Photonic Aharonov–Bohm effect in photon–phonon interactions. Non-reciprocal phase shift induced by an effective magnetic flux for light. Electrically driven nonreciprocity induced by interband photonic transition on a silicon chip. Optical isolator using two tandem phase modulators. Reconfigurable light-driven opto-acoustic isolators in photonic crystal fibre. Linear isolation is demonstrated with simultaneously 39 dB contrast and 10 dB bandwidth up to ~200 MHz. We demonstrate isolators at wavelengths one octave apart near 1,550 nm and 780 nm, fabricated from the same lithium-niobate-on-insulator wafer. Our concept is implemented using a lithium niobate racetrack resonator in which phonon-mediated 13 photonic Autler–Townes splitting 10, 16, 23, 24 breaks the chiral symmetry of the resonant modes. Here we demonstrate an electrically driven optical isolator design that leverages the unbeatable transparency of a short, high-quality dielectric waveguide, with the strong attenuation from a critically coupled absorber. So far, no magnetless alternative 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 has managed to simultaneously combine linearity (that is, no frequency shift), linear response (that is, input–output scaling), ultralow insertion loss and large directional contrast on-chip. Optical isolators today are exclusively built on magneto-optic principles but are not readily implemented within photonic integrated circuits.

Paper on optical isolator