• Publications
  • Influence
Quantum supremacy using a programmable superconducting processor
TLDR
Quantum supremacy is demonstrated using a programmable superconducting processor known as Sycamore, taking approximately 200 seconds to sample one instance of a quantum circuit a million times, which would take a state-of-the-art supercomputer around ten thousand years to compute.
The second laws of quantum thermodynamics
TLDR
Here, it is found that for processes which are approximately cyclic, the second law for microscopic systems takes on a different form compared to the macroscopic scale, imposing not just one constraint on state transformations, but an entire family of constraints.
Local Random Quantum Circuits are Approximate Polynomial-Designs
We prove that local random quantum circuits acting on n qubits composed of O(t10n2) many nearest neighbor two-qubit gates form an approximate unitary t-design. Previously it was unknown whether
Resource theory of quantum states out of thermal equilibrium.
TLDR
It is shown that the free energy of thermodynamics emerges naturally from the resource theory of energy-preserving transformations, provided that a sublinear amount of coherent superposition over energy levels is available, a situation analogous to the sub linear amount of classical communication required for entanglement dilution.
Hypercontractivity, sum-of-squares proofs, and their applications
TLDR
Reductions between computing the 2->4 norm and computing the injective tensor norm of a tensor, a problem with connections to quantum information theory and the study of Khot's Unique Games Conjecture are shown.
Reversible Framework for Quantum Resource Theories.
TLDR
The general structure of QRTs is discussed, and it is shown that under a few assumptions, a QRT is asymptotically reversible if its set of allowed operations is maximal, that is, if the allowed operations are the set of all operations that do not generate (asymptotical) a resource.
Quantum Speed-Ups for Solving Semidefinite Programs
  • F. Brandão, K. Svore
  • Computer Science, Mathematics
    IEEE 58th Annual Symposium on Foundations of…
  • 1 October 2017
TLDR
It is proved the algorithm cannot be substantially improved (in terms of n and m) giving a quantum lower bound for solving semidefinite programs with constant s, R, r and δ.
Exponential Decay of Correlations Implies Area Law
TLDR
It is proved that a finite correlation length implies an area law for the entanglement entropy of quantum states defined on a line, and it is shown that 1D quantum states with exponential decay of correlations have an efficient classical approximate description as a matrix product state of polynomial bond dimension.
Determining eigenstates and thermal states on a quantum computer using quantum imaginary time evolution
TLDR
The quantum imaginary time evolution and Lanczos algorithms offer a resource-efficient way to compute ground or excited states of target Hamiltonians on quantum computers, and offers promise for quantum simulation on near-term noisy devices.
For Fixed Control Parameters the Quantum Approximate Optimization Algorithm's Objective Function Value Concentrates for Typical Instances
TLDR
Findings suggest ways to run the QAOA that reduce or eliminate the use of the outer loop optimization and may allow us to find good solutions with fewer calls to the quantum computer.
...
...