Cascaded ring resonator-based temperature sensor with simultaneously enhanced sensitivity and range.

Area of Science:

• Photonics
• Optical Sensors
• Materials Science

Background:

• Silicon photonics offers a scalable platform for integrated optical devices.
• Temperature sensors are crucial for various applications, including environmental monitoring and industrial process control.
• Enhancing both sensitivity and range of optical temperature sensors remains a key challenge.

Purpose of the Study:

• To develop a silicon photonic temperature sensor with simultaneously enhanced sensitivity and sensing range.
• To investigate the use of cascaded ring resonators (CRR) for dual performance improvement.
• To demonstrate a cost-effective fabrication process for the proposed sensor.

Main Methods:

• Design and fabrication of a cascaded ring resonator (CRR) system using two micro ring resonators with tailored geometric parameters.
• Leveraging differences in temperature sensitivities and free spectral ranges (FSRs) of the individual resonators.
• Utilizing a single-mask complementary metal-oxide-semiconductor (CMOS)-compatible fabrication process.

Main Results:

• Achieved a significantly enhanced temperature sensitivity of 293.9 pm/°C, 6.3 times higher than individual ring resonators.
• Demonstrated a 5.3-fold enhancement in the temperature sensing range.
• Successful fabrication using a standard CMOS-compatible process.

Conclusions:

• The proposed CRR-based silicon photonic temperature sensor effectively achieves simultaneous enhancement in sensitivity and range.
• The tailored design of micro ring resonators is key to the dual performance improvement.
• The CMOS-compatible fabrication ensures potential for scalable and cost-effective manufacturing.