Optical resonance between the initially occupied excited atomic state and some lower lying state is shown to be a suppressor of two-photon ionization from this excited state via near-threshold Rydberg states because of Rabi oscillations between the resonantly coupled states.
A protocol for teleporting two qudits simultaneously in opposite directions using a single pair of maximally entangled qudits is presented. This procedure works provided that the product of dimensions d_1 and d_2 of the two qudits to be teleported does not exceed the dimension d of the individual qudits in the maximally entangled pair.
Entangled states are essential in basics quantum communication protocols and quantum cryptography. Ferromagnetic contacts can work as a spin detector, giving possibility of converting information about electron spin to the electric charge, and therefore, detection of entangled states with the electric current measurements is possible. Method of confirming entanglement with non-ideal detectors is presented, the impact of decoherence and noise on states and quality of entanglement is discussed. Entanglement witness (EW) operator method is compared with the CHSH inequalities approach. Required spin polarization for the EW is lower than for the CHSH inequalities. System with asymmetric spin polarizations of detectors was analyzed, including the CHSH inequalities and the EW method.
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.