1.2k citations · 3.4k across the 33 of their papers we have counts for
36 papers
Fault-tolerant resource estimation for ground-state preparation via Lindblad simulation
Marius Bothe, Patrick Schoepf, Nick S. Blunt
Recent advances in algorithms for simulating Lindblad dynamics have clarified their theoretical potential for state preparation, but their practicality in the early fault-tolerant…
More efficient Clifford+T synthesis for small-angle rotations and application to Trotterization
Marius Bothe, Christoph Sünderhauf, Michael J. Witham +2
Clifford+T synthesis of rotation gates is an important routine in fault-tolerant quantum compilation. While Clifford+T synthesis is scalable, it has a high overhead of tens of T ga…
Quantum simulation of nanographenes and Trotter error cancellation
Andreas Juul Bay-Smidt, Nina Glaser, Marcel D. Fabian +3
Fault-tolerant quantum computing is a promising tool for simulating molecules and materials, but frequently-considered applications require substantial resources, and the gap betwe…
A Monte Carlo approach to bound Trotter error
Nick S. Blunt, Aleksei V. Ivanov, Andreas Juul Bay-Smidt
Trotter product formulas are a natural and powerful approach to perform quantum simulation. However, the error analysis of product formulas is challenging, and their cost is often…
Fault-tolerant quantum simulation of generalized Hubbard models
Andreas Juul Bay-Smidt, Frederik Ravn Klausen, Christoph Sünderhauf +3
Quantum simulations of strongly interacting fermionic systems, such as those described by the Hubbard model, are promising candidates for useful early fault-tolerant quantum comput…
A quantum computing approach to fixed-node Monte Carlo using classical shadows
Nick S. Blunt, Laura Caune, Javiera Quiroz-Fernandez
Quantum Monte Carlo (QMC) methods are powerful approaches for solving electronic structure problems. Although they often provide high-accuracy solutions, the precision of most QMC…
Demonstrating real-time and low-latency quantum error correction with superconducting qubits
Laura Caune, Luka Skoric, Nick S. Blunt +22
Quantum error correction (QEC) will be essential to achieve the accuracy needed for quantum computers to realise their full potential. The field has seen promising progress with de…
The Electronic Structure of the Hydrogen Molecule: A Tutorial Exercise in Classical and Quantum Computation
Vincent Graves, Christoph Sünderhauf, Nick S. Blunt +2
In this educational paper, we will discuss calculations on the hydrogen molecule both on classical and quantum computers. In the former case, we will discuss the calculation of mol…
Compilation of a simple chemistry application to quantum error correction primitives
Nick S. Blunt, György P. Gehér, Alexandra E. Moylett
A number of exciting recent results have been seen in the field of quantum error correction. These include initial demonstrations of error correction on current quantum hardware, a…
Statistical phase estimation and error mitigation on a superconducting quantum processor
Nick S. Blunt, Laura Caune, Róbert Izsák +2
Quantum phase estimation (QPE) is a key quantum algorithm, which has been widely studied as a method to perform chemistry and solid-state calculations on future fault-tolerant quan…
Measuring Electron Correlation. The Impact of Symmetry and Orbital Transformations
Róbert Izsák, Aleksei V Ivanov, Nick S. Blunt +2
In this perspective, the various measures of electron correlation used in wavefunction theory, density functional theory and quantum information theory are briefly reviewed. We the…
A perspective on the current state-of-the-art of quantum computing for drug discovery applications
Nick S. Blunt, Joan Camps, Ophelia Crawford +9
Computational chemistry is an essential tool in the pharmaceutical industry. Quantum computing is a fast evolving technology that promises to completely shift the computational cap…
Quantum Computing in Pharma: A Multilayer Embedding Approach for Near Future Applications
Robert Izsak, Christoph Riplinger, Nick S. Blunt +6
Quantum computers are special purpose machines that are expected to be particularly useful in simulating strongly correlated chemical systems. The quantum computer excels at treati…
Demonstration of multi-qubit entanglement and algorithms on a programmable neutral atom quantum computer
T. M. Graham, Y. Song, J. Scott +22
Gate model quantum computers promise to solve currently intractable computational problems if they can be operated at scale with long coherence times and high fidelity logic. Neutr…
Fixed and partial-node approximations in Slater determinant space for molecules
Nick S. Blunt
We present a study of fixed and partial-node approximations in Slater determinant basis sets, using full configuration interaction quantum Monte Carlo (FCIQMC) to perform sampling.…
Efficient multireference perturbation theory without high-order reduced density matrices
Nick S. Blunt, Ankit Mahajan, Sandeep Sharma
We present a stochastic approach to perform strongly contracted n-electron valence state perturbation theory (SC-NEVPT), which only requires one- and two-body reduced density matri…
NECI: N-Electron Configuration Interaction with emphasis on state-of-the-art stochastic methods
Kai Guther, Robert J. Anderson, Nick S. Blunt +22
We present NECI, a state-of-the-art implementation of the Full Configuration Interaction Quantum Monte Carlo algorithm, a method based on a stochastic application of the Hamiltonia…
Recent developments in the PySCF program package
Qiming Sun, Xing Zhang, Samragni Banerjee +46
PYSCF is a Python-based general-purpose electronic structure platform that both supports first-principles simulations of molecules and solids, as well as accelerates the developmen…
Multireference configuration interaction and perturbation theory without reduced density matrices
Ankit Mahajan, Nick S. Blunt, Iliya Sabzevari +1
The computationally expensive evaluation and storage of high-rank reduced density matrices (RDMs) has been the bottleneck in the calculation of dynamic correlation for multireferen…
A hybrid approach to extending selected configuration interaction and full configuration interaction quantum Monte Carlo
Nick S. Blunt
We present an approach to combining selected configuration interaction (SCI) and initiator full configuration interaction quantum Monte Carlo (i-FCIQMC). In the current i-FCIQMC sc…
Preconditioning and perturbative estimators in full configuration interaction quantum Monte Carlo
Nick S. Blunt, Alex J. W. Thom, Charles J. C. Scott
We propose the use of preconditioning in FCIQMC which, in combination with perturbative estimators, greatly increases the efficiency of the algorithm. The use of preconditioning al…
The HANDE-QMC project: open-source stochastic quantum chemistry from the ground state up
James S. Spencer, Nick S. Blunt, Seonghoon Choi +15
Building on the success of Quantum Monte Carlo techniques such as diffusion Monte Carlo, alternative stochastic approaches to solve electronic structure problems have emerged over…
Excited-state diffusion Monte Carlo calculations: a simple and efficient two-determinant ansatz
Nick S. Blunt, Eric Neuscamman
We perform excited-state variational Monte Carlo and diffusion Monte Carlo calculations using a simple and efficient wave function ansatz. This ansatz follows the recent variation-…
Non-linear biases, stochastically-sampled effective Hamiltonians and spectral functions in quantum Monte Carlo methods
Nick S. Blunt, Ali Alavi, George H. Booth
In this article we study examples of systematic biases that can occur in quantum Monte Carlo methods due to the accumulation of non-linear expectation values, and approaches by whi…