A photonic device (100, 200) comprising: a first mode converter (110, 210) configured to: receive an optical signal having a first component and a second component propagating in different respective polarization states; and convert one or both of the first component and the second component to both propagate in different respective modes of a same polarization state; a modulator (120, 220) configured to: receive optical output of the first mode converter (110, 210); and apply a controlled gain, a controlled phase shift, or both, to both the first component and the second component as output by the first mode converter (110, 210); and a second mode converter (130, 230) configured to: receive optical output of the modulator (120, 220), the optical output comprising the first component and the second component propagating in said different respective modes of the same polarization state; and convert one or both of the first component and the second component as output by the modulator (120, 220) to cause the first component and the second component to propagate in different respective polarization states, the photonic device (100, 200) further comprising an additional modulator (105, 135) operatively coupled to an input of the first mode converter (110, 210) or operatively coupled to an output of the second mode converter (130, 230), the additional modulator (105, 135) cooperating with the modulator (120, 220) and configured to apply another controlled gain, another controlled phase shift, or both, to both the first component and the second component of the optical signal, when the first component and the second component are propagating in said different polarization states, said photonic device (100, 200) characterized in that, the modulator (120, 220) exhibits a first difference in modulation strength across each of said different respective modes of the same polarization state, and wherein the additional modulator (105, 135) exhibits a second difference in modulation strength across modes of said different polarization states, the second difference in modulation strength at least partially compensating for the first difference in modulation strength. a first mode converter (110, 210) configured to: receive an optical signal having a first component and a second component propagating in different respective polarization states; and convert one or both of the first component and the second component to both propagate in different respective modes of a same polarization state; a modulator (120, 220) configured to: receive optical output of the first mode converter (110, 210); and apply a controlled gain, a controlled phase shift, or both, to both the first component and the second component as output by the first mode converter (110, 210); and a second mode converter (130, 230) configured to: receive optical output of the modulator (120, 220), the optical output comprising the first component and the second component propagating in said different respective modes of the same polarization state; and convert one or both of the first component and the second component as output by the modulator (120, 220) to cause the first component and the second component to propagate in different respective polarization states, the photonic device (100, 200) further comprising an additional modulator (105, 135) operatively coupled to an input of the first mode converter (110, 210) or operatively coupled to an output of the second mode converter (130, 230), the additional modulator (105, 135) cooperating with the modulator (120, 220) and configured to apply another controlled gain, another controlled phase shift, or both, to both the first component and the second component of the optical signal, when the first component and the second component are propagating in said different polarization states, said photonic device (100, 200) characterized in that, the modulator (120, 220) exhibits a first difference in modulation strength across each of said different respective modes of the same polarization state, and wherein the additional modulator (105, 135) exhibits a second difference in modulation strength across modes of said different polarization states, the second difference in modulation strength at least partially compensating for the first difference in modulation strength.