33 citations · 55 across the 9 of their papers we have counts for
9 papers
Necessary and Sufficient Conditions for Local Unitary Equivalence of Multi-qubit States
A. M. Martins
We derive necessary and sufficient conditions for the LU-equivalence of two general (pure or mixed) -qubit states as well as we determine the local unitary operators connecting…
Comment on: Local Unitary Equivalence of Multipartite Pure Qubits States
A. M. Martins
A Comment on the Letter by B. Kraus {\it Phys. Rev. Lett.}{\bf 104}, 020504 (2010).
Invariance of reduced density matrices under Local Unitary operations
A. M. Martins
We derive necessary and sufficient conditions for local unitary (LU) operators to leave invariant the set of 1-qubit reduced density matrices of a multi-qubit state. LU operators w…
Macroscopic entanglement between wave-packets at finite temperature
Ana M. Martins
We investigate entanglement between collective operators of two wave-packets of finite spectral bandwidth, in two different approximations of the Multimode Parametric-Down Conversi…
Entanglement in parametric down-conversion with phase mismatch at finite temperature
Ana M. Martins
In this work the degree of entanglement of two-photon states generated by parametric-down conversion with a phase mismatch is computed in terms of the temperature of the nonlinear…
Influence of the spectral bandwidth in the entanglement of a nondegenerate parametric amplifier
Ana M. Martins
We propose a simple model for the nondegenerate parametric inter- action that takes into account the finite spectral bandwidth of the pump wave. The Heisenberg equations of motion…
Dimension minimization of a quantum automaton
A. M. Martins
A new model of a Quantum Automaton (QA), working with qubits is proposed. The quantum states of the automaton can be pure or mixed and are represented by density operators. This is…
Quantum Logic with a Single Trapped Electron
S. Mancini, A. M. Martins, P. Tombesi
We propose the use of a trapped electron to implement quantum logic operations. The fundamental controlled-NOT gate is shown to be feasible. The two quantum bits are stored in the…
Electron-radiation interaction in a Penning trap: beyond the dipole approximation
Ana M. Martins, Stefano Mancini, Paolo Tombesi
We investigate the physics of a single trapped electron interacting with a radiation field without the dipole approximation. This gives new physical insights in the so-called geoni…