member-academic-staff
Gil Alexandrowicz

Gil Alexandrowicz

Associate Professor
+972-4-8295963
+972-4-8295703
352
Structure and ultra fast dynamics on surfaces, helium atom scattering, nano-scale friction on surfaces & magnetically manipulated atomic and molecular beams.

The common theme to my research activities is using magnetically manipulated atomic and molecular beams in order to study surface structure and dynamics. Currently the group is involved in several projects related to this theme.4

One unique tool we use is a helium-3 spin echo (HSE) spectrometer. In this apparatus a thermal atomic-beam of helium-3 atoms is scattered from the surface we wish to study. Motion on the surface, is detected by magnetically manipulating the atomic beam. The ultra-high energy resolution of this technique (micro electron volts) leads to the ability to measure atomic-scale surface dynamics, on a unique time range- pico to nano seconds, a range which is not accessible using any other conventional method.

Since the way an atom or a molecule moves on a surface reflects all the interactions it experiences, atomic-scale motion measurements supply a rare opportunity to study the inter-molecular and molecule-surface interactions as well as the energy exchange rate between the moving species and the surface below. Using the HSE apparatus in Cambridge and more recently the new HSE we built at the Technion, we have studied a wide range of adsorbate systems. Examples include studying the adsorption energy landscape of CO on a copper surface[Phys. Rev. Lett. 93, 156103 (2004)], revealing the complex many-body interactions in CO/Pt(111)[ JACS, 130, 6789(2008)], studying the 3D correlated motion of sodium atoms on a copper surface[Phys. Rev. Lett. 97, 156103 (2006)], determining the nano-scale friction and potential energy surface of propane on a platinum surface[New Journal of Physics, 10, 125026(2008)] and studying the effect atomic steps have on the correlated motion of an adsorbed particle[Journal of Physical Chemistry  Letters., 2015, 6, 4165 (2015). The HSE instrument is also a state of the art diffractometer which can be used to determine structure of surface layers, for example we used the apparatus to reveal the surprisingly ordered structure of an ice layer on a gold surface[Journal of Physical Chemistry – C, 117, 23657 (2013)].

A second different project we are pursuing is the development of spin-separation methods for molecular beams and the application of these beams to perform hyper-sensitive surface studies. Separating the nuclear-spin isomers of molecules is a field which has attracted considerable interest over the years due its importance in a wide variety of fields and applications. Examples include enhancing the sensitivity of nuclear magnetic resonance measurements as well as the estimation of inter-stellar temperatures in the field of astrophysics.

We demonstrated that a molecular beam of water can be focused to obtain a high purity beam of ortho-water, work which was published in Science magazine [Science, 331, 319(2011)]. We have since shown that the ortho-water molecules we produce can be stored for long periods inside a cold gas matrix [Physical Review A, 86, 062710 (2012)]. One major research project we are now pursuing is to utilize our spin-separation apparatus in order to grow a hyper-polarized thin layer of water on a surface and enable the first measurements of pre-polarized proton NMR. If this activity is successful, the contribution of the NMR technique to the field of surface science will be dramatically enhanced.

Ultra-fast surface dynamics

Post doc: College Research Fellow, Gonville and Caius College, University of Cambridge, 2005-2008

Ph.D: Physics, Cavendish Laboratory, University of Cambridge 2005

Awards

2015 ICS prize for outstanding young scientist
2012 Krill Prize – Wolf fundation
2011 Henry Taub Award
2009 Landau Fellow
2009 Alon Fellowship
2005: ECOSS Young Researcher Prize – ECOSS-23, Berlin.
2005: Research Fellowship Competition – Gonville and Caius College, Cambridge University.
2002: Overseas Research Awards Scheme
2001: Gates Cambridge Scholarship

 

  1. Alexandrowicz et al., Physical Review Letters 93, 156103 (2004).
  2. Jardine et al. Science 304, 1790(2004).
  3. Alexandrowicz et al., Physical Review Letters, 97, 156103 (2006).
  4. Alexandrowicz et al., Journal of American Chemical Society, 130, 6789 (2008).
  5. Jardine et al., New Journal of Physics, 10, 125026 (2008).
  6. Kole at al. Journal of Physics: Condensed matter, 22, 304018 (2010).
  7. Avidor et al., Journal of Physical Chemistry A., 115, 7205 (2011).
  8. Kravchuk et al., Science, 331, 319 (2011).
  9. Kole et al. Journal of Physics: Condensed Matter, 24, 104016, (2012).
  10. Turgeon et al. Physical Review A 86, 062710 (2012).
  11. Corem et al. Journal of Physical Chemistry – C, 117, 23657 (2013).
  12. Diamant et al. Journal of Physics: Condensed Matter, 27, 125008 (2015).
  13. O. Godsi et al. Journal of Physical Chemistry Letters., 2015, 6, 4165 (2015).

 

Name Email Room Phone
Dr. Oded Godsi chgodsi@technion.ac.il 307 5568
Dr. Ilya Litvin  ilyali@technion.ac.il 307 5568
Gefen Corem gefenc@technion.ac.il 307 5568
Michael Horvat  hmichal@technion.ac.il 307 5568
 Yossi Alkoby yosia@campus.technion.ac.il 307 5568