Optical isolator definition free#

Integrated optical isolators have been a longstanding challenge for photonic integrated circuits (PIC). Since its operation does not require an electromagnet or a permanent magnet, the suggested circulator is much more compact, being able to reach footprints in the range of three orders of magnitude smaller, when compared to other circulator designs referred to in the literature and the presented results can be useful for the design of other nonreciprocal devices with reduced dimensions for optical communication systems. Two- and three-dimensional simulations of the device performed with full-wave electromagnetic solvers based on the finite element method demonstrate that, at the 1550 nm wavelength, the insertion loss, isolation, and reflection levels are equal to or better than −1 dB, −14 dB, and −20 dB, respectively. By maximizing the incorporation of europium to its molecular formula, the magneto-optical material can remain in the saturated magnetic state even in the absence of an external DC magnetic field. To the best of the authors' knowledge, the proposed integrated TE optical circulator is the first experimental demonstration of this device in silicon photonics.Ī three-port circulator for optical communication systems comprising a photonic crystal slab made of a magneto-optical material in which an magnetizing element is not required to keep its magnetic domains aligned is suggested for the first time. Finally, it has been theoretically shown that the insertion loss can be reduced below 6 dB with design and fabrication improvements. In the former case, an optical isolation ratio as large as 30 dB is measured at 1555 nm with an insertion loss of 18 dB, while for the broadband circulator an optical isolation larger than 15 dB is guaranteed over more than 14 nm (1.75 THz) for all port-combinations with an insertion loss between 14 dB and 18dB at 1560 nm.

Optical isolator definition free#

Two isolators/circulators are fabricated with small and large free spectral range, respectively. The nonreciprocal behavior is induced through an energy-efficient integrated electromagnet with a minimum power consumption of 3 mW.

To achieve this goal, an integrated adiabatic coupler and a broadband polarization rotator are designed and optimized.

In this work, we demonstrated broadband optical isolators and circulators for TE polarized light based on heterogeneous bonding on the silicon photonics platform. However, most integrated semiconductor lasers emit TE polarized light, which indicates the need to find a reliable solution for this polarization.

In silicon photonics, heterogeneous integration of magneto-optic garnet bonded on a pre-patterned silicon layer has been demonstrated to be an effective solution for manufacturing optical isolators and circulators for TM polarized light. Optical isolators and circulators are fundamental building block in photonic integrated circuits to block undesired reflections and routing light according to a prescribed direction.