We demonstrate the existence of a spectrally narrow localized surface state, the so-called optical Tamm state, at the interface between one-dimensional magnetophotonic and nonmagnetic photonic crystals. The state is spectrally located inside the photonic band gaps of each of the photonic crystals comprising this magnetophotonic structure. This state is associated with a sharp transmission peak through the sample and is responsible for the substantial enhancement of the Faraday rotation for the corresponding wavelength. The experimental results are in excellent agreement with the theoretical predictions.

Thin films of polycrystalline cerium substituted yttrium iron garnet (CeYIG) were grown on an yttrium iron garnet (YIG) seed layer on Si and Si-on-insulator substrates by pulsed laser deposition, and their optical and magneto-optical properties in the near-IR region were measured. A YIG seed layer of ~30 nm thick processed by rapid thermal anneal at 800°C provided a virtual substrate to promote crystallization of the CeYIG. The effect of the thermal budget of the YIG/CeYIG growth process on the film structure, magnetic and magnetooptical properties was determined.

Photonic integrated circuits require magneto-optical (MO) materials for making nonreciprocal devices such as isolators and circulators. The most successful MO materials are rare-earth-substituted iron garnets, but these can be challenging to grow on silicon without a seed layer, which introduces spacing loss between the waveguide and the MO cladding. A pulsed-laser deposition (PLD) method is used for making MO Ce:YIG (Ce 1 Y 2 Fe 5 O 12 )/YIG (Y 3 Fe 5 O 12 ) bilayer or trilayer films on different substrates, including silicon, quartz, and Gd 3 Ga 5 O 12 (GGG), in which a multilayer film is deposited in one run and then annealed. A YIG seed layer grown above the MO Ce:YIG facilitates recrystallization during ex situ rapid thermal annealing, which results in a reduced thermal budget and simplified deposition process. A monolithically integrated optical isolator was demonstrated by direct deposition of a bilayer Ce:YIG/YIG capping layer onto a siliconon-insulator resonator. The device exhibited an insertion loss of 7.4 ± 1.8 dB and an isolation ratio of 13.0 ± 2.2 dB within the telecommunication window (λ = 1564.4 nm), which outperforms previously reported monolithic isolators.

Both polycrystalline and single-crystal films of iron-substituted strontium titanate, SrðTi 0.65 Fe 0.35 ÞO 3−δ , prepared by pulsed laser deposition, show room-temperature magnetism and Faraday rotation, with the polycrystalline films exhibiting higher saturation magnetization and Faraday rotation. The magnetic properties vary with the oxygen pressure at which the films are grown, showing a maximum at pressures of approximately 4 μ Torr at which the unit-cell volume is largest. The results are discussed in terms of the oxygen stoichiometry and corresponding Fe valence states, the structure and strain state, and the presence of small-volume fractions of metallic Fe in single-crystal films grown at the optimum deposition pressure. Integration of magneto-optical polycrystalline films on an optical-waveguide device demonstrates a nonreciprocal phase shift.

The magnetic and magneto-optic properties of epitaxial CeY 2 Fe 5 O 12 (Ce∶YIG) and Y 3 Fe 5 O 12 (yttrium iron garnet or YIG) thin films grown by pulsed laser deposition on gadolinium gallium garnet substrates are determined. An enhanced Faraday effect is known to result from Ce substitution into the yttrium iron garnet lattice, and here we characterize the magneto-optic Kerr effect, as well as the magnetic hysteresis and ferromagnetic resonance response that result from the Ce substitution. X-ray diffraction analysis reveals a high crystallographic quality for the Ce∶YIG films. Measurements of the magneto-optic Kerr effect for two different wavelengths demonstrate that the Ce∶YIG exhibits an up-to-tenfold increase in Kerr rotation compared to YIG. The Ce∶YIG has a slightly larger magnetic moment, as well as increased magnetic damping and higher magnetic anisotropy compared to YIG with a dependence on the crystalline orientation. By specific cerium substitution in YIG, our results show that the engineering of a large Kerr effect and tailored magnetic anisotropy becomes possible as required for magneto-optically active spintronic devices.