Abstract: A photoconductive switch for generating or detecting terahertz radiation (TR) is provided. The photoconductive switch may comprise at least a first and a second pair of electrodes (EV, EH, EGR) on a surface (SS) of a photoconductive substrate, wherein the electrodes of the first pair are separated by a first gap comprising at least a plurality of first rectilinear sections (GV) extending along a first direction (x) and the electrodes of the second pairs are separated by a second gap comprising at least a plurality of second sections (GH) extending along a second direction (y), different from the first direction. The photoconductive switch may further comprise a patterned opaque layer (PML) selectively masking portions of the gaps between the electrodes. Methods and devices for generating and detecting terahertz radiation comprising such photoconductive switches are also provided.

Abstract: A photoconductive switch for generating or detecting terahertz radiation (TR) is provided. The photoconductive switch may comprise at least a first and a second pair of electrodes (EV, EH, EGR) on a surface (SS) of a photoconductive substrate, wherein the electrodes of the first pair are separated by a first gap comprising at least a plurality of first rectilinear sections (GV) extending along a first direction (x) and the electrodes of the second pairs are separated by a second gap comprising at least a plurality of second sections (GH) extending along a second direction (y), different from the first direction. The photoconductive switch may further comprise a patterned opaque layer (PML) selectively masking portions of the gaps between the electrodes. Methods and devices for generating and detecting terahertz radiation comprising such photoconductive switches are also provided.

Abstract: The invention relates to the field of optical parametric oscillators (OPO), especially to an essentially vertical monolithic system (S) for parametric conversion from a pump wave with a pump wavelength, said system comprising at least two resonant cavities (6, 7). Said cavities are coupled by at least one coupling mirror (3), at least one of the cavities comprising an active non-linear medium, and the at least one coupling mirror being arranged in such a way that the parametric frequencies associated with the pump wavelength are located in the stop line of the at least one mirror for an injection direction of the pump wave essentially according to the axis of the system.

Abstract: The invention relates to the field of optical parametric oscillators (OPO), especially to an essentially vertical monolithic system (S) for parametric conversion from a pump wave with a pump wavelength, said system comprising at least two resonant cavities (6, 7). Said cavities are coupled by at least one coupling mirror (3), at least one of the cavities comprising an active non-linear medium, and the at least one coupling mirror being arranged in such a way that the parametric frequencies associated with the pump wavelength are located in the stop line of the at least one mirror for an injection direction of the pump wave essentially according to the axis of the system.