Tanay Roy, Xinyuan You, David van Zanten, Francesco Crisa, Sabrina Garattoni, Shaojiang Zhu, Anna Grassellino, Alexander Romanenko • Published: 2026-02-11
Transmon qubits are a cornerstone of modern superconducting quantum computing platforms. Temporal fluctuations of energy relaxation in these qubits are widely attributed to microscopic two-level systems (TLSs) in device dielectrics and interfaces, yet isolating individual defects typically relies on tuning the qubit or the TLS into resonance. We demonstrate a novel spectroscopy method for fixed-fr...
Jan A. Krzywda, Yuta Matsumoto, Maxim De Smet, Larysa Tryputen, Sander L. de Snoo, Sergey V. Amitonov, Evert van Nieuwenburg, Giordano Scappucci, Lieven M. K. Vandersypen • Published: 2026-02-09
Mobile spin qubit architectures promise flexible connectivity for efficient quantum error correction and relaxed device layout constraints, but their viability rests on preserving spin coherence during transport. While shuttling transforms spatial disorder into time-dependent noise, its net impact on spin coherence remains an open question. Here we demonstrate systematic noise mitigation during sp...
Emil Grovn, Matias Bundgaard-Nielsen, Jesper Mørk, Dirk Englund, Mikkel Heuck • Published: 2026-02-11
A fundamental challenge in photonics-based deterministic quantum information processing is to realize key transformations on time scales shorter than those of detrimental decoherence and loss mechanisms. This challenge has been addressed through device-focused approaches that aim to increase nonlinear interactions relative to decoherence rates. In this work, we adopt a complementary architecture-f...
Harish Karthikeyan, Yue Guo, Leo de Castro, Antigoni Polychroniadou, Udari Madhushani Sehwag, Leo Ardon, Sumitra Ganesh, Manuela Veloso • Published: 2025-12-08
As AI agents increasingly operate in complex environments, ensuring reliable, context-aware privacy is critical for regulatory compliance. Traditional access controls are insufficient because privacy risks often arise after access is granted; agents may inadvertently compromise privacy during reasoning by messaging humans, leaking context to peers, or executing unsafe tool calls. Existing approach...
Yi-Neng Zhou, Robin Löwenberg, Julian Sonner • Published: 2025-04-07
We present efficient and practical protocols to measure the second Rényi entropy (RE), whose exponential is known as the purity. We achieve this by establishing a direct connection to a Loschmidt echo (LE) type measurement sequence, applicable to quantum many-body systems. Notably, our approach does not rely on random-noise averaging, a feature that can be extended to protocols to measure out-of-t...
Koji Yamaguchi, Leon Rullkötter, Ibrahim Shehzad, Sean J. Wagner, Christian Tutschku, Achim Kempf • Published: 2026-02-11
The no-cloning theorem forbids the creation of identical copies of qubits, thereby imposing strong limitations on quantum technologies. A recently-proposed protocol, encrypted cloning, showed, however, that the creation of perfect clones is theoretically possible - if the clones are simultaneously encrypted with a single-use decryption key. It has remained an open question, however, whether encryp...
Abdelrhman Shaheen, Anas Badr, Ali Abohendy, Hatem Alsaadawy, Nadine Alsayad, Ehab H. El-Shazly • Published: 2025-02-14
Reinforcement Learning (RL) has been widely used in many applications, particularly in gaming, which serves as an excellent training ground for AI models. Google DeepMind has pioneered innovations in this field, employing reinforcement learning algorithms, including model-based, model-free, and deep Q-network approaches, to create advanced AI models such as AlphaGo, AlphaGo Zero, and MuZero. Alpha...
Ashish Kumar Patra, Anurag K. S. V., Sai Shankar P., Ruchika Bhat, Raghavendra V., Rahul Maitra, Jaiganesh G • Published: 2025-11-27
The accurate treatment of electron correlation in extended molecular systems remains computationally challenging using classical electronic structure methods. Hybrid quantum-classical algorithms offer a potential route to overcome these limitations; however, their practical deployment on existing quantum computers requires strategies that both reduce problem size and mitigate hardware noise. In th...