Under CopyrightL'huillier, J.A.J.A.L'huillierTorosyan, G.G.TorosyanTheuer, M.M.TheuerRau, C.C.RauAvetisyan, Y.Y.AvetisyanBeigang, R.R.Beigang2022-03-037.7.20102007https://publica.fraunhofer.de/handle/publica/21305410.24406/publica-r-21305410.1007/s00340-006-2528-zOptical rectification of femtosecond pulses in nonlinear materials is an efficient method to generate ultra-short terahertz (THz) pulses in a wide frequency range extending from 100 GHz to well above 10 THz. Lithium niobate (LN) is well suited for such a purpose despite the high absorption in the THz range. In this part we will focus on the various experimental realizations to produce THz radiation in bulk, periodically, aperiodically and two-dimensionally poled LN. The possible bandwidth, tunability and the techniques to overcome the high absorption will be discussed as well.enTerahertz radiationlithium-niobate621journal article