report ultrafast carrier dynamics in hybrid CdSe nanorod / poly(3-hexythiophene) (P3HT) bulk heterojunction films measured by time-resolved terahertz spectroscopy, and compare to the well studied P3HT/phenyl-C61-butyric acid methyl ester (PCBM) blend. Both films show an improved peak photoconductivity compared to P3HT alone, consistent with efficie...
Published in Science in China Series G: Physics, Mechanics and Astronomy
The optical property and spectroscopy of selected kinds of lubricating oil are studied based on the terahertz time-domain spectroscopy (THz-TDS) in the spectral range of 0.3–1.6 THz. The samples are classified by their characteristics via the near-infrared spectrum. The experimental results reveal that lubricating oil is more sensitive in the range...
Published in Science in China Series G: Physics, Mechanics and Astronomy
The carrier dynamics and terahertz photoconductivity in the n-type silicon (n-Si) as well as in the p-type Silicon (p-Si) have been investigated by using femtosecond pump-terahertz probe technique. The measurements show that the relative change of terahertz transmission of p-Si at low pump power is slightly smaller than that of n-Si, due to the low...
Situées entre l'infrarouge et les micro-ondes, les ondes dites "terahertz" (THz) ont les propriétés de passer aussi bien à travers la peau et les vêtements que les papiers, le bois, le carton ou encore le plastique. Autant d'atouts qui permettent d'envisager de multiples applications dans les secteurs de l'imagerie médicale, de la spectroscopie, de...
The terahertz radiation produced by a 2-color femtosecond laser scheme strongly saturates and develops an oscillatory behavior with increasing power of the driving femtosecond laser pulses. This is explained by the formation of a plasma channel due to filamentation. Due to dispersion inside the filament and the Gouy phase shift, the phase differenc...
Published in Chinese Science Bulletin
Gyrotrons are the most powerful terahertz sources and have potential applications in many areas. A terahertz gyrotron oscillator with a pulsed solenoid producing up to an 8 T magnetic field has been designed, constructed and tested. In a 7.96 T magnetic field, 3 kW output power radiations at 0.22 THz frequency have been generated.
2009 IEEE MTT-S International Microwave Symposium, IMS 2009. Boston, MA, USA, 7 - 12 June 2009
Le phénomène de filamentation laser apparaît spontanément dans un faisceau laser infra-rouge se propageant dans l'air si sa puissance crête excède quelques Gigawatts. À ce régime d'intensité le faisceau s'effondre sur lui même par effet Kerr et un équilibre dynamique s'installe entre la diffraction, l'effet Kerr et la défocalisation par l'air ionis...
Le travail de thèse a porté de façon générale sur l'étude des transitions dans les hétérostructures à cascade quantique. Deux types de structures ont été étudiés, le laser émettant dans la gamme des THz et le détecteur moyen infrarouge. Cette étude a été menée en champ magnétique appliqué perpendiculairement ou parallèlement aux couches des hétéros...
The transition-Cherenkov terahertz radiation from a femtosecond laser filament in air is enhanced by three orders of magnitude in the presence of a longitudinal static electric field, while the radiation pattern and the polarization remain the same. An amplified longitudinal electron current inside the filament is responsible for this amplified ter...
