RCAS: Thematic Center for Quantum Photonics

We develop optoelectronic technologies and key components for applications in quantum technology, which are still subject to many technological constraints.

Focusing project

Quantum Photonic Applications based on Emergent Materials

Photonic design for controlling emission of single photon emitter

Crystallinity of Electrodes: Extraction and Modelling of Contact Resistance on 2D Material Surfaces in the Nanometer Regime for Device Applications

Quantum Photonic Applications of Novel Materials

Project Summary

The emerging field of quantum technology has opened up new opportunities for the development of new optoelectronic devices. For future quantum technology, quantum photonic devices will play a crucial role in various aspects and bring revolutionary changes. This project aims at developing three critical areas including:
(1) Single-photon emitters with high brightness, efficiency, and indistinguishability.
(2) Superconducting single-photon detectors based on high-quality superconducting materials to achieve high sensitivity, fast response, high detection efficiency, and low noise.
(3) Quantum photonic chips and exploration of novel physical mechanisms to improve quantum photonic devices.
The developed quantum photonic devices will be the foundation for future developments in quantum information technology.

Expected Outcomes

Developing new device designs to improve the performances of single-photon sources and single-photon detectors, exploring the mechanisms of light-matter interactions and new techniques for quantum state manipulation, and developing novel growth techniques for materials to expand the practical applications of quantum photonics.

Photonic design for controlling emission of single photon emitter

Project Summary

Once the generic properties of a single photon emitter are known, the next step is to tailor its emission characteristics so that the emitted single photon can be utilized for quantum applications in successive systems. A few key features of the single photon could be manipulated at the emission stage, including the emission rate, emission direction, and polarization state of single photons. In this project, specialized photonic structures will be developed to control of single photon emissions, particularly focusing on the design of cavities, waveguide, and chiral structures that can enable manipulations of single photons.

Expected Outcomes

Achieving efficient single-photon sources, controlling chiral polarization states, and routing single photons to propagate along designated in-plane directions for coupling into photonic integrated chips.

Crystallinity of Electrodes: Extraction and Modelling of Contact Resistance on 2D Material Surfaces in the Nanometer Regime for Device Applications

Project Summary

The high contact resistance at electrodes and 2D material interfaces is one major bottleneck for further device performance improvement of 2D material devices. We have demonstrated that by using polycrystalline antimonene as the contact electrodes through traditional photolithography and metal lift-off procedures, reduced contact resistance and enhanced device performances can be observed. However, due to its weak thermal and chemical endurance, antimonene may not be a promising candidate as the contact electrodes in semiconductor fabrication lines. In our preliminary study, we have demonstrated that the crystallinity of the contact electrodes may be the major issue influencing the contact resistance at the metal/2D material interfaces. Therefore, the goal of this project is to explore the actual mechanism responsible for the reduced contact resistance at the metal/2D material interfaces with enhanced electrode crystallinity. To reduce the influence of channel resistance to the measurement results, conductive atomic force microscope will be adopted to extract the actual contact resistance of different contact metals in the nanometer regime. First-principles modelling will be performed to gain deeper understanding. We also explore the opportunity to apply the low-resistance contacts to the compact light-emitting devices.

Expected Outcomes

Exploiting low-resistance contacts to optimize 2D FET device performance with the current density > 100 µA/µm and the field effect mobility > 100 cm² V⁻¹·s⁻¹, and applying low-resistance contacts to 2D quantum light sources and microcavity lasers.

Our Members

Focusing project

Quantum Photonic Applications based on Emergent Materials

Photonic design for controlling emission of single photon emitter

Crystallinity of Electrodes: Extraction and Modelling of Contact Resistance on 2D Material Surfaces in the Nanometer Regime for Device Applications

Our Members

Wen-Hao Chang

Min-Hsiung Shih

Chao-Cheng Kaun

Shih-Yen Lin

Shu-Wei Chang

Chi Chen

Yu-Chen Chen