48 citations · 50 across the 9 of their papers we have counts for
12 papers
Scalable Passive QRAM
Siddhartha Jain, Alexander M. Dalzell, Connor T. Hann
We present a blueprint for implementing the physical QRAM operation in a scalable, passive manner, proving its feasibility in principle. Our construction is passive because for an…
Solving Sparse SDPs in Sublinear Time: A Classical Algorithm Inspired by the Quantum OR Lemma
Fernando G. S. L. Brandão, Alexander M. Dalzell, András Gilyén +1
We give the first sublinear-time classical solvers for sparse semidefinite programs in the bounded-radius regime, without low-rank assumptions or Frobenius norm dependence on the c…
Quantum oblique eigenprojection
Alexander M. Dalzell, Yuan Su
Every square matrix decomposes its underlying Hilbert space into generalized, nonorthogonal eigensubspaces. We show that a quantum computer can perform such an oblique eigenproject…
Suppressing errors in analog logical rotation gates via balanced fusion
Sam McArdle, Alexander M. Dalzell, Fernando G. S. L. Brandão
There have been a number of recent proposals to use analog logical rotations in early fault-tolerant quantum algorithms. Existing proposals implement a logical rotation by angle $ϕ…
Faster quantum linear system solver beyond the condition number
Alexander M. Dalzell, Jianqiang Li, Yuan Su
The spectral condition number is a widely adopted measure of worst-case cost for quantum linear system solvers. Yet it can significantly overestimate the actual runtime for a typic…
Constant Factor Analysis of Optimal Quantum Linear Solvers in Practice
Pedro C. S. Costa, Alexander M. Dalzell, Dong An +1
Optimal quantum linear equation solvers provide complexity , where is the condition number and is the allowable error. The optimal solver using a discrete ad…
The Fast for the Curious: How to accelerate fault-tolerant quantum applications
Sam McArdle, Alexander M. Dalzell, Aleksander Kubica +1
We evaluate strategies for reducing the run time of fault-tolerant quantum computations, targeting practical utility in scientific or industrial workflows. Delivering a technology…
Quantum and classical algorithms for SOCP based on the multiplicative weights update method
M. Isabel Franco Garrido, Alexander M. Dalzell, Sam McArdle
We give classical and quantum algorithms for approximately solving second-order cone programs (SOCPs) based on the multiplicative weights (MW) update method. Our approach follows t…
A distillation-teleportation protocol for fault-tolerant QRAM
Alexander M. Dalzell, András Gilyén, Connor T. Hann +5
We present a protocol for fault-tolerantly implementing the logical quantum random access memory (QRAM) operation, given access to a specialized, noisy QRAM device. For coherently…
Optimizing random local Hamiltonians by dissipation
Joao Basso, Chi-Fang Chen, Alexander M. Dalzell
A central challenge in quantum simulation is to prepare low-energy states of strongly interacting many-body systems. In this work, we study the problem of preparing a quantum state…
A shortcut to an optimal quantum linear system solver
Alexander M. Dalzell
Given a linear system of equations , quantum linear system solvers (QLSSs) approximately prepare a quantum state for which…
Quantum algorithms: A survey of applications and end-to-end complexities
Alexander M. Dalzell, Sam McArdle, Mario Berta +10
The anticipated applications of quantum computers span across science and industry, ranging from quantum chemistry and many-body physics to optimization, finance, and machine learn…