in collaboration with the Centre for Solar Energy Research and Applications at Middle East Technical University (ODTÜ-GÜNAM) and the industrial partner KalyonPV. Advanced silicon characterisation is being performed at UM’s Solar Research Laboratory, while ODTÜ-GÜNAM is providing state-of-the-art solar cell fabrication and efficiency testing. SLICE is a project financed by the Malta-TÜB陌TAK 2024 Joint Call for R&I Proposals.
Dr Ilia Khomchenko
Department of Physics, Faculty of Science
How can we describe fluctuations of physical observables in non-additive open quantum systems? The output of such systems is a fluctuating current that is characterised by its mean and variance, also known as current fluctuations. These quantities carry crucial information about the properties of these systems. One way to address this problem in the context of non-additive open quantum systems is to employ the concepts of quantum jump unravellings. Here, we show the breakdown of this approach for an open quantum system consisting of a pair of coupled quantum dots in contact with two reservoirs, described by an exact stochastic master equation. Namely, we demonstrate the limitations of the quantum jump approach in quantifying current fluctuations for a non-additive master equation in Lindblad form. However, for particular systems’ parameters, we demonstrate that this formalism enables us to reproduce current fluctuations. Investigating the dynamics of the system, we establish that the fluctuations of the stationary-state particle current can witness non-additivity of the asymptotic master equation. Our work lays the foundation for theoretical and experimental investigation of measurement in non-additive open quantum systems.
Dr Davide Benedetto Tiz
Department of Chemistry, Faculty of Science
White light emitting (WLE) materials have attracted considerable attention due to their commercial and societal applications in video displays and lighting devices. They are characterised by a fluorescence emission profile between 380 nm and 700 nm. In the past, WLE systems have relied on three coloured components (red, green and blue) to produce white light. Our lab is currently developing intelligent WLE fluorescent molecules based on pyrazoline-naphthalimide dyes as single WLE organic molecules. The molecules are synthesised by a multi-step procedure by Friedel–Crafts acylation to produce acetylnaphthalene, which is then oxidised to yield 1,8-naphthalic anhydride. Condensation with a primary amine affords an N-substituted-1,8-naphthalimide, which is followed by a Claisen–Schmidt condensation with a substituted aldehyde to form a chalcone intermediate. Cyclisation with different hydrazine derivatives yields pyrazoline-naphthylamides. By selective coordination of various chemical inputs, such as magnesium (Mg²鈦�), sodium (Na鈦�), and protons (H鈦�), the emission colour of the molecules can be tuned. Under specific conditions, the combined emission from the pyrazoline and naphthalimide fragments produces white light, or alternatively, the emission can be turned ‘off’. The photonic devices function as a multi鈥恑nput, reconfigurable molecular logic gate that converts specific ionic stimuli into optical outputs. The ‘lab-on-a-molecule’ integrates sensing, signal processing and reporting functions within a single molecular framework.