Intense THz source based on BNA organic crystal pumped at Ti:Sapphire   wavelength
  We report on high energy terahertz pulses by optical rectification (OR) in the organic crystal N-benzyl-2-methyl-4-nitroaniline (BNA) directly pumped by a conventional Ti:Sapphire (Ti:Sa) amplifier. The simple scheme provides an optical to terahertz conversion efficiency of 0.25% when pumped by a collimated laser pulses with duration of 50 fs and central wavelength of 800nm. The generated radiation spans frequencies between 0.2 and 3 THz. We measured the damage threshold as well as the dependency of the conversion efficiency on the pump fluence, pump wavelength, and pulse duration. 
Mostafa Shalaby, Carlo Vicario, Karunanithi Thirupugalmani, Srinivasan   Brahadeeswaran, Christoph P. Hauri
cond-mat.mtrl-sci cond-mat.other physics.optics