Lyingbetweenradiofrequencyandinfraredradiation,terahertz(THz)waveencounterslotsofdifficultiestoproduce,detect,transmit,andmodulate.GreateffortshavebeenmadetoconstructTHzdevices,includingsources,detectors,switches,modulators,lenses,andfilters.However,onlymoderateprogresseshavebeenmadeinTHzgenerationanddetection.Furthermore,thedevicesandtechniquestocontrolandmanipulateTHzwavesarestillinitsinfancy.Therefore,itisstillachallengetodateto