Ce:YIG/Silicon-on-Insulator waveguide optical isolator realized by adhesive bonding

Abstract

A waveguide optical isolator realized by adhesive bonding of a garnet die, containing a Ce:YIG magneto-optic layer, on a silicon-oninsulator waveguide circuit is demonstrated. The die was bonded on top of an asymmetric Mach-Zehnder interferometer using a 100nm thick DVS-BCB adhesive bonding layer. A static magnetic field applied perpendicular to the light propagation direction results in a non-reciprocal phase shift for the fundamental quasi-TM mode in the hybrid waveguide geometry. A maximum optical isolation of 25 dB is obtained. References and links 1. K. E. Stubkjaer and M. B. Small, " Noise properties of semiconductor lasers due to optical feedback," 2011 Optical Society of America

Si-integrated ultrathin films of phase-pure Y3Fe5O12 (YIG) via novel two-step rapid thermal anneal

“…In addition, proximity-based spin-pumping effects diminish inversely with the thickness of the YIG proximity layer so ultrathin YIG is desired but difficult to integrate with Si [18]. Fortunately, the photonics community has been improving the growth of ultrathin YIG onto semiconductor-compatible substrates for on-chip optical isolators [15,[19][20][21][22][23].…”

Compact Mach–Zehnder Interferometer Ce:YIG/SOI Optical Isolators

“…To avoid the need for phase-matching, instead of non-reciprocal polarization rotation, the non-reciprocal phase shift (NRPS) experienced by the TM polarized mode due to the presence of a lateral magnetic field is typically utilized in a waveguide configuration [3]. The nonreciprocal material can be bonded [4][5][6] or deposited [7] on top of the waveguide circuit to realize an optical isolator. Currently, the material quality of the deposited material is still inferior to the as-grown material.…”

Monolithic on-chip nonreciprocal photonics based on magneto-optical thin films

“…Two routes have been pursued to resolve the integration challenge: the hybrid approach which relies on wafer bonding of garnet crystals [7][8][9][10][11] , and the monolithic approach which directly deposits polycrystalline ferromagnetic oxides or doped semiconductors/polymers 12-15 on semiconductor substrates. The former approach can leverage the large Verdet constant and low material absorption in single-crystalline garnets to achieve good isolation performance; however, the wafer bonding process required by this approach can limit fabrication throughput and yield.…”