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PHY3200 Physics Project Titles
Academic Year 2016-17
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Project Title:
Analysis of new auxetics structures
Supervisors:
Co-supervisor:
Dr Pierre-Sandre Farrugia
Dr Ruben Gatt
Abstract:
Auxetic materials exhibit the counterintuitive behaviour of
expanding laterally in one or more directions when stretched.
Similarly, they contract laterally in or more directions when
compressed. Such materials have been labelled as smart since they
can be made to respond to external stimuli in ways that enhance the
performance of the material. For example, the fact that the
compressed material contracts, and hence increases its density, at
the point where pressure is applied means that they have a higher
potential of resisting impacts when compared to their conventional
counterparts.
The auxetic behaviour is in general due to the inner structure of the
material. A number of such mechanisms have been identified and
studied. However, given that this is a rather novel field of research
many more still need to be analysed. Amongst these are the metachirals that have been proposed and developed by the Malta
Auxetics Group.
This project entails the study of such auxetics materials using
numerical and/or analytical methods. The numerical analysis will
be carried out using ANSYS Mechanical software.
Suitability:
There are no particular prerequisites for this project. The use of
ANSYS Mechanical can be learned through the use of tutorials.
The Malta Auxetics Group has vast experience in its use and can
provide continuous support.
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Project Title:
Investigating the effect of the expansion of the solar magnetic field
on the pitch angle diffusion coefficient
Supervisor:
Dr Pierre-Sandre Farrugia
Abstract:
Solar energetic particles (SEPs) are ions that originate from the sun
and move at a very high speed. They are ejected into space through
event such as flares and coronal mass ejections. These can then be
accelerated in various ways.
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There are various reasons why SEPs are important. The fact that
they are a type of cosmic rays means that they can endanger life in
outer space. On the other hand, SEPs can be used to probe the
interplanetary magnetic field together with the magnetic turbulence
of the solar wind.
As yet, a lot still is unknown about SEPs, particularly in relation to
their acceleration and their transport. This project investigates how
the divergent field lines of the solar magnetic field affect the
transport of such particles by evaluating the pitch angle diffusion
coefficient, a quantity which is related to the diffusion of the
particles in a magnetic field.
The project will involve the numerical solution of the relativistic
equations of motion for particles moving in a magnetic field. From
the trajectories obtained, the pitch angle diffusion coefficient can
be calculated. This can be then corrected for the expansion of the
solar magnetic field using the results of a program obtained in a
previous undergraduate project.
Suitability:
Knowledge of programming languages such as Matlab is required.
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Project Title:
Development of a Dispersion Parameterisation for Atmospheric
Point Emission Sources from Existing Formulations
Supervisor:
Prof Alfred Micallef
Abstract:
A comparative analysis of various dispersion parameterisations,
suitable for point emission sources in unconfined outdoor
environments, will be carried out. The experimental (wind tunnel)
data needed for such analysis is available. Subsequently,
interpolation and other methods will be used to improve on the
parametrisations, possibly leading to a new parameterisation that
performs better than those under investigation.
Suitability:
The project is essentially computational in nature. Inevitably, it
involves theoretical considerations (albeit, simple). It does not
involve any experimental work whatsoever. The project will suit
best someone who has mathematics or statistics as the other subject
option. S/he will be required to do some computer programming.
Nevertheless, the expected computational work should not present
difficulty even for the relatively novice.
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Project Title:
Ab-initio calculation of elastic constants.
Supervisor:
Dr Louis Zammit Mangion
Abstract:
The program Wien2k has been used in past projects to calculate
band structures and energies. By inducing a strain in the crystal
(ie. Changing one or more dimension) and calculating the resulting
energy, it is possible to deduce the corresponding elastic constant
(s). In fact, third party scripts exist to perform this calculation
automatically. The aim of this project is to validate the method
using known materials and then apply it to other materials with
potentially exotic elastic constants.
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Project Title:
Measurement and Analysis of Diurnal Variations of the
Geomagnetic Field
Supervisor:
Dr Louis Zammit Mangion/ Dr Godwin Debono
Abstract:
The project will involve the commissioning and use of a new
proton magnetometer. The instrument will then be used to carry
out a study of the diurnal variations of the Earth’s geomagnetic
field.
Solar radiation incident on Earth ionizes the upper regions of the
atmosphere to generate sun synchronous electrical currents in the
ionosphere at altitudes of 90 to 130 km. These currents generate a
magnetic field of their own that combine with the main magnetic
field generated in the Earth’s core and the crustal magnetic field to
make up the observed geomagnetic field. As the Earth rotates
westward, the electrical currents appear to drift eastward with the
sun and consequently their magnetic field at a given place on Earth
varies with time and has a 24 hour cycle. This variation in the
geomagnetic is known as the Diurnal Variation and can be as
much as 50 nT.
The project involves the continuous measurement of the
geomagnetic field at a location on campus for a period of 1 - 3
months. The Diurnal Variations are then isolated from the main
field and analysed for their spectral characteristics. The student is
also expected to review the topic.
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Project Title:
Synchronisation of quantum systems
Supervisor:
Dr Andre` Xuereb
Abstract:
In 1665, Huygens noticed that two pendulum clocks placed close to
each other tended to synchronise with one another. The study of
synchronisation has become very important in fields as far apart as
electronics and biology, and it is now being imported into quantum
mechanics. Curiously, however, a proper “phase” operator is not
yet known in quantum mechanics, making studies of
synchronisation difficult. This project will study simple
synchronisation problems. It will involve computational work and
could lead to a publication in a peer-reviewed journal.
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Project Title:
A drunkard’s walk on a graph
Supervisor:
Dr Andre` Xuereb
Abstract:
Some time ago [1] we studied what would happen to a phonon (a
quantum of vibration) placed on a harmonic oscillator that is
interacting with many other oscillators. It turns out that the phonon
“melts” and spreads itself as widely as possible in a short time.
This is the opposite behaviour to what is expected in typical
models for conduction, where the phonon propagates from one
point in space to the next. The aim of this project is to consider
more generic interactions, and to understand whether quantum
coherence can be used to speed up or slow down the flow of heat.
This project will involve computational work and could lead to a
publication in a peer-reviewed journal.
http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.112.13360
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Project Title:
Setting up an optical tweezers
Supervisor:
Dr Andre` Xuereb/ Dr Louis Zammit Mangion
Abstract:
The Department of Physics recently upgraded its optics facilities to
include a stateoftheart optics table, an optical tweezers, a spatial
light modulator, and a highpower laser. This project will consist in
setting up Malta’s first optical tweezers experiment [1]. After
constructing this tweezers, you will be able to explore and measure
the Brownian motion of visible particles suspended in a liquid. It is
intended to also explore the viability of using this optical tweezers
to measure geological noise.
https://www.youtube.com/watch?v=ju6wENPtXu8
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Project Title:
Measurement of complex permittivity of tissue mimicking
solutions from 5 GHz to 67 GHz
Supervisor:
Co-supervisor:
Dr Lourdes Farrugia
Prof Charles V Sammut
Abstract:
In this project, the student will use a newly-acquired open-ended
coaxial probe to measure the complex relative permittivity of
sodium chloride from 5 GHz to 67 GHz. The current method to
estimate the measurement uncertainty will be studied and
characterized for this particular measurement system. There is
scope for investigating the behaviour of these physical properties
with temperature and chemical composition. Also, the measured
data together with previously measured data from 500 MHz to 40
GHz will enable comparison between different probes and possibly
establish a wideband frequency model characterising the
permittivity from 10 MHz up to 67 GHz.
This project is a continuation of an undergraduate project started
during the acadmic year 2015/2016 where the dielectric properties
of the same solutions were measured from 100MHz to to 3 GHz,
using a new open-ended coaxial probe covering this frequency
range.
Requirements/Suitability: Laboratory skills are essential, as is an understanding of
vector network analysis (to be acquired as part of the project). A
basic understanding of complex permittivity and the associated
measurement techniques are essential.
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Project Title:
Permittivity measurements for determing the sugar and salt content
in liquids.
Supervisor:
Co-supervisor:
Prof Charles V Sammut
Dr Lourdes Farrugia
Abstract:
Monitoring the glucose levels of food during manufacturing is one
of the routine tests required for quality control. Recently, new
research in the Electromagnetics Laboaroty has revealed that
glucose levels influence mainly the dielectric constant (real part of
permittivity) while salt content change significantly the loss factor
(imaginary part of permittivity). In this project, the student will be
investigating the complex permittivity of different water, sugar and
salt solutions to assess the potential of using permittivity
measurements for determining the glucose and salt content in
liquids.
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This project is a pilot study which can possibly be used in
preparation for a M.Sc. research project, in collaboration with
industry.
Requirements/Suitability: Laboratory skills are essential, as is an understanding of
vector network analysis (to be acquired as part of the project). A
basic understanding of complex permittivity and the associated
measurement techniques are essential.
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Project Title:
Determining the permittivity of a two-layer material.
Supervisor:
Co-supervisor:
Dr Lourdes Farrugia
Prof Alfred Micallef
Abstract:
Measurement of the permittivity of biological materials very often
involves layered structure of biological tissue such as skin and fat.
In this project, the student will be testing an analytical expression
of an open-ended coaxial probe in contact with two-layered
materials. Open-ended coaxial probes are usually used to measure
the reflection coefficient from a homogenous material, which is
then converted to the permittivity using an analytical solution for
the probe. The analytical problem to be solved requires three
calibration parameters which to be determined using experimental
data on a short circuit, deionised water and standard saline
solution. The measurements on the test solution will be determined
and compared to previously published data.
This is a pilot study, which can possibly be used in preparation for
an M.Sc research project.
Requirements/Suitability: It is encouraged that this project is taken by students
interested in both experimental and analytical analysis. A basic
understanding of complex permittivity and the associated
measurement techniques are essential but all the required training
will be given.
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Project Title:
Permittivity measurements using open-ended waveguide.
Supervisor:
Co-supervisor:
Dr Lourdes Farrugia
Prof Alfred Micallef
Abstract:
Conventional waveguide methods for measuring the complex
permittivity of materials require extensive sample preparation,
which can result in sample contamination. In this project, the
student will investigate the use of open-ended waveguides to
determine the complex permittivity of lossy dielectrics. The
reflection coefficient of tissue mimicking solutions, prepared using
glucose, sodium chloride and agar-agar will be measured and then
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the dielectric properties are to be calculated using an optimisation
technique with electromagnetic software(CST).
Requirements/Suitability: It is encouraged that this project is taken by students
interested in both experimental and numerical analysis.The use of
electromagnetic software (eg. CST/HFSS) is required and all the
necessary training will be provided.
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Project Title:
Obtaining variable star light curves with a view to charecterising
equipment feasibility for future time series photometric studies
Supervisor:
Dr Joseph Caruana
Abstract:
This project consists of undertaking CCD photometry of a number
of variable stars, with the aim of assessing the feasibility of the
currently available equipment setup (consisting of a Meade
20.3cm-aperture Schmidt Cassegrain telescope and Meade DSI
PRO III) in undertaking future time series observations. The
student will learn the basics of data management & reduction and
photometric techniques. Due to the nature of the project, the
student is expected to spend considerable time collecting data
during night hours.
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Project Title:
Gravitational Wave detection
Supervisor:
Prof Kristian Zarb Adami
Abstract:
In this project the student will study and simulate how
gravitational waves are created through the merger of black holes
and the ring-down of neutron stars. The student will then go on to
simulate how these gravitational waves would be measured using
existing experiments such as LIGO and VIRGO, but more
importantly will produce experimental forecasts of gravitational
wave detection with LISA.
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Project Title:
Cubesat antenna design for Low-Frequency Radio Astronomy
Supervisor:
Prof Kristian Zarb Adami
Abstract:
In this project, the student will design a low-frequency telescopic
antenna (5-50MHz), designed to fit within a cubesat envelope
(10cm x 10cm x 10cm) in order to be deployed in a Low Earth
Orbit. The student will carry out electromagnetic modelling of the
antenna using HFSS and/or CST and depending on the time
available will be able to produce a prototype of the antenna.
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Project Title:
Space-based Interferometry
Supervisor:
Prof Kristian Zarb Adami
Abstract:
In this project, the student will design and interferometer based on
cubesat technology. The student will work out what the orbital
parameters of the baselines will look like and what fields can be
observed with such an interferometer. Using standard simulation
tools, the student should be able to produce forecasts of Epoch of
Reionisation detection and this project should end with a proposal
for a space-based low-frequency interferometer.
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Project Title:
Expansion Parameters in Alternative Theories of Gravity
Supervisor:
Dr Jackson Said
Co-supervisor:
Prof Kristian Zarb Adami
Abstract:
Looking out in the night sky what one observes is a series of cross
sections through the history of the Universe. This is due to the
finiteness of the speed of light. Thus such observations give a
picture of the expansion history up to early times. Before this
‘barrier’ the cosmos was far too dense for light to move freely.
However the dynamics of this early Universe did leave an imprint
in the so-called cosmic microwave background radiation.
Conversely at late times in the Universe’s history it appears to be
dominated by the exotic dark energy which principally should
dominate over the Universe’s mass-energy budget. This project
will involve looking into the expansion state parameters of the
Universe in alternative theories of gravity with the aim of
reproducing accelerated expansion in late times without the need
of dark energy.
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Project Title:
Stellar tests of Alternative Theories of Gravity
Supervisor:
Dr Jackson Said
Co-supervisor:
Prof Kristian Zarb Adami
Abstract:
Einstein gravity was first proposed in order to incorporate the
special theory of relativity into gravitational systems. The first
tests of his theory were all in the solar system which is the scale at
which it was clear that this theory was already better than
Newton’s theory of gravity. Recently a large number of alternative
theories of gravity have been proposed to account for cosmological
dynamics as well as principle problems within Einstein’s theory of
gravity. Following the four classical tests of general relativity this
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project involves identifying a potential candidate theory of gravity
that behaves well at cosmological scales and testing it at lower
scales within stellar systems. This would mean testing a theory
against light deflection, gravitational time delay, perihelion
precession and gravitational redshift solar system observations.
The aim would be to have a broad scale constraint on its coupling
parameters.
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Project Title:
Dielectric properties of different types of rocks.
Supervisor:
Dr Lourdes Farrugia
Co-supervisor:
Dr Sebastiano D’Amico
Abstract:
Proper interpretation of ground penetrating radar (GPR) images
obtained requires knowledge of the dielectric properties of the
constitutive materials. Dielectric permittivity contrasts underneath
the subsurface causing various reflections in GPR profiles and
eventually provides important information about the underlying
layers. In this project, the student will conduct dielectric
measurements on dry and fully saturated rocks using waveguide
methods. Initially, the rocks will be dried using a loss on drying
method and the correspinding permittivity and permeability of
different types of rocks will be measured. Following that samples
will be fully saturated with water and the dielectric measurements
are measured again. This will result in a range of dielectric
properties required for accurate GPR mappings.
Requirements/Suitability: Laboratory skills are essential and it is encouraged that
the student is highly interested in geosciences.
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