Widely tunable terahertz-wave generation using an N-benzyl-2-methyl-4-nitroaniline crystal

Widely tunable terahertz (THz)-wave generation using difference frequency generation (DFG) in an organic N-benzyl-2-methyl-4-nitroaniline (BNA) crystal was demonstrated. To our knowledge, this is the first report of THz-wave generation by BNA DFG. Large, high-quality single crystals of BNA (ϕ 8 mm×30 mm) were grown using the vertical Bridgman method. The nonlinear optical (NLO) coefficient d33 of the BNA crystal is ~234 pm/V, which is the largest value reported for any yellow NLO material. The collinear phase-matching condition of the type-0 configuration is satisfied using a 0.7-1 μm band pump wavelength. We generated THz waves using an organic BNA crystal; the generation range is 0.1-15 THz.