About Me

I am a postdoc researcher at the University of Sydney. My host is Prof. Qiang Tang. My research focuses on applied cryptography, with their applications in blockchains. I obtained the Ph.D. degree in Computer Science and Engineering department at HKUST. I was fortunate to be advised by Prof. Dimitris Papadopoulos during my PhD.

Selected Publications (Full list)

Morphic Accumulators and Applications: Optimal Range Proofs, Polynomial Commitments, and (Linkable) Ring Signatures
Dimitris Papadopoulos, Qiang Tang, Jiajun Xin
Crypto 2026
[Paper] [Slides] [Talk]
Gryphes: Hybrid Proofs for Modular SNARKs with Applications to zkRollups
Jiajun Xin, Samuel Cheung On Tin, Christodoulos Pappas, Yongjin Huang, Dimitris Papadopoulos
PoPETs 2026
[Paper] [Code]
"Check-Before-you-Solve": Verifiable Time-lock Puzzles
Jiajun Xin, Dimitris Papadopoulos
IEEE Symposium on Security and Privacy (SP) 2025
[Paper] [Code] [Talk]
Notus: Dynamic Proofs of Liabilities from Zero-knowledge RSA Accumulators
Jiajun Xin, Arman Haghighi, Xiangan Tian, Dimitris Papadopoulos
USENIX Security Symposium 2024
[Paper] [Code] [Artifact] [Talk]
An Incentive-Compatible Mechanism for Decentralized Storage Network
Iman Vakilinia, Weihong Wang, Jiajun Xin
IEEE Transactions on Network Science and Engineering 2023
[Paper] [Code]

Education

Ph.D. in Computer Science and Engineering
Hong Kong University of Science and Technology
Aug 2020 - Aug 2025
Advisor: Prof. Dimitris Papadopoulos
Master in Computer Science and Engineering
University of Nevada, Reno
Sep 2015 - Dec 2017
Bachelor in Network Engineering
Dalian University of Technology
Aug 2011 - Jun 2015

Work Experience

Postdoc Researcher
University of Sydney
Host: Prof. Qiang Tang
Software Engineer
Huawei
Blockchain Engineer
Xunlei

Academic Service

Contact

Email: jiajun.xin@sydney.edu.au