| 研究開始時の研究の概要 |
In this project, we will focus and develop the novel Group-IV semiconductor based linear and nonlinear waveguide photonic devices. We will design the Group-IV semiconductor based functional devices such as the straight waveguide, micro-ring resonator,and add-drop devices by using the free-carrier absorption, nonlinear Kerr effect, and other nonlinear optical effects to construct all-optical modulation, phase-shift keying data encoder/decoder, all-optical wavelength converter and all-optical logic gate in the chip-to-chip and intra-chip transmission.
|
| 研究実績の概要 |
In this JSPS research fund between Apr.2022 and Nov. 2022, we worked on 25-Gbps all-optical data processing based on the silicon carbide (SiC) micro-ring resonator. This SiC micro-ring resonator with a nonlinear refractive index of 3.05×10-14 cm2/W of is retrieved from the pump-probe analysis. In addition, the eye diagram of the wavelength-converted data exhibits its signal-to-noise and on/off-extinction ratios (SNR and ER) of 5.6 dB and 11.8 dB, respectively. For the 25-Gbps data inversion, the SNR and ER can be evaluated as 4.8-dB and 10.2-dB, respectively. In addition, the rising and falling time in an ultrafast switching is also measured as less than 22 ps. This phenomenon causes all-optical data processing including both wavelength switching and format conversion. Therefore, the highly nonlinear optical SiC micro-ring resonator can achieve error-free operation with a bit-error ratio (BER) lower than 1×10-5 at 25 Gbps.
In taddition, the O-band Ge p-i-n photodetector (PD) are demonstrated to receive the NRZ-OOK data beyond 60 Gbps. After optimizing the transmission-line designs, the Ge PD improves its RLC response to enhance the receiving bandwidth. Decreasing the transmission-line length from 280 μm to 80 μm extends the S11 spectral response from 51 to 57 GHz. When the Ge PD is used to receive the optical NRZ-OOK data stream, the long-electrode device exhibts 53-Gbps receiving performance. The short-electrode Ge PD receives the NRZ-OOK data beyond 56 Gbps and 60 Gbps under error-free communication criterion of BER<10－12 and BER<10－9 , respectively.
|
