PhD Studentship: Terahertz Applications Group Dynamics of hydrogen-bonded glasses at terahertz frequencies

Due to funding regulations, this studentship is only available to students who meet the eligibility criteria of the UK Research Councils: http://www.admin.cam.ac.uk/students/studentregistry/fees/funding/councils/eligibility.html

A 3-year, fully funded PhD studentship is available in the Terahertz Applications Group working with Dr Axel Zeitler on the understanding of the fundamental relaxation and vibrational processes occurring in amorphous solids (glasses) with a particular emphasis on, but not restricted to, thermal history.

We currently develop terahertz spectroscopy as a novel technique in characterisation of glasses and supercooled liquids. Terahertz spectroscopy (using electromagnetic radiation of frequencies around 1 THz = 10¹² Hz) is able to probe the intermolecular interaction of hydrogen-bonded materials as its photon energy (meV) covers that of the hydrogen bond. The terahertz time-domain spectroscopy (THz-TDS) technique that we have developed in our laboratory can be used to study the dielectric losses at frequencies that are not experimentally accessible with other techniques. Terahertz spectra of glasses contain several universal features. The most obvious is the microscopic peak, a feature that is yet not fully understood. Commonly it is thought to originate from phonon-like features that are still present in amorphous solids. As the samples are heated above the glass transition the absorption level of terahertz radiation increases due to an increase in molecular mobility. The project will examine the effect of cooling rate, annealing, and possibly pressure, on both these features, i.e. the microscopic peak and the change in the molecular mobility around the glass transition temperature.

We will also try to relate the observations to the long-term stability of the glasses and their crystallisation. Understanding the long-term stability of glasses is a difficult problem from a practical point of view and would have a direct and immediate effect on a broad range of industrial applications, including the food, cosmetic and pharmaceutical industries.

In addition to the experimental work using THz-TDS in our laboratory there will be opportunities to explore these complex physical phenomena by means of computational modelling and run complementary experimental work using the far-infrared beamline at the Diamond synchrotron as well as potential experiments using a terahertz free electron laser.

The terahertz applications group in the Department of Chemical Engineering and Biotechnology runs a successful research programme in terahertz technology (www.ceb.cam.ac.uk/thz.php) and is well networked with leading groups in solid state pharmaceutical research (www.pssrc.org).

Applicants should have a First Class (or a high 2:1) degree in a relevant discipline such as physics, chemical engineering, chemistry, engineering or pharmacy.

To apply for the studentship:

1.  Please take the eligibility test at: http://www.admin.cam.ac.uk/students/studentregistry/fees/funding/councils/eligibility.html  If you meet the criteria, please proceed with step 2. If you do not meet the criteria, we regret that we cannot consider you for the studentship.

2.  Please put the Vacancy Reference number and title in the subject line of your email: (NQ02183) UK/EU Studentship: Terahertz Applications Group

3.  Please send a detailed curriculum vitae (to include numerical details of grades obtained in relevant examinations) to: recruitment@cheng.cam.ac.uk before 17:00 on Tuesday 31 December 2013.

Informal enquires can be directed directly at Dr Axel Zeitler (jaz22@cam.ac.uk); please do not send applications to Dr Zeitler’s email address.