Publications by authors named "Takako Hirokawa"
Article Synopsis
- Researchers have designed and successfully created a slotted photonic crystal with features as small as 40 nm using a standard silicon photonics process.
- The unique design increases the electric field energy by four times compared to traditional slotted photonic crystals by using a specialized unit cell shape that enhances optical energy localization.
- This work paves the way for future development of advanced photonic structures that could improve applications like biosensing and light manipulation on-chip.
We present an on-chip wavelength reference with a partial drop ring resonator and germanium photodetector. This approach can be used in ring-resonator-based wavelength-selective switches where absolute wavelength alignment is required. We use the temperature dependence of heater resistance as a temperature sensor.
View Article and Find Full Text PDFIn this paper, we demonstrate that forward bias (+0.9V) of a high-speed silicon (Si) optical Mach-Zehnder modulator (MZM) increases the radio-frequency (RF) link gain by 30 dB when compared to reverse bias operation (-8V). RF applications require tunable, narrowband electro-optic conversion with high gain to mitigate noise of the optical receiver and realize high RF spur-free dynamic range.
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