High-Performance Polarization-Independent Beam Splitters and MZI in Silicon Carbide Integrated Platforms for Single-Photon Manipulation

Abstract

Silicon carbide (SiC), having various intrinsic color centers, is a highly promising optical materials for making monolithic quantum integrated photonic circuits, by combining the single-photon sources with the integrated photonic components in SiC integrated platforms. Based on this quantum-material platform, we propose polarization-independent 1 × 2 and 2 × 2 multimode interference based beam splitters and Mach-Zehnder interferometers (MZI) for single-photon manipulation with unknown polarization states. We experimentally demonstrate that these devices exhibit excellent performances with incident light at both high power (>-10 dBm) and ultra-low power (<-100 dBm). The 1 × 2 and 2 × 2 beam splitters have low average loss of 1 dB and 1.5 dB, with a wide bandwidth of >100 nm and >70 nm, respectively. The MZI exhibits high transmittance, with a visibility of 98.3% and 97.6% for the high-power measurement and an even higher visibility of 99.0 ± 0.4% and 98.7 ± 0.6% for the ultra-low power measurement, for the TE and TM polarizations, respectively.

Novel Photonic Applications of Silicon Carbide

“…SiCOI stacks with a polytype of 4H, 3C and amorphous have been demonstrated by different formation methods, and high-quality-factor (>1 million) microring resonators have been reported. A lot of passive and active devices are demonstrated, such as beam splitter, polarization beam splitter, modulator, frequency comb, etc [ 23 , 38 , 63 , 74 ].…”

“…Based on these demonstrations of high-performance SiC microresonators, as well as other SiC integrated devices, SiC integrated platforms can be potentially applied to classical and nonclassical optical communication systems for signal processing, logic gate, modulation, filtering, (de)multiplexing, etc. [ 5 , 24 , 63 , 64 , 65 , 66 , 67 , 68 ].…”

Experimental characterization of the thermo-optic coefficient vs. temperature for 4H-SiC and GaN semiconductors at the wavelength of 632 nm

“…In all of said photonic applications, the knowledge of the precise value of the refractive index is of paramount importance for the correct design of devices, especially in those cases where resonance principles are utilized to carefully select the wavelength of operation, such as in ring resonators or multimode interference lters [10,13,20]. However, it is well known that temperature has a notable impact on refractive index, through a phenomenon known as the thermo-optic effect (TOE), which can negatively alter the device performance if it is not carefully taken into consideration in the design phase.…”

Methods and applications of on-chip beam splitting: A review

“…Integrated optical devices including splitters mainly include optical interferometer [133][134][135][136][137][138], optical coupler [139-141], optical modulator [82-98], optical switch [142], optical router [143], mixer [144], optical isolator [145]. They play different roles in wavelength division multiplexing, time division multiplexing, space division multiplexing and other multiplexing systems, so as to meet the growing demand for communication capacity.…”