Reduction of the asymptotic prefactors for an optimally bounded quantum state preparation algorithm

Near-Lower-Bound Approximate Quantum State Preparation with Hardware-Efficient Circuits

An efficient Hamiltonian-based quantum algorithm for characters of the symmetric group

Consider a quantum state vector proportional to any given column of the character table of the symmetric group ($S_n$), corresponding to a superposition over the irreps weighted by the character values. It was recently argued that sampling from this state is classically hard under reasonable complexity-theoretic assump...

A 12-CNOT Double Qubit Excitation Gate

This work presented, to the best of the knowledge, the first reported 12-CNOT decomposition of the double qubit excitation operator, and compared the new circuit with the previous SOTA 13-CNOT circuits in 4 different metrics.

Fast Cliffords When Your Quantum Memory Is Full

Additional qubits can reduce the depth of a quantum circuit by providing workspace for parallel computation, but standard constructions assume that this workspace is initialized in a known state. In this work we study catalytic implementations, i.e. asking whether dirty qubits can instead be used provided that their jo...

Ultra-Precise Quantum Projective Designs in Constant Depth

The results show that precise Haar-like statistics can emerge from sparse commuting dynamics with remarkably low quantum resources, with applications to randomized characterization, quantum metrology, quantum algorithms, and many-body physics.

A quantum double-bracket algorithm for imaginary-time evolution with exponentially shorter depth

Imaginary-time evolution (ITE) is a widely used technique for preparing the ground state of a target Hamiltonian. Building on the recently proposed framework of Double-Bracket quantum ITE (DB-QITE), we introduce a probabilistic variant (PDBQITE) that achieves an exponential reduction in circuit depth. Our algorithm req...