Quantum 9, 1619 (2025). https://doi.org/10.22331/q-2025-02-04-1619 The quantum Fisher information (QFI) bounds the sensitivity of a quantum measurement, heralding the conditions for quantum advantages when compared with classical strategies. Here, we calculate analytical expressions for the […]
Quantum 9, 1618 (2025). https://doi.org/10.22331/q-2025-01-30-1618 Unlike the surface code, quantum low-density parity-check (QLDPC) codes can have a finite encoding rate, potentially lowering the error correction overhead. However, finite-rate QLDPC codes have nonlocal stabilizers, making it […]
Quantum 9, 1617 (2025). https://doi.org/10.22331/q-2025-01-30-1617 Variational quantum algorithms (VQAs) hold much promise but face the challenge of exponentially small gradients. Unmitigated, this barren plateau (BP) phenomenon leads to an exponential training overhead for VQAs. Perhaps […]
Quantum 9, 1616 (2025). https://doi.org/10.22331/q-2025-01-30-1616 The Page-Wootters formalism is a proposal for reconciling the background-dependent, quantum-mechanical notion of time with the background independence of general relativity. However, the physical meaning of this framework remains debated. […]
Quantum 9, 1615 (2025). https://doi.org/10.22331/q-2025-01-30-1615 Dual-unitary quantum circuits have recently attracted attention as an analytically tractable model of many-body quantum dynamics. Consisting of a 1+1D lattice of 2-qudit gates arranged in a ‘brickwork’ pattern, these […]
Quantum 9, 1614 (2025). https://doi.org/10.22331/q-2025-01-28-1614 Considering a general microscopic model for a quantum measuring apparatus comprising a quantum probe coupled to a thermal bath, we analyze the energetic resources necessary for the realization of a […]
Quantum 9, 1613 (2025). https://doi.org/10.22331/q-2025-01-28-1613 Connecting multiple processors via quantum interconnect technologies could help overcome scalability issues in single-processor quantum computers. Transmission via these interconnects can be performed more efficiently using quantum multiplexing, where information […]
Quantum 9, 1612 (2025). https://doi.org/10.22331/q-2025-01-28-1612 We provide a systematic framework for constructing generic models of nonequilibrium quantum dynamics with a target stationary (mixed) state. Our framework identifies (almost) all combinations of Hamiltonian and dissipative dynamics […]
Quantum 9, 1611 (2025). https://doi.org/10.22331/q-2025-01-27-1611 The design of quantum protocols for secure key generation poses many challenges: On the one hand, they need to be practical concerning experimental realisations. On the other hand, their theoretical […]
Quantum 9, 1610 (2025). https://doi.org/10.22331/q-2025-01-27-1610 Group field theory posits that spacetime is emergent and is hence defined without any background notion of space or time; dynamical questions are formulated in relational terms, in particular using […]
Recent Comments