Zobrazeno 1 - 10
of 248
pro vyhledávání: '"Montanaro, Ashley"'
Autor:
Montanaro, Ashley, Zhou, Leo
We present new advances in achieving exponential quantum speedups for solving optimization problems by low-depth quantum algorithms. Specifically, we focus on families of combinatorial optimization problems that exhibit symmetry and contain planted s
Externí odkaz:
http://arxiv.org/abs/2411.04979
QAC$^0$ is the class of constant-depth quantum circuits with polynomially many ancillary qubits, where Toffoli gates on arbitrarily many qubits are allowed. In this work, we show that the parity function cannot be computed in QAC$^0$, resolving a lon
Externí odkaz:
http://arxiv.org/abs/2411.00976
Autor:
Clinton, Laura, Cubitt, Toby S., Garcia-Patron, Raul, Montanaro, Ashley, Stanisic, Stasja, Stroeks, Maarten
In this work we demonstrate the use of adapted classical phase retrieval algorithms to perform control-free quantum phase estimation. We eliminate the costly controlled time evolution and Hadamard test commonly required to access the complex time-ser
Externí odkaz:
http://arxiv.org/abs/2410.21517
We prove a lower bound on the number of copies needed to test the property of a multipartite quantum state being product across some bipartition (i.e. not genuinely multipartite entangled), given the promise that the input state either has this prope
Externí odkaz:
http://arxiv.org/abs/2406.16827
Understanding quantum phase transitions in physical systems is fundamental to characterize their behaviour at small temperatures. Achieving this requires both accessing good approximations to the ground state and identifying order parameters to disti
Externí odkaz:
http://arxiv.org/abs/2405.08441
Autor:
Bosse, Jan Lukas, Childs, Andrew M., Derby, Charles, Gambetta, Filippo Maria, Montanaro, Ashley, Santos, Raul A.
In this work we propose an approach for implementing time-evolution of a quantum system using product formulas. The quantum algorithms we develop have provably better scaling (in terms of gate complexity and circuit depth) than a naive application of
Externí odkaz:
http://arxiv.org/abs/2403.08729
Autor:
Montanaro, Ashley, Shao, Changpeng
Let $A$ be an $s$-sparse Hermitian matrix, $f(x)$ be a univariate function, and $i, j$ be two indices. In this work, we investigate the query complexity of approximating $\bra{i} f(A) \ket{j}$. We show that for any continuous function $f(x):[-1,1]\ri
Externí odkaz:
http://arxiv.org/abs/2311.06999
Autor:
Montanaro, Ashley, Stanisic, Stasja
Variational Monte Carlo (VMC) methods are used to sample classically from distributions corresponding to quantum states which have an efficient classical description. VMC methods are based on performing a number of steps of a Markov chain starting wi
Externí odkaz:
http://arxiv.org/abs/2307.07719
Autor:
Wollmann, Sabine, Qiang, Xiaogang, Pallister, Sam, Montanaro, Ashley, Linden, Noah, Matthews, Jonathan C. F.
As a measure of the 'closeness' of two quantum states, fidelity plays a fundamental role in quantum information theory. Fidelity estimation protocols try to strike a balance between information gleaned from an experiment, and the efficiency of its im
Externí odkaz:
http://arxiv.org/abs/2306.01068
Quantum k-SAT (the problem of determining whether a k-local Hamiltonian is frustration-free) is known to be QMA_1-complete for k >= 3, and hence likely hard for quantum computers to solve. Building on a classical result of Alon and Shapira, we show t
Externí odkaz:
http://arxiv.org/abs/2301.10699