14 citations · 24 across the 13 of their papers we have counts for
17 papers
Single-Shot Error Correction at Optimal Spacetime Cost
Kishor Bharti, Tobias Haug, Derek Khu +1
Recent work established that, for independent erasures, storing logical qubits for time steps with error at most requires a spacetime cost of $Ω(S(K+\log(S/\v…
High-Rate Quantum Codes with Proven Distance and Low-Weight Measurements
Kishor Bharti, Tobias Haug, Runzhou Tao +1
We study a family of quantum subsystem codes defined on rectangular coordinate grids of any dimension, with even side lengths of at least four. The directly measured operators act…
Function-like pseudorandom unitaries generate pseudorandom quantum processes
Zitai Xu, Rahul Arvind, Kishor Bharti +5
Haar-random unitaries provide a canonical model of generic random quantum evolution, but they typically have exponential description and circuit complexity. Although pseudorandom u…
Syndrome measurements enable deterministic fault-tolerant gates
Kishor Bharti, Tobias Haug, Andrew Tanggara
Non-Clifford gates are essential for universal quantum computation, yet implementing them fault-tolerantly remains a central challenge for stabilizer codes. Here, we show how a syn…
Fault-tolerant quantum computation cannot be achieved with constant spacetime overhead
Kishor Bharti, Tobias Haug, Andrew Tanggara
The threshold theorem states that quantum computations can be made reliable below a physical error threshold, at the cost of additional physical qubits and circuit depth. Recent wo…
Two-copy nondistillability of Werner states: sharp partial-trace inequalities and finite-copy extensions
Kishor Bharti, Rishikesh Gajjala, Tobias Haug
We solve the two-copy distillability problem for Werner states in every local dimension. Our main matrix result is a sharp, dimension-free inequality: for every rank-at-most-two op…
Quantum error correction and fault tolerance: A comprehensive tutorial
Daniel J. Spencer, Shubham P. Jain, Andrew Tanggara +4
Noise is one of the central obstacles to building useful quantum computers, and quantum error correction (QEC) provides the framework for protecting quantum information against it.…
Hierarchical quantum decoders
Nirupam Basak, Ankith Mohan, Andrew Tanggara +3
Decoders are a critical component of fault-tolerant quantum computing. They must identify errors based on syndrome measurements to correct quantum states. While finding the optimal…
Quantum Cubature Codes
Yaoling Yang, Andrew Tanggara, Tobias Haug +1
Bosonic codes utilize the infinite-dimensional Hilbert space of harmonic oscillators to encode quantum information, offering a hardware-efficient approach to quantum error correcti…
Qudit low-density parity-check codes
Daniel J. Spencer, Andrew Tanggara, Tobias Haug +2
Qudits offer significant advantages over qubit-based architectures, including more efficient gate compilation, reduced resource requirements, improved error-correction primitives,…
Quantum heuristics for linear optimization over large separable operators
Ankith Mohan, Tobias Haug, Kishor Bharti +1
Optimizing over separable quantum objects is challenging for two key reasons: determining separability is NP-hard, and the dimensionality of the problem grows exponentially with th…
Quantum Error Correction in Adversarial Regimes
Rahul Arvind, Nikhil Bansal, Dax Enshan Koh +2
In adversarial settings, where attackers can deliberately and strategically corrupt quantum data, standard quantum error correction reaches its limits. It can only correct up to ha…
Pseudorandom quantum authentication
Tobias Haug, Nikhil Bansal, Wai-Keong Mok +2
We introduce the pseudorandom quantum authentication scheme (PQAS), an efficient method for encrypting quantum states that relies solely on the existence of pseudorandom unitaries…
MaxSAT decoders for arbitrary CSS codes
Mohammadreza Noormandipour, Tobias Haug
Quantum error correction (QEC) is essential for operating quantum computers in the presence of noise. Here, we accurately decode arbitrary Calderbank-Shor-Steane (CSS) codes via th…
Optimal Conversion from Classical to Quantum Randomness via Quantum Chaos
Wai-Keong Mok, Tobias Haug, Adam L. Shaw +2
Quantum many-body systems provide a unique platform for exploring the rich interplay between chaos, randomness, and complexity. In a recently proposed paradigm known as deep therma…
Pseudorandom density matrices
Nikhil Bansal, Wai-Keong Mok, Kishor Bharti +2
Pseudorandom states (PRSs) are state ensembles that cannot be efficiently distinguished from Haar random states. However, the definition of PRSs has been limited to pure states and…
Multivariate Bicycle Codes
Lukas Voss, Sim Jian Xian, Tobias Haug +1
Quantum error correction suppresses noise in quantum systems to allow for high-precision computations. In this work, we introduce Multivariate Bicycle (MB) Quantum Low-Density Pari…