702 citations · 1.3k across the 29 of their papers we have counts for
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The Complexity of Translationally Invariant Problems beyond Ground State Energies
James D. Watson, Johannes Bausch, Sevag Gharibian
It is known that three fundamental questions regarding local Hamiltonians -- approximating the ground state energy (the Local Hamiltonian problem), simulating local measurements on…
Fast Black-Box Quantum State Preparation
Johannes Bausch
Quantum state preparation is an important ingredient for other higher-level quantum algorithms, such as Hamiltonian simulation, or for loading distributions into a quantum device t…
Recurrent Quantum Neural Networks
Johannes Bausch
Recurrent neural networks are the foundation of many sequence-to-sequence models in machine learning, such as machine translation and speech synthesis. In contrast, applied quantum…
Translationally-Invariant Universal Quantum Hamiltonians in 1D
Tamara Kohler, Stephen Piddock, Johannes Bausch +1
Recent work has characterised rigorously what it means for one quantum system to simulate another, and demonstrated the existence of universal Hamiltonians -- simple spin lattice H…
Mitigating Errors in Local Fermionic Encodings
Johannes Bausch, Toby Cubitt, Charles Derby +1
Quantum simulations of fermionic many-body systems crucially rely on mappings from indistinguishable fermions to distinguishable qubits. The non-local structure of fermionic Fock s…
A Compact Fermion to Qubit Mapping
Charles Derby, Joel Klassen
Mappings between fermions and qubits are valuable constructions in physics. To date only a handful exist. In addition to revealing dualities between fermionic and spin systems, suc…
Hamiltonian Simulation Algorithms for Near-Term Quantum Hardware
Laura Clinton, Johannes Bausch, Toby Cubitt
The quantum circuit model is the de-facto way of designing quantum algorithms. Yet any level of abstraction away from the underlying hardware incurs overhead. In the era of near-te…
Universal Translationally-Invariant Hamiltonians
Stephen Piddock, Johannes Bausch
In this work we extend the notion of universal quantum Hamiltonians to the setting of translationally-invariant systems. We present a construction that allows a two-dimensional spi…