413 citations · 1.3k across the 36 of their papers we have counts for
38 papers
Permutation-invariant codes: a numerical study and qudit constructions
Liam J. Bond, Jiří Minář, Māris Ozols +2
We investigate Permutation-Invariant (PI) quantum error-correcting codes encoding a logical qudit of dimension in PI states using physical qudits of dimensi…
Sequential quantum processes with group symmetries
Dmitry Grinko, Satoshi Yoshida, Mio Murao +1
Symmetry plays a crucial role in the design and analysis of quantum protocols. This result shows a canonical circuit decomposition of a -invariant quantum comb for com…
High-dimensional quantum Schur transforms
Adam Burchardt, Jiani Fei, Dmitry Grinko +4
The quantum Schur transform has become a foundational quantum algorithm, yet even after two decades since the seminal 2005 paper by Bacon, Chuang, and Harrow (BCH), some aspects of…
Hidden shift problem for complex functions
Serge Adonsou, Peter Bruin, Maris Ozols +1
We study quantum algorithms for the hidden shift problem of complex scalar- and vector-valued functions on finite abelian groups. Given oracle access to a shifted function and the…
Entanglement recycling in two-step port-based teleportation
Piotr Kopszak, Dmitry Grinko, Adam Burchardt +3
A protocol involving the repetitive (twofold, to be precise) application of PBT protocol to the same resource is studied. The quantities characterizing the resulting protocol, so-c…
Trotter error and gate complexity of the SYK and sparse SYK models
Yiyuan Chen, Jonas Helsen, Maris Ozols
The Sachdev--Ye--Kitaev (SYK) model is a prominent model of strongly interacting fermions that serves as a toy model of quantum gravity and black hole physics. In this work, we stu…
Efficient quantum circuits for port-based teleportation
Dmitry Grinko, Adam Burchardt, Maris Ozols
Port-based teleportation (PBT) is a variant of quantum teleportation that, unlike the canonical protocol by Bennett et al., does not require a correction operation on the teleporte…
Gelfand-Tsetlin basis for partially transposed permutations, with applications to quantum information
Dmitry Grinko, Adam Burchardt, Maris Ozols
We study representation theory of the partially transposed permutation matrix algebra, a matrix representation of the diagrammatic walled Brauer algebra. This algebra plays a promi…
Monogamy of highly symmetric states
Rene Allerstorfer, Matthias Christandl, Dmitry Grinko +4
We investigate the extent to which two particles can be maximally entangled when they are also similarly entangled with other particles on a complete graph, focusing on Werner, iso…
Streaming quantum state purification
Andrew M. Childs, Honghao Fu, Debbie Leung +3
Quantum state purification is the task of recovering a nearly pure copy of an unknown pure quantum state using multiple noisy copies of the state. This basic task has applications…
Quantum policy gradient algorithms
Sofiene Jerbi, Arjan Cornelissen, Māris Ozols +1
Understanding the power and limitations of quantum access to data in machine learning tasks is primordial to assess the potential of quantum computing in artificial intelligence. P…
Quantum majority vote
Harry Buhrman, Noah Linden, Laura Mančinska +2
Majority vote is a basic method for amplifying correct outcomes that is widely used in computer science and beyond. While it can amplify the correctness of a quantum device with cl…
Parallel repetition of local simultaneous state discrimination
Llorenç Escolà-Farràs, Jaròn Has, Maris Ozols +2
Local simultaneous state discrimination (LSSD) is a recently introduced problem in quantum information processing. Its classical version is a non-local game played by non-communica…
Linear programming with unitary-equivariant constraints
Dmitry Grinko, Maris Ozols
Unitary equivariance is a natural symmetry that occurs in many contexts in physics and mathematics. Optimization problems with such symmetry can often be formulated as semidefinite…
Exact quantum query complexity of computing Hamming weight modulo powers of two and three
Arjan Cornelissen, Nikhil S. Mande, Maris Ozols +1
We study the problem of computing the Hamming weight of an -bit string modulo , for any positive integer whose only prime factors are 2 and 3. We show that the exa…
Local simultaneous state discrimination
Christian Majenz, Maris Ozols, Christian Schaffner +1
Quantum state discrimination is one of the most fundamental problems studied in quantum information theory. Applications range from channel coding to metrology and cryptography. In…
Quantum-access security of the Winternitz one-time signature scheme
Christian Majenz, Chanelle Matadah Manfouo, Maris Ozols
Quantum-access security, where an attacker is granted superposition access to secret-keyed functionalities, is a fundamental security model and its study has inspired results in po…
Span programs and quantum time complexity
Arjan Cornelissen, Stacey Jeffery, Maris Ozols +1
Span programs are an important model of quantum computation due to their tight correspondence with quantum query complexity. For any decision problem , the minimum complexity of…
Simulating Large Quantum Circuits on a Small Quantum Computer
Tianyi Peng, Aram Harrow, Maris Ozols +1
Limited quantum memory is one of the most important constraints for near-term quantum devices. Understanding whether a small quantum computer can simulate a larger quantum system,…
On Quantum Chosen-Ciphertext Attacks and Learning with Errors
Gorjan Alagic, Stacey Jeffery, Maris Ozols +1
Large-scale quantum computing is a significant threat to classical public-key cryptography. In strong "quantum access" security models, numerous symmetric-key cryptosystems are als…
Trading inverses for an irrep in the Solovay-Kitaev theorem
Adam Bouland, Maris Ozols
The Solovay-Kitaev theorem states that universal quantum gate sets can be exchanged with low overhead. More specifically, any gate on a fixed number of qudits can be simulated with…
The Need for Structure in Quantum LDPC Codes
Lior Eldar, Maris Ozols, Kevin F. Thompson
Existence of quantum low-density parity-check (LDPC) codes whose minimal distance scales linearly with the number of qubits is a major open problem in quantum information. Its prac…
Hamiltonian Simulation with Optimal Sample Complexity
Shelby Kimmel, Cedric Yen-Yu Lin, Guang Hao Low +2
We investigate the sample complexity of Hamiltonian simulation: how many copies of an unknown quantum state are required to simulate a Hamiltonian encoded by the density matrix of…
The Complexity of Translationally-Invariant Spin Chains with Low Local Dimension
Johannes Bausch, Toby Cubitt, Maris Ozols
We prove that estimating the ground state energy of a translationally-invariant, nearest-neighbour Hamiltonian on a 1D spin chain is QMAEXP-complete, even for systems of low local…