Ryoichi Ishihara

Associate Professor, Group leader

Qutech, Dep. Quantum and Computer Engineering, Faculty of Electrical Engineering, Mathematics and Computer Science, Delft University of Technology

Ishihara-lab focuses on the integration technologies for unconventional electronic systems; quantum computers, quantum sensors, neuromorphic computers, and biodegradable sensors. Our work involves new materials, scalable fabrication of electronic and photonic devices, and 3D heterogeneous integration, aiming to realize unconventional electronic systems.

Chip‑Scale Diamond MASER System – Theoretical Analysis, Component Design, and System Architecture Roadmap for Precision Time‑Keeping

Introduction and Background:

Diamond MASERs leverage the unique quantum properties of nitrogen‑vacancy (NV) centers in diamond to generate coherent microwave oscillations at room temperature. With diamond’s exceptional thermal conductivity, chemical stability, and long spin coherence times, these systems offer a promising alternative to conventional atomic clocks for precision time‑keeping. While continuous‑wave MASER operation in bulk diamond has been demonstrated, miniaturizing and integrating the technology onto a chip remains an open challenge. This project will focus on the theoretical analysis, component design, and proposal of an integrated system architecture and roadmap for a chip‑scale diamond MASER time‑keeping device. Full experimental development and system integration are beyond the scope of this Master’s project.

Project Objectives:

Theoretical Analysis and Modeling:

• Develop models for NV center spin dynamics, population inversion, and maser threshold conditions.
• Analyze effects of resonator Q‑factor, mode volume, thermal drift, and magnetic stability on frequency performance.
• Estimate potential time‑keeping metrics (e.g., Allan deviation) through simulation.

Component Design and Simulation:

• Optimize on-chip component design and assess performance parameters using simulation tools.

Integrated System Architecture and Roadmap:

• Propose a conceptual architecture that integrates the microwave resonator, optical pump, and control electronics.
• Develop a roadmap detailing key milestones and challenges for transitioning from theory to experimental prototype.
• Recommend potential fabrication and integration techniques based on current technology.

Expected Outcomes:

• Theoretical & Simulation Insights:
  A clear understanding of performance limits and design trade‑offs for chip‑scale diamond MASER time‑keeping.

• Component Design Protocols:
  Design and simulation of key components, including the microwave resonator and optical pump system.

• System Architecture Roadmap:
  A concise, actionable roadmap outlining future steps toward experimental realization and system integration.

Key References:

1. Breeze, T. D., et al. (2018). Continuous‑wave room‑temperature diamond maser. Nature, 555, 493–496.
2. Jin, L., et al. (2015). Proposal for a room‑temperature diamond maser based on nitrogen‑vacancy centers. Physical Review Letters, 115(23), 233601.
3. Zollitsch, C. W. et al. Maser threshold characterization by resonator Q-factor tuning. Commun. Phys. 6, 295 (2023).
4. Sherman, A., Buchbinder, L., Ding, S. & Blank, A. Performance analysis of diamond-based masers. J. Appl. Phys. 129, 144503 (2021).
5. Arroo, D. M., Alford, N. McN. & Breeze, J. D. Perspective on room-temperature solid-state masers. Appl. Phys. Lett. 119, 140502 (2021).

Interested? Please contact Ryoichi Ishihara r.ishihara@tudelft.nl or Salahuddin Nur <S.Nur@tudelft.nl>