Photonic chip comprising: - a support substrate provided with a front face; - a waveguide layer resting on the front face; - two single Mach-Zehnder modulators (100a, 100b), referred to respectively as modulator I and modulator Q, so that the photonic chip forms an IQ modulator, the two Mach-Zehnder modulators being formed on and/or in the waveguide layer, each comprising two modulation branches, referred to as first branch (101a, 101b) and second branch (102a, 102b), arranged between an optical input and an optical output so that a light ray injected at the optical input is split into a first ray and a second ray, intended to be modulated by, respectively, the modulator I and the modulator Q, and are then recombined at the optical output, each of the two modulation branches of a Mach-Zehnder modulator comprises a modulation portion (105a, 105b, 106a, 106b) formed by a waveguide, referred to as a modulation waveguide, and a modulation element, the modulation element being designed to modulate the phase of a ray capable of being guided by the modulation waveguide, the second branch (102a, 102b) also comprising a phase-shift module (107a, 107b) designed to impose a fixed phase shift onto a light ray capable of being guided by said second branch (102a, 102b), the first branch and the second branch of the modulator I being connected, at one of the ends thereof, by an intermediate optical input, referred to as input I, and, at the other of the ends thereof, by an intermediate optical output, referred to as output I, the first branch and the second branch of the modulator Q being connected, at one of the ends thereof, by another intermediate optical input, referred to as input Q, and, at the other of the ends thereof, by another intermediate optical output, referred to as output Q; the photonic chip also comprises a ray splitter and a ray combiner, the ray splitter comprising two waveguides, referred to respectively as input guide I and input guide Q, the input guide I and the input guide Q connecting the optical input with, respectively, the input I and the input Q, so that the first ray and the second ray are injected at, respectively, the input I and the input Q, the ray combiner comprising two waveguides, referred to respectively as output guide I and output guide Q, the output guide I and the output guide Q connecting an optical output with, respectively, the output I and the output Q; characterized in that the photonic chip comprises two single semiconductor optical amplifiers (114c, 115c), referred to respectively as amplifier I and amplifier Q, carried, respectively, by the output guide I and the output guide Q. - a support substrate provided with a front face; - a waveguide layer resting on the front face; - two single Mach-Zehnder modulators (100a, 100b), referred to respectively as modulator I and modulator Q, so that the photonic chip forms an IQ modulator, the two Mach-Zehnder modulators being formed on and/or in the waveguide layer, each comprising two modulation branches, referred to as first branch (101a, 101b) and second branch (102a, 102b), arranged between an optical input and an optical output so that a light ray injected at the optical input is split into a first ray and a second ray, intended to be modulated by, respectively, the modulator I and the modulator Q, and are then recombined at the optical output, each of the two modulation branches of a Mach-Zehnder modulator comprises a modulation portion (105a, 105b, 106a, 106b) formed by a waveguide, referred to as a modulation waveguide, and a modulation element, the modulation element being designed to modulate the phase of a ray capable of being guided by the modulation waveguide, the second branch (102a, 102b) also comprising a phase-shift module (107a, 107b) designed to impose a fixed phase shift onto a light ray capable of being guided by said second branch (102a, 102b), the first branch and the second branch of the modulator I being connected, at one of the ends thereof, by an intermediate optical input, referred to as input I, and, at the other of the ends thereof, by an intermediate optical output, referred to as output I, the first branch and the second branch of the modulator Q being connected, at one of the ends thereof, by another intermediate optical input, referred to as input Q, and, at the other of the ends thereof, by another intermediate optical output, referred to as output Q; the photonic chip also comprises a ray splitter and a ray combiner, the ray splitter comprising two waveguides, referred to respectively as input guide I and input guide Q, the input guide I and the input guide Q connecting the optical input with, respectively, the input I and the input Q, so that the first ray and the second ray are injected at, respectively, the input I and the input Q, the ray combiner comprising two waveguides, referred to respectively as output guide I and output guide Q, the output guide I and the output guide Q connecting an optical output with, respectively, the output I and the output Q; characterized in that the photonic chip comprises two single semiconductor optical amplifiers (114c, 115c), referred to respectively as amplifier I and amplifier Q, carried, respectively, by the output guide I and the output guide Q.