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Research perspectives IAPP: COLDBEAMS 7 th October, 2013, Paris Andy McCulloch
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European Research Council: ERC-StG- COLDNANO Marie Curie Industry-Academia Partnerships and Pathways: FP7-PEOPLE-2009-IAPP Orsay Physics Matthieu Viteau Bernard Rasser Pierre Sudraud Laboratoire Aimé Cotton Yoann Bruneau Guyve Khalili Andy McCulloch Isam Manai Mehdi Hamamda Hans Lignier Pierre Pillet Daniel Comparat Justine Houplin Roger Azria Lionel Amiaud Anne Lafosse Institut des sciences molécullaires d’Orsay
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Controlled Chemistry: Nanofunctionalisation of surface molecules The ability to control and orientate chemical reactivity in the condensed phase Many applications, particularly in biotechnology and biosensing Electrons drive bond cleavage, creating highly reactive molecules Local interaction(s) lead to the synthesis of new molecules or bonding with the surface
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Tuning E(e - ) for successive Dissociative Electron Attachement Current source: 5 µA on (1 mm²) (1 A/m²) with 1 eV resolution New source: 10 pA on (10 µm)² (10 5 A/m²) with 1 meV resolution Controlled Chemistry Gold Terminal group spacer Aromatic Alkyl 1eV 6eV Deposited molecular film 9eV
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Controlled chemistry After surface modification, the surface is analysed using HREELS Low current source + serial detection = Long acquisition times (hours) Energy range: 0-2eV, few meV resolution Can we help, not only with functionalisation, but additionally HREELS?
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6eV beam 0-2 eV beam with meV resolution Functionalisation/HREELS
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First steps Produce electrons! Measure beam properties: emittance, etc.
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Energy spread Need to know the energy spread –Spectrometer Can we perform other experiments simultaneously?
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Deterministic single ion source Huge demand for sources of single ions –Large number of applications: Quantum computation, ion implantation, etc. Rydberg atoms provide a simple solution for deterministic source.
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The idea Use fs laser to excite a small volume of atoms (<10 um) Blockade limits excited atom number
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Feedback system Use the electron position to actively correct the ion trajectory (ultimate aberration correction) Only possible to correct ions Position sensitive detector (DLD) Feedback control system
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Ultimate source characterisation Would like to what is the coldest possible electron/ion temperature Accurate electron temperature measurement is difficult, gives little insight into heating mechanism(s) c.f origin of 10 K Ideally, want high resolution images of both electron k and x
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Electron microscope Photoemission electron microscope Measurement of x/k
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The PEEM PEEM provides high resolution (real space) imaging and (transverse) momentum imaging. Combined with TOF spectroscopy –Access to the longitudinal components Can directly measure k and x
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TOF PEEM Using a (3D) MOT as the sample, photoionisation dynamics can be investigated
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Simulations With existing setup, we should be able to obtain high resolution images Upfield emission directly resolvable! Experiment planned Early 2014
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LAC outlook Short term: –Source diagnostics –Single ion source Mid-term –TOF PEEM: Electron source characterisation –Nanofunctionalisation Long-term –Electron/ion feedback –HREELS
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Outlook: other elements? Cold atom electron/ion sources show a lot of promise Cooling molecules can provide additional elements: e.g. CN, BaF … CN for implanting diamond No sources of: B, C, N, O, F, Si, Ga, Ge, As
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Questions? Comments? Thoughts?
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Laser cooling = collimation Rydberg = excitation + Field ionisation Improve focus limit (10µm)x(∆E/E) Huge domain of applications and improvement for: Spectrometers, irradiation, induced chemistry Imaging Sputtering, deposition - + IONIZATION OF COLD ATOMS or MOLECULES To create Bright Ion/Electron beams Example: Implantation of N atoms from Cooling of CN molecules
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