AtMol Research Seminar Archive
Index Current Seminars

Epiphany Term 2013

Date Speaker Institution
The Tumbleweed: An approach to creating designed protein motion
Wed 16 Jan 2013 Dr Beth Bromley Durham University

Biomolecular motors have inspired the design and construction of artificial nanoscale motors and machines based on nucleic acids, small molecules, and inorganic nanostructures. However, the high degree of sophistication and efficiency of biomolecular motors, as well as their specific biological function derives from the complexity afforded by protein building blocks. Here, we discuss a novel bottom-up approach to understanding biological motors by considering the construction of synthetic protein motors. Specifically, we present a design for a synthetic protein motor that moves along a linear track, dubbed the "Tumbleweed."

Light transport in media with strong dipole-dipole interactions.
Wed 23 Jan 2013 Prof. Charles Adams Durham University

Strong dipole-dipole interactions can dramatically modify the optical response of a medium and give rise to non-trivial propagation effects such as the conversion of classical light into quantum light or resonant energy transfer (photon hopping) as in photosynthesis. In this talk we consider the interaction of light with a one, two and many dipoles and subsequently discuss recent experiments on light propagation in atomic systems where the dipole-dipole interaction is manifest.

Multi-photon and sub-Doppler laser-cooling of "difficult" atomic species
Wed 30 Jan 2013 Dr Saijun Wu Swansea University

Laser cooling relies on velocity selective optical forces to increase a gaseous atomic sample's phase space density, thereby cooling the atoms. In nearly all laser cooling schemes, both the velocity selectivity and the radiation forces are accomplished using optical transitions between atomic ground and excited states. There are, however, a class of atomic species, such as (anti)hydrogen, that are hard to be laser-cooled due to unavailability of radiation source at the required wavelengths (e.g., deep ultraviolet). In this talk I will review some of recent work on laser cooling using multi-photon and excited state transitions, which may provide an alternative route toward efficient cooling of these atomic species. The sub-Doppler cooling effect observed in this experiment will also be discussed together with recent progress on sub-Doppler cooling of K40, an important fermionic alkaline species for degenerate quantum gas researches.

Atmospheric-pressure plasma jets for biomedical and industrial applications
Wed 6 Feb 2013 Dr Erik Wagenaars University of York

Novel plasma jets can operate in open air, at room temperature and have highly selective plasma chemistry. This combination of characteristics makes them ideal for many applications, both in healthcare and industrial manufacturing, ranging from wound healing, to improving wettability of plastics, to sterilisation of already packaged food. For all these applications it is vital to have an accurate control and understanding of the plasma jet to guarantee the effectiveness and safety of these devices. A challenging aim since these plasmas are extremely difficult to diagnose because of their small size, highly transient nature, and most importantly the complex interactions and transport of the different plasma particles and surrounding air. Our work aims at developing suitable diagnostic techniques, e.g. (laser) spectroscopy and time-resolved imaging, capable of directly measuring plasma properties. The knowledge gained from these measurements in combination with modelling efforts will enable us to improve these jets for specific applications.

Cold Free-radical Molecules: OH, NH, and CH
Wed 13 Feb 2013 Dr Heather Lewandowski JILA

Studying interactions and reactions between cold molecules can elucidate the detailed role of quantum mechanics in molecular collisions. In particular, reactions including free-radical species are important in combustion, atmospheric, and interstellar chemistry. There has been considerable work to create samples of cold chemically important molecules, but creating samples with sufficient densities to precisely study interactions is still an ongoing challenge. These challenges are even greater with free-radical species, which must be created in situ. I will discuss our ongoing work to create, trap, and detect with increased efficiency several of the fundamental free radicals.

Journal Club Talk — Airborne Transmission of Influenza A/H5N1 Virus Between Ferrets
Wed 20 Feb 2013 in Ph8 Mr Daniel Sadler Durham University

Highly pathogenic avian influenza A/H5N1 has been identified as having the potential to be a future pandemic strain. For this potential to be realised the virus must first become able to readily spread between mammalian hosts, a trait which it has until now lacked. This talk will present recent work by Fouchier et al. conducted to explore the likelihood of H5N1 acquiring this ability through natural mutation.

Journal Club Talk — A guide to simple SQUID recipes
Wed 27 Feb 2013 Mr Manfred Yu Durham University

Quantum simulation of complex quantum systems has been a rich subject of research in the past decade. This has been realized in various experiments, for instance, ultracold atoms in optical lattices and measurement-based linear optics. Recently, there is a new implementation of quantum simulators using superconducting circuits, namely superconducting quantum interference devices (SQUID). Due to the flexibility of fabrication and the suitability for non-equilibrium simulation, such devices have produced promising results in many areas ranging from cavity QED, quantum computing, to coupling with Rydberg atoms and BEC. In this talk I will discuss the superconducting circuits, the manipulation of artificial atoms, and the quantum simulation of cavity QED experiments.

Journal Club Talk — Cold Chemistry: From Star Dust to Quantum Effects in Chemical Reactions
Wed 6 Mar 2013 Ms Arin Mizouri Durham University

Cold chemistry is an emerging field with many theoretical predictions and very few experiments. The primary focus so far has been on chemical processes at temperatures of 10-100 K, relevant to fundamental questions of composition and routes to complex molecule formation in the dense interstellar clouds or atmospheres of exoplanets. Theoretical quantum chemistry suggests that at low-enough collision energies, where reactants’ de Broglie wavelength approaches the characteristic interaction length scale, quantum effects, such as tunneling though reaction or centrifugal barriers, will dominate the reaction dynamics. These effects occur at temperatures of ~1 K and below. I will discuss a recent experiment where resonances in penning ionization reactions were detected at sub-kelvin temperatures in merged beams.

Talk Title TBA
Wed 13 Mar 2013 Dr Lev Khaykovich Bar-Ilan University

Abstract TBA