Generation of broadband terahertz Laguerre-Gaussian beam

摘要

The light beam with Laguerre-Gaussian (LG) mode has attracted remarkable attentions these days because of its unique features and possible applications [1]. This mode has a phase singularity at the center of the beam, and has phase distribution proportional to the angular coordinate. Because the phase front of this mode is twisted around the center of the beam, LG beam can transfer orbital angular momentum [2]. In optical frequency region, LG beam is applied to optical tweezers [3], Stimulated emission depletion microscope [4], and many other experiments. LG beam in the terahertz (THz) frequency region should also have possible applications of THz wave such as momentum transfer to low-energy elementary excitations, THz communication systems, etc.