News Archive: 2008 - 2014

01/09/2014: TP Sing and S Bera are visiting the group for a month. we work on a paper on CSL induced random walk.

24/07/2014: Our paper 'Near-field interferometry of a free-falling nanoparticle from a point-like source' has been accepted for publication in the journal Nature Communications.

10/07/2014: Chloe Green, a former group member, has been awarded for the best final year BSc project and the best performance in the final year at Physics Southampton. Many Congratulations!

10/06/2014: All MPhys and BSc students have finished their projects in the group. Many thanks for your help! Over the summer we will have support from four young colleagues: Mark Jenei (cavities), Sam Rios (magnetic trapping), Chris Dawson (cavities), and Ali Farzaneh (gravity collapse). Welcome!

07/06/2014: Hendrik has been promoted to a personal professorial chair with effect of 1st of August 2014.

29/05/2014: Our paper 'Proposal for a Non-interferometric Test of Collapse Models in Optomechanical Systems' [PRL 112, 210404 (2014)] has been published as an Editors' suggestion at Physical Review Letters today.

08/05/2014: Hendrik receives a FPES faculty award for excellence in teaching.

06/05/2014: Our article on 'Proposal for a Non-interferometric Test of Collapse Models in Optomechanical Systems' has been accepted for publication in the journal Physical Review Letters.

28/03/2014: Our article on 'Testing the quantum superposition principle in the frequency domain' has been published in the journal Physical Review A 89, 032127 (2014).

03/02/2014: Eva Kilian on a ERASMUS exchange from Vienna has joined the team and is working with Nathan on the Talbot-Lau Interferometer.

08/11/2013: Our paper on 'Optomechanical interface for probing matter-wave coherence' has been accepted for publication at the NPG journal Scientific Reports.

30/10/2013: Nathan has passed his Phd viva. Congratulations and crack on with the Spin project.

01/10/2013: Five new undergraduate students have started work in our labs. Good luck for your projects.

02/09/2013: Sougato Bose is visiting for discussion on our EPSRC project.

02/09/2013: Stefan Nimmrichter is visiting for a week to work on our concept for a new semi-Talbot interferometer.

01/08/2013: Nathan Cooper has started as the second post-doc in the group. Nathan works on the molecule interferometer and will try to implements some ideas about Stern-Gerlach like manipulation of atoms in this very setup. Welcome.

28/07/2013: Summer project students David Elcock and Harry Morris have started on a graphene project with Paul. Welcome.

03/07/2013: Our review article on 'Experimental methods of molecular matter-wave optics' has been accepted for publication at IOP's review journal Reports on Progress in Physics.

01/07/2013: Three new members of group: Sam Hillman (summer student, undergraduate from Oxford) and David Hempston and Jamie Vovrosh (both PhD) start with today. Sam will work with Xiaxi on the molecule interferometer. David and Jamie join the nanopaticle interferometer team. Let's hope for exciting experimental results soon!

01/07/2013: Finally! Our paper on optical manipulation of fullerenes is on the arxive.

01/06/2013: We thank all MPhys, ERASMUS and project students for their help over the past year. David will continue in the group as a PhD, Ashley will start a MSc in nuclear physics at Birmingham. Good luck to all of them.

13/03/2013: We made it to the University news page and in the public media with our project on quantum interference of nanoparticles.

06/03/2013: Andre Xuereb is visiting us to discuss latest ideas on cavity cooling.

27/02/2013: We are looking for post-doc to join us to work on a Spin-matter wave project together with magnetic resonance expriments from Chemistry.

10/01/2013: We have won a Templeton foundation grant to set up optical tweezer experiments with nanoparticles towards superpostion. The project is for three years in collaboration with Angelo and TP. We are now looking for two more PhD students to join the team.

15/12/2012: Our article on collapse models has been accepted for publication at the prestigeous journal Reviews of Modern Physics.

10/12/2012: Our NJP editorial on Modern Frontiers of Matter-Wave optics and Interferometry has been published.

01/12/2012: James Bateman has joined the team as our first post-doc. Welcome James, there is exciting stuff to do.

01/12/2012: We have won a 4th prize in the 2012 FQXi essay contest with our article on the quantum superposition principle. The article is together with Angelo Bassi and TP Singh.

16/11/2012: Our work on experiments to test the quantum superposition principle has been covered by the FQXi podcast - November issue.

01/11/2012: Mudassar Rashid has joined the team as a PhD student. Muddassar will work on the bead interferometer.

01/10/2012: Jack Morphew has joined the group as a PhD student. Jack will work on trapping and cooling of molecular ions and will be based in Matthias Keller's labs at Brighton.

01/10/2012: Three new MPhys students, David (graphene Hall devices), Ashley (molecule interferometer), and Richard (magnetic lensing) have joined the team to work with us for a year. In addition three Erasmus students, Zahari (magnetic lensing), Jesus (graphene device fabrication), Xiaxi (molecule interferometer) join the team.

30/09/2012: Carola has finished her PhD and defended successfully. Congratulations! Carola will go back home to Berlin. Good luck for the future.

01/08/2012: TP Singh from the TIRF Mumbai is joining us for 6 weeks to work on experimental strategies to test collapse models.

01/07/2012: Two summer students join us to work on graphene devices. Kate is funded by SEPnet and David by an IOP Nuffield grant.

01/06/2012: We have won an EPSRC grant on 'Non-classicalities and Coherent Control at the Nanoscale' together with partners at Imperial College, UCL and Warwick. We are now looking for a post-doctoral researcher to work with us for up to three years.

02/05/2012: We have won a small grant from the Foundational Questions Institute (FQXi) to test an idea on optomechanical detection of molecules.

19/04/2012: Our paper 'Models of Wave-function Collapse, Underlying Theories, and Experimental Tests' has been uploaded to the arXive and submitted to Review of Modern Physics.

02/04/2012: Our paper on 'Phase-space tomography of matter-wave diffraction in the Talbot regime' has been published in the New Journal of Physics

We report on the theoretical investigation of the Wigner distribution function (WDF) reconstruction of the motional quantum state of large molecules in de Broglie interference. de Broglie interference of fullerenes and the like already proves the wavelike behaviour of these heavy particles, while we aim to extract more quantitative information about the superposition quantum state in motion. We simulate the reconstruction of the WDF numerically based on an analytic probability distribution and investigate its properties by the variation of parameters which are relevant for the experiment. Even though the WDF described in the near-field experiment cannot be reconstructed completely, we observe negativity even in the partially reconstructed WDF. We further consider incoherent factors to simulate the experimental situation, such as a finite number of slits, collimation and particle-slit van der Waals interaction. From this we find experimental conditions to reconstruct the WDF from Talbot interference fringes in molecule Talbot-Lau interferometry.

11/01/2012: Press release on our work on the foundations of physics by experimenting with polystyrene spheres. See:

Press release on alpha gallileo ,and youtube video

01/10/2011: PhD students Paul Clark and Alan Forrester have joint us to work on graphene electronics and optomechanical devices, respectively.Three new MPhys students (Mark Treasure, Sam Hendry and Will Hay) have joined the group to work on new molecular beam manipulation techniques. Thanks to all the students who have been working with us over the summer.

01/09/2011: Erasmus student David Grass from Vienna joined the group to work on optically guiding and trapping of nanoparticles in optical fibres. Joe Spenser has started his MPHys (year in experimental physics) project on electro-opto-mechanical detection of particles.

20/06/2011: Three students have started their summer projects in the group. Marta is joining Carola on the molecule interferometer, George is working on graphene MEMS mass detectors (funded by a EPSRC bursay), and Claire is working on an idea to select chiral molecules (funded by Physics, Soton).

03/06/2011: Our paper on 'Coherent control of the motion of complex molecules and the coupling to internal state dynamics' has been accepted by Faraday Discussions for publication.

We discuss coherent control of the centre of mass motion of complex molecules by de Broglie interferometry. We describe an experiment to couple the dynamics of internal state population of complex molecules to their centre of mass motion. We discuss how this can be used to probe state population and transition, especially the photo-switching of flourinated di-azobenzene molecules between their cis- and trans-configuration. We propose an experiment to photo-isomerise complex di-azobenzene molecules in the gas-phase, including the selective detection of molecules in different conformations. In addition we discuss possible ways of optimising the conformation detection through cooling, and optical techniques.

Faraday Discuss., Advance Article, DOI: 10.1039/C1FD00066G (2011)

25/05/2011: We have won a small grant from the Metamaterials Programme grant Innovation Fund to pursuit an idea on 'Negative-index media for de Broglie optics of complex molecules'. We will start to test this idea soon.

04/05/2011: Mag Wolfgang Trasischker is joining the group to work on de Broglie interference experiments with polystyrene spheres.

20-23/02/2011: Dr Andreas Jacob from the Max-Planck Insitute for the physics of complex systems is visiting us to discuss theory on Talbot Lau interferometry and the effects of Casimir-Polder interactions. The visit is financed by the ESF CASIMIR network. On 22/02/2011 Dr Stefan Buhmann from Imperial College is joining us to teach us on the fundamentals of dispersion forces and how to calculate them.

18/01/2011: We have won a large grant from the Foundational Questions Institute (FQXi) to perform de Broglie interference experiments with polystyrene spheres.

15/01/2011: We got a new large lab for our matter-wave interference experiments with polystyrene spheres. The lab is now under reconstruction ...

01/11/2010: We have won a fs-laser form the EPSRC/STFC laser loan pool to use for 6 month together with Otto Muskens. Paul performs experiments on the optical manipulation (lensing, guiding, deceleration) of porphyrin molecular beams.

01/10/2010: Three MPhys students join the group: Michelle Ross, Liam Boodhoo, and Paul Clark. They will work on graphene projects and use nanofabrication facilities at physics and the new Mountbatten centre. Fingers crossed that we will have nice graphene samples soon to start the science projects.

20/09/2010: Our paper 'A helical velocity selector for continuous molecular beams' has been accepted for publication at Review of Scientific instruments.

We report on a modern realization of the classic helical velocity selector for gas phase particle beams. The device operates stably under high vacuum conditions at rotational frequencies limited only by commercial DC motor capabilities. Tuning the rotational frequency allows to selectively scan over a broad velocity band. The width of the selected velocity distributions at full-widthhalf-maximum is as narrow as a few percent of the selected mean velocity and independent of the
rotational speed of the selector. The selector generates low vibrational noise amplitudes comparable to mechanically damped state-of-the-art turbo-molecular pumps and is therefore compatible with vibration sensitive experiments like molecule interferometry.

Review of Scientific instruments 81, 106107 (2010)

20/06/2010: Paul Venn will start a PhD in our group in late summer. Paul (on a SEPNet scholarship) will join Carola on molecule interference.

15/06/2010: Joseph Rushton and Lee Patterson finish their MPhys projects. Jo wins the best project award in Physics 2010 at Southampton. Congratulations!

01/06/2010: Students Joe Spencer and Jamie Collier join the group for summer projects on molecule interference and graphene device fabrication

08/03/2010: Publication of our paper on 'Influence of conformational molecular dynamics on matter wave interferometry' in Phys Rev A (R).

31/12/2009: Publication and PRL Editors suggestion of our paper on 'Wave and Particle in Molecular Interference Lithography'.

The wave-particle duality of massive objects is a cornerstone of quantum physics and a key property of many modern tools such as electron microscopy, neutron diffraction or atom interferometry. Here we report on the first experimental demonstration of quantum interference lithography with complex molecules. Molecular matter-wave interference patterns are deposited onto a reconstructed Si(111) 7x7 surface and imaged using scanning tunneling microscopy. Thereby both the particle and the quantum wave character of the molecules can be visualized in one and the same image. This new approach to nanolithography therefore also represents a sensitive new detection scheme for quantum interference experiments.

Phys. Rev. Lett. 103, 263601 (2009)

13/10/2009: Paper publishd on 'A superconducting NbN detector for neutral nanoparticles'

We present a proof-of-principle study of superconducting single photon detectors(SSPD) for the detection of individual neutral molecules/nanoparticles at low energies. The new detector is applied to characterize a laser desorption source for biomolecules and allows retrieval of the arrival time distribution of a pulsed molecular beam containing the amino acid tryptophan, the polypeptide gramicidin as well as insulin, myoglobin and hemoglobin. We discuss the experimental evidence that the detector is actually sensitive to isolated neutral particles.

Nanotechnology 20, 455501 (2009)

1/10/2009: MPhys students Joseph Rushton and Lee Patterson join the group

15/09/2009: Paper published on 'UV and VUV Ionization of Organic Molecules, Clusters, and Complexes'

The generation of organic particle beams is studied in combination with photoionization using UV radiation at 266 nm and vacuum ultraviolet (VUV) light at 157 nm. Single-photon ionization with pulsed VUV light turns out to be sensitive enough to detect various large neutral biomolecular complexes ranging from metal−amino acid complexes to nucleotide clusters and aggregates of polypeptides. Different biomolecular clusters are shown to exhibit rather specific binding characteristics with regard to the various metals that are codesorbed in the source. We also find that the ion signal of gramicidin can be increased by a factor of 15 when the photon energy is increased from 4.66 to 7.9 eV.

J. Phys. Chem. A 113, 9952 (2009).

20/07/2009: Undergarduate students Charlotte Davis and Alice McKenna join our group for the summer to work on a graphene project

06/07/2009: Undergraduate students Jamie Collier and Paul Venn join our group for the summer to work on molecular beams and buffer gas cooling

27/04/2009: Paper published on 'Theory and experimental verification of Kapitza Dirac Talbot Lau interferometry'

Kapitza Dirac Talbot Lau interferometry (KDTLI) has recently been established for demonstrating the quantum wave nature of large molecules. A phase space treatment permits us to derive closed equations for the near-field interference pattern, as well as for the moire type pattern that would arise if the molecules were to be treated as classical particles. The model provides a simple and elegant way to account for the molecular phase shifts related to the optical dipole potential as well as for the incoherent effect of photon absorption at the second grating. We present experimental results for different molecular masses, polarizabilities and absorption cross sections using fullerenes and fluorofullerenes and discuss the alignment requirements. Our results with C60 and C70, C60F36 and C60F48 verify the theoretical description to a high degree of precision.

New J Phys 11, 0403032 (2009)

01/02/2009: International Patent published on 'Devices for and methods of handling nanowires'

An apparatus for handling nanowires, the apparatus comprising an electromagnetic radiation source adapted for irradiating a body comprising nanowires with an electromagnetic radiation beam to thereby evaporate the body so that the nanowires are released from the body, and a fluidic stream generation unit adapted for generating a fluidic stream for carrying along the released nanowires with the fluidic stream. An apparatus and a method for sorting particles of high polarizability anisotropy - such as for instance carbon nanotubes - in the gas phase according to this property, using a three-grating deflectometer. A method for switching molecular beams of high polarizability using a three-grating deflectometer.

European Patent Office: WO2009000285(A1)


09/12/2008: Paper published on 'Absolute absorption spectroscopy based on molecule interferometry'

We propose a method to measure the absolute photon absorption cross section of neutral molecules in a molecular beam. It is independent of our knowledge of the particle beam density, nor does it rely on photoinduced fragmentation or ionization. The method is based on resolving the recoil resulting from photon absorption by means of near-field matter-wave interference, and it thus applies even to very dilute beams with low optical densities. Our discussion includes the possibility of internal state conversion as well as fluorescence. We assess the influence of various experimental uncertainties and show that the measurement of absolute absorption cross sections is conceivable with high precision and using existing technologies.

Phys. Rev. A 78, 063607 (2008)

01/10/2008: Start in Southampton: new game, new stage, new band!