INSTITUTE for LASER, PLASMA and RADIATION PHYSICS
LABORATORY of SOLID-STATE QUANTUM ELECTRONICS
TITLU: GENERAREA DE UNDE THz ULTRAINTENSE IN PLASMA CREATA IN AER CU AJUTORUL FASCICULULUI LASER DE MARE INTENSITATE
TITLE: Ultraintense THz wave generated in air-plasma by short-pulse high-intensity laser beam
Octombrie 2011 - Decembrie 2016
PROJECT DURATION: October 2011 - December 2016
CONDUCATOR PROIECT: Institutul National de Cercetare-Dezvoltare pentru Fizica Laserilor, Plasmei si Radiatiei, Magurele, Bucuresti, Romania
PROJECT LEADER: National Institute for Laser, Plasma and Radiation Physics, Magurele, Bucharest, Romania
Contract value: 1.500.000 lei
Valoare contract: 1.500.000 lei
The research team: DASCALU Traian, PhD
Echipa de cercetare: PAVEL Nicolaie, PhD
DINCA Mihai, PhD
URSESCU Daniel, PhD
GRIGORE Oana Valeria, PhD student
SALAMU Gabriela, PhD student
BRANDUS Catalina Alice, PhD student
The use of ultrashort THz pulses is facilitating terahertz spectroscopy of a wide range of physical, chemical, and biological samples, and enables time-resolved measuremets in which the terahertz is used to probe dynamical responses to an optical excitation pulse. Recently the development of intense ultrafast lasers have allowed table top sources of ultrafast THz pulses approaching the mJ level in energy opening a new way for ultrashort nonlinear THz spectroscopy and large protein conformational changes. This high energy THz pulses with large broad band have been obtained by laser filamentation in a gas. When a laser pulse is focused in a gas, due to balance among natural diffraction, plasma defocusing and Kerr self-focusing, laser pulses carries out periodic defocusing and self-focusing, and can propagate long distance. There are several models explaining THz generation in plasma filaments: dipole like current generated by the laser ponderomotive force, or four wave-mixing model in two-color ultrashort laser filments in air etc.
October - December 2011. Theoretical studies on intense ultrashort
broadband THz pulse
emission from gaseous media excited by focused single and 2-color
Stage 2. January - December 2012. Implementation of ultrashort intense THz sources by single color filament. Enhancement of THz high field strength by 2-color filamentation and multifilamentation.
Stage 3. January - December 2013. Development and optimization of intense ultrashort broadband THz pulse emission from gaseous media excited by focused single and 2-color femtoseconds laser pulses.
Stage 4. January - December 2014. Tailoring the shape and pulse duration of THz radiation through the multifilamentation characteristics.
The main objective of this project will be to carry on research about THz wave air plasma generated by high intensity laser beam, as a THz source yielding high strength electric field, over a large bandwidth, and perform preliminary experiments on single-shot THz imaging.
A. Development and optimization of intense ultrashort broadband THz pulse emission from gaseous media excited by focused single and 2-color femtoseconds laser pulses;
B. Tailoring the THz radiation (pulse shape, spectral content, polarization) produced by laser filamentation and multifilamentation;
C. Development of the methods for producing high resolution single shot 2D THz imaging.
October - December 2011
Value: 45.000 lei
January - December 2012
Value: 800.000 lei
- The equipment for high energy THz setup was assembled.
- Filaments in air were studied in various environment conditions.
January - December 2013
Value: 180.596,34 lei
- Enhancement of THz high field strength by two-color filamentation and multifilamentation.
A 17 TW laser system
delivering 25 fs laser pulses and with energy up to 300 mJ/pulse is
filamentation experiments. The laser pulse is split in two parts used
generation and THz detection. The most intense one is focused in
after being partially frequency doubled in a non linear BBO crystal to
two color filament and following THz radiation. The polarizations,
and the phases of the fundamental beam and its second harmonic should
controlled independently to further obtain an efficient conversion of
energy. The weaker part of the optical pulse is used for probing the
induced birefringence in a ZnTe crystal and by varying the optical path
the terahertz time domain can be sampled.
● The project’s first stages results are:
- Successful operation of the setup for single color and two color filamentation;
- Calibration of the electro-optical sampling method for THz detection;
- Novel design for a solid-state laser used as optical sources for THz generation.
stiintific pe anul 2013 este disponibil aici:
January - December 2014
Value: 127.500 lei
- Multiple THz high energy pulses were obtained by using two methods: spectral clipping and thin film beam polariser.
resume of the results (2011-2014), in English:
January - December 2015
Value: 111.930 lei
- The THz wave forms that were obtained using the intrinsic physical properties of the THZ-REEF laser induced plasma in two colors were consistent with the waveforms measured by other methods, in our case EO sampling using a ZnTe crystal.
- The time dependence of THz-REEF was modified by changing the relative phase between the two pulses and polarization fields offering their unique approach to detect THz wave amplitude and phase.
● Raportul stiintific pe anul 2015 este disponibil aici: | 2015 |
7. O. V. Grigore, G. Croitoru, T. Dascalu,
http://www.sciencedirect.com/science/article/pii/S0030399217300270 [2015 Impact Factor: 1.879].
6. C.A. Brandus, L. Gheorghe, T. Dascalu, “Efficient laser operation at 1.06μm in co-doped Lu3+, Nd3+:GaCa4O(BO3)3 single crystal," Opt. Mat. 42, 376-380 (2015);
http://www.sciencedirect.com/science/article/pii/S0925346715000580 [2015 Impact factor: 2.183].
5. T. Dascalu, G. Salamu, O. Sandu, F. Voicu, and
Note: This work was partially (30%) supported from this project.
4. M. Mernea, O. Calborean, O. Grigore, T. Dascalu, and D. F. Mihailescu, “Validation of protein structural models using THz spectroscopy: a promising approach to solve three-dimensional structures,”
Opt. Quantum. Electron. 46 (4), 505-514 (2014); http://link.springer.com/article/10.1007/s11082-013-9872-0 [2014 Impact factor: 0.987].
3. T. Dascalu, G. Salamu, O. Sandu, M. Dinca, and
http://dx.doi.org/10.1016/j.optlastec.2014.10.017 [2013 Impact Factor: 1.649]
Note: This work was partially (30%) supported from this project.
2. O. Grigore, O. Calborean, G. Cojocaru, R. Ungureanu, M. Mernea, M.P. Dinca, S. Avram, D.F. Mihailescu, and T. Dascalu, “High-intensity THz pulses application to protein conformational changes,” Rom. Rep. Physics 67(4),1251-1260 (2015). http://www.rrp.infim.ro/2015_67_4.html [2014 Impact factor: 1.517].
1. R. G. Ungureanu, O. V. Grigore, M. P. Dinca, G. V. Cojocaru, D. Ursescu and T. Dascalu, “Multiple THz pulse generation with variable energy ratio and delay,” Laser Phys. Lett. 12(4), 045301 (2015).
http://iopscience.iop.org/1612-202X/12/4/045301/article [2014 Impact factor: 2.458].
C. Brandus, G. Stanciu, A. Achim, S. Hau, F.
Voicu, L. Gheorghe, T.
Dascalu, ”Efficient Laser Emission in Nd:GdLuCOB and Nd:GdCOB Single
Siegman International School on Lasers 2016, 24-30 July 2016,
13. O. V. Grigore, G. Croitoru, T. Dascalu, M. Dinca, N. Pavel, “Edge-pumped Nd:YAG/YAG lens-shaped composite laser,” 7th EPS-QEOD EUROPHOTON CONFERENCE, Solid State, Fibre, and Waveguide Coherent Light Sources, 21-26 August, 2016, Vienna, Austria, PO-2.1 (poster presentation).
12. O. Grigore, R. Ungureanu, G. Cojocaru, R. Banici, M.P. Dinca, M. Mernea, S. Avram, D.F. Mihailescu, T. Dascalu, "Method for Generation Multiple High-Intensity THz Pulses within 1-100 ps Time Range," NATO Advanced Research Workshop on THz Diagnostics of CBRN effects and Detection of Explosives & CBRN, 3-6 November, 2015, Izmir, Turkey (invited presentation).
11. T. Dascalu, A. Popa, O. Grigore, M. P. Dinca, G. Cojocaru, R. Ungureanu, D. F. Mihailescu, “High-Intensity THz Pulses: Generation and Applications,” ROMOPTO 2015, 11th International Conference on Optics “Micro- to Nano-Photonics IV”, September 1-4, 2015, Bucharest, Romania; presentation I.I.4 (invited presentation)
● T. Dascalu, N. Pavel, G. Salamu, O. Grigore, F. Voicu, M. Dinca, "Sistem laser monolitic, compozit si compact cu livrare simultana a doua fascicule laser / Compact, composite, monolithic laser system with simultaneous emission of two laser beams," Romanian patent, OSIM application number A-100417 / 03.05.2013.
Note: The patent was partially (20%) supported from this project.
|Laboratory of Solid-State Quantum Electronics|