Dual-frequency vertical-external-cavity surface-emitting laser device for THz generation and method for generating THz

The invention relates to a laser device (100) for generating an optical wave (107) including at least two frequencies, wherein one such laser device (100) includes: a first element (111) including a gain region (104), a second mirror (106) that is separate from the first element (111) and is arranged so as to form, together with the first mirror (103), an optical cavity including the gain region (104), and means (120) for pumping the gain region (104) so as to generate the optical wave (107). Said laser device (100) further includes: means for shaping the light intensity of the optical wave (107), which means are arranged to select at least two transverse modes of the optical wave (107); and means for shaping the longitudinal and/or transverse phase profile of the optical wave (107), which means are arranged to adjust the at least two transverse modes of the optical wave (107).