Source:
“Thought experiments made real”, Fernando Martín, Nature Photonics 9, 76–77 (2015)

Read the final article here: http://www.nature.com/nphoton/journal/v9/n2/full/nphoton.2014.325.html or a pre-edited version here.

Institutional web sites (Max Planck Gesellschaft, Universidad Autonoma de Madrid, IMDEA-Nanociencia, or the website dedicated to Higher Education in Madrid) scientific news Agencies (SINC, Madrimasd) and other agencies (europapress), National Newspapers (El País-Materia), Spanish Royal Society of Physics (January 2015 Newsletter), National Radio (Radio5-RNE), various scientific blogs and digital media (La quimica y la ciencia, Noticias de la ciencia, Tendencias21, FisicaHoy, ScienceNewsLine), and scientific networks (COST Action CM1204). Other news articles citing the article can be checked at the publisher’s web site.

23/01/2015 – Open PhD positions are available to work on coupled electron and nuclear dynamics induced by attosecond laser pulses and strong electromagnetic fields on small and mid-size molecules

10/04/2015 – Award decission [Download]

We seek for applicants possessing a bachelor degree in Physics or Chemical Physics plus post-graduate education (MSc), and good programming skills.

Further information can be found here:

• How to apply for the PhD position [Download 2015 application guidelines]
• Application form [Download application form]

Deadline: March, 15th, 2015

21/01/2015 – Open Postdoc positions are available to work on coupled electron and nuclear dynamics induced by attosecond laser pulses and strong electromagnetic fields on small and mid-size molecules .

26/03/2015 – Award decission [Download]

The applicants should possess a PhD in Physics or Chemical Physics and strong and demonstrable background in  atomic, molecular and optical physics, attosecond physics, scattering theory, numerical methods, and programming.

The one year postdoc position should start as soon as possible and, in any case, not later than September 1st, 2015. We have funds to extend the contract for a second year based on performance and upon mutual agreement.

Application procedure: Interested researchers should send a detailed CV, motivation letter and contact information for 2 references (in a single pdf file named as the candidate) to xchem.positions (at) uam.es. Further information may be required.
Recommendation letters could be requested during the selection process. Selected candidates shall be contacted for an interview.

Deadline: February, 15th, 2015

More information  can be found here [postdoc-position-attosec-physics-download]

Electrons moving around an atom nucleus minimize the effect of mutual repulsion by avoiding each other. This results in a “correlated” or “concerted” movement, in which the behavior of a single electron affects the others. So far, this movement had eluded direct experimental observation of scientists.
In the latest issue of the journal Nature, Spanish and German scientists not only presented the first film of correlated motion of the two electrons that make up the helium atom, they also report having controlled the footsteps of his particular ‘dance’.

To do this they used an advanced version of a technique known as Attosecond Transient Absorption Spectroscopy (ATAS), which combines pulses of visible and ultraviolet light to an ultrafast time scale (about a trillionth of a second).

Experiments consisted on the measure of the transparency of a sample of helium with short flashes of ultraviolet light, depending on the time between the flash and a red pulse generated by a titanium-sapphire laser. The ultraviolet pulse leads the atom to an excited state, where both electrons oscillate in concert. Red light pulse weakens or strengthens the ultraviolet light absorption as a function of the relative position of the two electrons and thus, the time between this pulse and the ultraviolet pulse. From variations in ultraviolet absorption, the movement of both electrons can be reconstructed and thereby generate a motion film. The control of this movement was achieved by varying the intensity of the red pulse.

Since most of the bonds holding atoms –from water molecules to DNA- are formed by a two electron pair, this work opens the door to control the properties of chemical bonds and perhaps to produce compounds that cannot be obtained using standard procedures in Chemistry.

These results were obtained with the help of unprecedented quantum mechanical calculations carried out in the frame of XChem project

Figure: Snapshots of correlated motion of the two electrons of helium. 15.3 femtosecond (fs) after starting the clock, the two electrons are near the nucleus (red area near the center of the image) and then move away from it. Color indicates the probability of finding an electron at the position A (vertical axis) and the second of electrons in the position B (horizontal axis) on a line drawn through the atom (along the direction of laser polarization). A femtosecond later, ie 16.3 femtoseconds after starting the clock, electrons have moved back to its original position.

03/11/2014 – We have an open Postdoc position for working on modelling of coupled electron-nuclear dynamics in neutral polyatomic molecules under strong fields.
In particular, the purpose of the work proposed here is to describe theoretically the various vibrational normal modes in such molecules using quantum chemistry methods that can account for the multidimensional character of the vibrational motion in molecular ionization processes. This work will be used to study the attosecond dynamics in ionization of these molecules by using a realistic description of the nuclear motion.

The applicant should possess a PhD in Theoretical/Computational Physics or Chemistry, demonstrable skills in laser physics, imaging and control of molecular electron dynamics, attosecond chemistry, high harmonic spectroscopy and strong fields.

The 1 year postdoc position will start on January 2015.

Application procedure: Interested researchers should send a detailed CV and motivation letter to xchem.positions (at) uam.es. Further information may be required.

Deadline: November, 28th, 2014

Charge migration in molecules precedes structural rearrangements which are the basis of many biological processes. According to the results presented, charge migration from one end of the phenylalanine molecule to the other takes around 3-4 femtoseconds (one femtosecond = 1.000 attoseconds). This is the fastest process ever observed in a biological structure.

The numerical simulations carried out allowed those researchers to identify, unambiguously, that this fast charge migration  is solely due to the electronic motion of the electrons induced by the attosecond pulse, rather than to structural changes. The ability to provoke and observe purely electronic dynamics in biomolecules is crucial for future applications in attosecond science. This charge migration may, as an example, initiate a chemical reaction.

The work, published in Science on October 17th, results from a theoretical/experimental collaboration among researchers involved in the ERC funded projects XCHEM (Universidad Autónoma de Madrid) and ELYCHE (Politecnico di Milano), and from the Ultrafast group at Queen’s University of Belfast, the Theoretical Chemistry group at the Università di Trieste and the Attosecond Physics Group at the Institute of Photonics and Nanotechnologies IFN-CNR of Milano and Padova.

This information has appeared in several institutional websites (UAM, IMDEA-Nanoscience, QUB-Ulfrafast-group, Politecnico de Milano, CNR, IFN-CNR, who also published press releases (UAM, IMDEA-Nanoscience, Polimi and QUB).

Several media have echoed the news, appearing articles in scientific news’ agencies (SINC, Madrimasd), learned societies of chemistry and physics, european research networks (XLIC), digital media (Tendencias Cientificas, Amazing NCyT, BetaWired, Ideal, Solociencia), specialized blogs (Blog in Bio-Science+Technology), newsletters (COST CM1204 Action Newsletter nº3, Boletín campus UAM+CSIC), radio (Radio Exterior-RNE, Radio5-RNE, Radio San Vicente), YouTube (uam-csic channel) and social networks (UCC-UAM, UAM-Gazette.Twitter – SINC, XLIC, etc).

Following the press release published at Queen’s University of Belfast, several English-written online sites have highlighted the importance of the work, “the fastest process ever observed in a biological structure”, “a groundbreaking discovery that has implications for understanding how radiotherapy kills cancer cells” (see PhysOrg, ScienceDaily, Chemistry2011, Nanotechnology News, H202UK)

Highlights:

• Prof. Martin interviewed in the Spanish radio program “Marca España”, on  Nov 3 2014, at Radio Exterior de España. Listen it here.
• Listen to Fernando Martin’s radio interview in a popular science program.
• Video at UAM+CSIC “Campus of Excellence” You Tube channel

Figure: Snapshots of charge distribution on the most abundant conformer of the aminoacid phenylalanine. The charge density can take negative and positive values ​​(yellow) or (purple). The charge migration from one end of the molecule to the other takes no more than three or four femtoseconds.

The work arises from a cooperation among several European researchers (among them the PI’s of two ERC AdG projects, ELYCHE project, with GA nº 227355 and XCHEM project, with GA nº 290853). A clear experimental evidence of ultrafast charge dynamics in the phenylalanine amino acid, after prompt ionization induced by attosecond pulses, has been found. Charge migration shows up as oscillations in the yield of a doubly-charged molecular fragment produced from ionization of a second electron by a probe pulse as a function of its delay time. Two main frequencies were measured: 0.24 PHz (corresponding to a period of 4.2 fs) and 0.36 PHz (period of 2.8 fs), thus confirming the electronic origin of the measured dynamics. Numerical simulations of the temporal evolution of the electronic wave packet created by the attosecond pulse strongly support the interpretation of the experimental data in terms of charge migration.

The ability to initiate and observe purely electronic dynamics in the building blocks of life represents a crucial step forward in attosecond science, which is progressively moving towards the investigation of more and more complex systems and can be considered as a first contribution towards attobiology.

Direct measurement of the ultrafast charge dynamics in an amino acid, initiated by attosecond pulses, represents a crucial benchmark for the extension of attosecond methodology to biology. In the same way in which femtosecond pulses have contributed (and still contribute) to the investigation and understanding of important biological processes, attosecond science offers the possibility to elucidate, on a temporal scale preceding nuclear motion, subtle processes ultimately triggering and determining the response of biomolecules. For instance, how the ultrafast motion of a hole in DNA created by a high-energy particle might initiate cell necrosis or mutation. The results obtained in the case of phenylalanine can be seen as the first experimental confirmation that attosecond pulses and techniques will be essential tools for understanding of dynamical processes on a temporal scale that is relevant for the evolution of crucial microscopic events at the heart of the macroscopic biological response of molecular complexes.

The picture shows XChem researchers directly involved in this work

^[1] Ultrafast electron dynamics in phenylalanine initiated by attosecond pulses
F. Calegari, D. Ayuso, A. Trabattoni, L. Belshaw, S. De Camillis, S. Anumula, F. Frassetto, A. Palacios, P. Decleva, J. B. Greenwood, F. Martín, M. Nisoli
Science 346, 336-339 (2014). DOI:10.1126/science.1254061

05/05/2014 – Open PhD position for working in “Theoretical Modelling of Laser-Induced Ultrafast Phenomena”

30/09/2014 – Award decission [Download]

We seek for applicants possessing a bachelor degree in Physics or Chemistry plus post-graduate education (MSc), and good programming skills.

Further information can be found here:

• General information [Download]
• How to apply for the PhD position [Download application guidelines]
• Application form [Download application form]

Deadline for applications: June 27th, 2014

The activities in relation with UAM-Fujitsu agreement were officially inaugurated past March 17, 2014 with a meeting among representatives from Autonomous University of Madrid, Sciences Faculty, other research centers and universities in Madrid region and Fujitsu.

Shigeru Sasaki, in his lecture “People-centered innovation”, showed the latest developments and research lines being developed by Fujitsu to solve the problems affecting society from the point of view of computing and computer science.
Shigeru Sasaki stressed that the collaboration between UAM and Fujitsu is very important because each country has its own problems and needs their own solutions. This cooperation will lead to significant business opportunities.

This information was published in the University and Sciences Faculty web sites.