Arbitrary control of the flow of light using pseudomagnetic fields in photonic crystals at telecommunication wavelengths

Pseudomagnetic fields (PMFs) can manipulate photons in a similar way that magnetic fields control electrons. However, the PMF-based control over light has been restricted to simple waveguiding of the Landau level states, which hinders the application of PMFs in practical photonic integrated circuits. Here, we propose a universal and systematic methodology to design complex nonuniform PMFs and arbitrarily control the flow of light in silicon photonic crystals at telecommunication wavelengths. As proofs of concept, an S-bend (with a low insertion loss of <1.83 dB) and a 50:50 power splitter (with a low excess loss of <2.11 dB and imbalance of less than ±0.5 dB) based on PMFs are experimentally demonstrated. A high-speed data transmission experiment is performed on these devices with 140-Gb/s four-level pulse amplitude modulation signals to prove their applicability in real communication systems. The proposed method offers a paradigm for exploring magnetic-field-related physics with neutral particles and developing nanophotonic devices with PMF-induced states beyond the Landau level states and the topological edge states.