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注册: 2015-10-29

[交流] Université Paris-Sud PhD position: femtosecond laser

导师：
Bertrand POUMELLEC  bertrand.poumellec@u-psud.fr
Valérie ALEZRA    valerie.alezra@u-psud.fr;

导师的学术水平高，认真负责。极力推荐。税前每月工资2025欧。
申请截止日期5月8号。

研究课题（https://www.adum.fr/as/ed/voirproposition.pl?site=PSaclay&matricule_prop=15625#version）：

Demonstration of femtosecond laser chirality control during crystallization of organic compounds or multiphotonic photochemical reactions

Keywords
femtosecond laser, laser chemistry, organic chemistry, laser nucleation control, laser chirality control

Profile and skills required
The candidate must have a profile 'Optics and Materials Science' with knowledge in Physical Chemistry. Must be able to handle a high-tech laser and understand the optical settings. To characterize the structural changes photoinduced glass across nm, we use a series of spectroscopic methods such as Raman, absorption or luminescence, X-ray diffraction on powder or single crystal, etc .... For interpretations, we need concepts in solid state physics and physical chemistry and some basis on chemistry in solution. Knowledge of English is of course also necessary.

Project description
The main objective of this project is to show that organic molecules contained in a solid or in a liquid can be aligned efficiently with a powerful focused fs laser in controlling the light polarization. We have already shown in the group that orientation of optical non-linear nanocrystals in a glass matrix can be achieved (a breakthrough in the field).
Here, we want to control the molecular arrangement and the molecular type of the products (Rectus or Sinister enantiomers) in three main directions: 1-during the crystallization of a supersaturated solution, 2-in the crystal by changing the enantiomer type of the molecule, 3-in particular photo-chemical reaction.
The interest of this research is the pharmaceutical industry since the type of final product (polymorphism, enantiomorphism) determines the bioactivity of the drug. A chiral separation of the bioactive enantiomer during the API preparation is a key point. There are here a clear economical issues to simplify or increase the elaboration efficiency.
However, several challenges have to be faced.
- In methodology, we want to use the laser polarization, an idea already well known in gases but not demonstrated that can be efficient with the peculiar properties of the fs laser in condensed matter.
- Conceptually, as we think that reaction mechanisms are different at high light intensity, we want to prove that new routes are available for molecular alignment1.
- Technologically, we have to find the domain of laser parameters (numerous) in which the molecules are “softly” reorganized and not destructed.

References
1. Poumellec, B.; Lancry, M.; Desmarchelier, R.; Herve, E.; Bourguignon, B., Parity violation in chiral structure creation under femtosecond laser irradiation in silica glass? Light-Science & Applications 2016, 5.
2. Cao, J.; Poumellec, B.; Brisset, F.; Helbert, A.-L.; Lancry, M., Tunable angular-dependent second-harmonic generation in glass by controlling femtosecond laser polarization. J. Opt. Soc. Am. B 2016, 33 (4), 741-747.
3. Clair, B.; Ikni, A.; Li, W. J.; Scouflaire, P.; Quemener, V.; Spasojevic-de Bire, A., A new experimental setup for high-throughput controlled non-photochemical laser-induced nucleation: application to glycine crystallization. Journal of Applied Crystallography 2014, 47, 1252-1260.
4. Ikni, A.; Clair, B.; Scouflaire, P.; Veesler, S.; Gillet, J. M.; El Hassan, N.; Dumas, F.; Spasojevic-de Bire, A., Experimental Demonstration of the Carbamazepine Crystallization from Non-photochemical Laser-Induced Nucleation in Acetonitrile and Methanol. Crystal Growth & Design 2014, 14 (7), 3286-3299.
5. Li, W. J.; Ikni, A.; Scouflaire, P.; Shi, X. X.; El Hassan, N.; Gemeiner, P.; Gillet, J. M.; Spasojevic-de Bire, A., Non-Photochemical Laser-Induced Nucleation of Sulfathiazole in a Water/Ethanol Mixture. Crystal Growth & Design 2016, 16 (5), 2514-2526.
6. Jacob, J. A.; Sorgues, S.; Dazzi, A.; Mostafavi, M.; Belloni, J., Homogeneous Nucleation-Growth Dynamics Induced by Single Laser Pulse in Supersaturated Solutions. Crystal Growth & Design 2012, 12 (12), 5980-5985.
7. Liao, Y.; Génot, V.; Audibert, J.-F.; Pansu, R. B., In situ kinetics study of the formation of organic nanoparticles by fluorescence lifetime imaging microscopy (FLIM) along a microfluidic device. Microfluidics and Nanofluidics 2016, 20 (4), 59.
8. Philippot, C.; Dubois, F.; Bacia, M.; Djurado, E.; Ibanez, A., Fluorescent organic nanocrystal confined in sol–gel matrix for bio-imaging. Journal of Sol-Gel Science and Technology 2011, 57 (3), 253-257.
9. Dubuisson, E.; Marty, L.; Cattoen, X.; Pansu, R.; Szunerits, S.; Ibanez, A., Rhodamine B nanocrystals: elaborations, characterizations and functionalizations for biosensing applications. Journal of Sol-Gel Science and Technology 2014, 72 (1), 179-188.
10. Mai, T. T.; Branca, M.; Gori, D.; Guillot, R.; Kouklovsky, C.; Alezra, V., Absolute Asymmetric Synthesis of Tertiary α-Amino Acids. Angewandte Chemie International Edition 2012, 51 (20), 4981-4984.
11. Mai, e. a., 'Frozen chirality of tertiary aromatic amides: access to enantioenriched tertiary alpha-amino acid or amino-alcohol without any chiral reagent ',. Chem. Eur. J. 2017
12. Yang, C.; Inoue, Y., Supramolecular photochirogenesis. Chemical Society Reviews 2014, 43 (12), 4123-4143.
13. Brimioulle, R.; Lenhart, D.; Maturi, M. M.; Bach, T., Enantioselective Catalysis of Photochemical Reactions. Angewandte Chemie International Edition 2015, 54 (13), 3872-3890.
14. Kassir, A. F.; Ragab, S. S.; Nguyen, T. A. M.; Charnay-Pouget, F.; Guillot, R.; Scherrmann, M.-C.; Boddaert, T.; Aitken, D. J., Synthetic Access to All Four Stereoisomers of Oxetin. The Journal of Organic Chemistry 2016, 81 (20), 9983-9991.
15. Hernvann, F.; Rasore, G.; Declerck, V.; Aitken, D. J., Stereoselective intermolecular [2 + 2]-photocycloaddition reactions of maleic anhydride: stereocontrolled and regiocontrolled access to 1,2,3-trifunctionalized cyclobutanes. Organic & Biomolecular Chemistry 2014, 12 (41), 8212-8222.

需要提交的材料：

1) doctoral project (5 pages maximum) 未来博士课题的研究计划
2) CV
3) motivation letter
4) recommandation letters

有任何问题和上述材料发送到：
Bertrand POUMELLEC  bertrand.poumellec@u-psud.fr
Valérie ALEZRA    valerie.alezra@u-psud.fr;

Details are included below.

Details for the applications:
The following information will be strictly identical to those contained in the Project submitted by the thesis supervisor and selected by the priority board of the IDI.

The priority axis of the 2017 IDI (for us it is science and Innovation)
The full and up-to-date personal information of the thesis supervisor and where applicable, the co-Director or other people of the coaching team,
the title of the project, in French and English
The summary of the project (15 lines) in French and English, and the key words, emphasizing which gives an interdisciplinary character to this project,
the type of financing requested (at 100% funding), the research unit (s) supporting the project, (verify that it belongs to the perimeter of IDEX in the list provided in the appendix),
The doctoral school of attachment (for us Ed 2MIB),
The registration operator establishment (for us UPSud),

The following information may be eventually adapted and refined with the candidate Retained By the supervisors of theses, after exchanges between the Director of Thesis and different Candidates:

The institution that will be the employer of the doctoral student (for us UPSud),
The detailed topic of the proposed interdisciplinary research project as a doctor project (Five pages maximum) In particular: the scientific and societal context of the project, The expected impact, the research program envisaged, the equipment to be used, the planned financing arrangements, expected in terms of future developments in Research and applications, specifying what gives an original and interdisciplinary character to the project.
The cover letter of the candidate shall explain (two pages maximum) his motivation for the proposed subject, as well as the skills acquired and to be acquired within the framework of the thesis, and the perspectives career opportunities.
The CV of the candidate will necessarily include the available master notes (M1 and M2) or the last diploma giving the degree of master or of the last diploma, obtained or in preparation
Will mention the experience of research Of the candidate (Referent names Accessible). In the event of non availability of master Application, the candidate Must indicate in his file the date on which these notes will be available and send these notes as soon as possible after that date.

Notices or Letters of recommendation
The word notice of the Director of the reasoned opinion of the supervisor of the thesis are mandatory.
Notice mentions the link with the IDEX’s scientific strategy and in particular the priority axis of IDI 2017
Where appropriate, the reasoned opinion of a coordinator of projects of IDEX will support the file.
Where appropriate, can also be joined letters of reference or of tutors testifying  the way in which would Activities past research experi-candidate (Previous research internship).

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