Research

Entanglement is one of the most remarkable features of quantum physics: quantum systems can share correlations that have no classical counterpart, enabling new ways of communicating and processing information. But how can we determine how much useful entanglement is present, and how can we recover it when it is noisy or imperfect? My research addresses these questions through device-independent certification of distillable entanglement and the development of entanglement distillation protocols adapted to physical platforms. I am also interested in the fundamental relationship between entanglement and secrecy.

Selected papers:

• Rotem Arnon-Friedman and Jean-Daniel Bancal. "Device-independent certification of one-shot distillable entanglement." New Journal of Physics 21, no. 3: 033010 (2019)

• Rotem Arnon-Friedman and Felix Leditzky. "Upper bounds on device-independent quantum key distribution rates and a revised Peres conjecture." IEEE Transactions on Information Theory 67, no. 10: 6606-6618 (2021)

• Thomas A. Hahn, Ryan White, Hannes Bernien, and Rotem Arnon. "Deterministic high-rate entanglement distillation with neutral atom arrays." arXiv preprint arXiv:2503.00445 (2025)

• Shoham Jacoby, Rotem Arnon and Serge Rosenblum. "Hardware-Efficient Entanglement Distillation Using Bosonic Systems". arXiv preprint arXiv:2503.09700 (2025)

Can we guarantee that a secret remains private even when we cannot fully trust the devices used to generate it? Quantum cryptography offers remarkable possibilities for establishing security based on the laws of quantum physics rather than assumptions about an adversary's computational power. My research focuses on developing and proving the security of quantum key distribution and randomness generation protocols, particularly in device-independent settings, where security is established through observed statistics rather than a detailed model of the devices. A central tool in my work is entropy accumulation, which enables quantitative security guarantees against general quantum attacks in realistic, finite-size scenarios. I also investigate randomness amplification and certification under different physical and computational assumptions, as well as the achievable performance of these protocols with realistic quantum hardware.

Selected papers:

• Rotem Arnon-Friedman, Frédéric Dupuis, Omar Fawzi, Renato Renner, and Thomas Vidick. "Practical device-independent quantum cryptography via entropy accumulation." Nature communications 9, no. 1: 459 (2018)

• Max Kessler, and Rotem Arnon-Friedman. "Device-independent randomness amplification and privatization." IEEE Journal on Selected Areas in Information Theory 1, no. 2: 568-584 (2020)

• Ilya Merkulov, and Rotem Arnon. "Entropy accumulation under post-quantum cryptographic assumptions." Entropy 27, no. 8: 772 (2025)

• Thomas A Hahn, Efrat Gerchkovitz, Ester Yehuda, and Rotem Arnon. "Certified Randomness Generation against Quantum
  Adversaries via Energy Constraints." arXiv preprint arXiv:2610.05766 (2026)

What is the value of a quantum resource if exploiting it requires an infeasible amount of computation? While quantum information theory traditionally studies what is possible in principle, computational limitations can fundamentally change which tasks are achievable and which resources are useful. My research aims to develop a computational theory of quantum information, incorporating computational complexity into the definitions and operational interpretations of fundamental quantities such as entanglement and entropy. This includes computational notions of entanglement cost and distillable entanglement, as well as computational analogues of quantum min- and max-entropy. I am particularly interested in the connections between these quantities, quantum cryptography, pseudorandomness, and the distinction between information that exists in a quantum system and information that can be efficiently accessed.

Selected papers:

• Rotem Arnon, Zvika Brakerski, and Thomas Vidick. "Computational entanglement theory." arXiv preprint arXiv:2310.02783 (2023)

• Ilya Merkulov, and Rotem Arnon. "Entropy accumulation under post-quantum cryptographic assumptions." Entropy 27, no. 8: 772 (2025)

• Ilya Merkulov and Rotem Arnon. "Computational Bell Inequalities." New Journal of Physics 28.8: 084502 (2026)

• Noam Avidan and Rotem Arnon. "Quantum Computational Unpredictability Entropy and Quantum Leakage Resilience." IEEE Transactions on Information Theory, vol. 72, no. 5, pp. 3129-3155 (2026)

• Noam Avidan, Thomas A. Hahn, Joseph M. Renes, and Rotem Arnon. "Fully Quantum Computational Entropies." 17th Innovations in Theoretical Computer Science Conference (ITCS 2026). Full version: arXiv:2506.14068 (2026)

Two distant quantum systems can produce correlations that cannot be explained by any local classical theory, challenging our understanding of how the physical world works. These non-local correlations are not only fascinating from a foundational perspective; they also provide a powerful tool for certifying quantum behaviour without trusting the underlying devices. My research investigates the mathematical structure of non-local correlations and their applications to quantum information processing. This includes the study of non-local games, the robustness of Bell inequality violations to noise and particle loss, and the development of computational Bell inequalities, which connect quantum non-locality with computational assumptions and single-device verification. More broadly, I am interested in understanding what quantum correlations allow us to certify and how they can be used in cryptographic applications.

Selected papers:

• Rotem Arnon-Friedman, Renato Renner, and Thomas Vidick. "Non-signaling parallel repetition using de Finetti reductions." IEEE Transactions on Information Theory 62, no. 3: 1440-1457 (2016)

• Shahar Silberstein, and Rotem Arnon-Friedman. "Robustness of Bell violation of graph states to qubit loss." Physical Review Research 5, no. 4: 04309 (2023)

• Ilya Merkulov and Rotem Arnon. "Computational Bell Inequalities." New Journal of Physics 28.8: 084502 (2026)