6 papers
Temporal nonlocality of a qudit resides in the input state, not the channel, and certifies temporal teleportation up to a fundamental limit
Karol Bartkiewicz, Patrycja Tulewicz
Correlations between two moments in time can be too strong for any classical explanation -- and, remarkably, this can happen for a single quantum system measured twice, with no sec…
Context-Verified, Error-Budget-Aware Decomposition Selection for Toffoli Networks
Karol Bartkiewicz, Patrycja Tulewicz
Two-qubit-gate error dominates the failure budget of near-term quantum circuits, so the decomposition chosen for each Toffoli (CCX) gate should minimize hardware two-qubit infideli…
Spin chirality across quantum state copies detects hidden entanglement
Patrycja Tulewicz, Karol Bartkiewicz, Franco Nori
Entanglement can hide in two fundamentally different ways. First, multi-copy correlations can carry information that no single-copy measurement on an unknown state is able to acces…
Resource-efficient quantum correlation measurements via multicopy neural network methods
Patrycja Tulewicz, Karol Bartkiewicz, Adam Miranowicz +1
Measuring complex properties in quantum systems, such as measures of quantum entanglement and Bell nonlocality, is inherently challenging. Traditional methods, like quantum state t…
Quantumness and its hierarchies in PT-symmetric down-conversion models
Jan PeÅina, Karol Bartkiewicz, Grzegorz Chimczak +4
We investigate the hierarchy of quantum correlations in a quadratic bosonic parity-time-symmetric system (PTSS) featuring distinct dissipation and amplification channels. The hiera…
Experimental Liouvillian exceptional points in a quantum system without Hamiltonian singularities
Shilan Abo, Patrycja Tulewicz, Karol Bartkiewicz +2
Hamiltonian exceptional points (HEPs) are spectral degeneracies of non-Hermitian Hamiltonians describing classical and semiclassical open systems with losses and/or gain. However,…