arXiv subjects
Publications and source records attributed to Juan Carlos Garcia-Escartin.
We show that universal quantum logic can be achieved using only linear optics and a quantum shutter device. With these elements, we design a quantum memory for any number of qubits and a CNOT gate which are the basis of a universal quantum computer. An interaction-free model for a quantum shutter is given.
Interaction-free measurement and quantum interrogation schemes can help in the detection of particles without interacting with them in a classical sense. We present a density matrix study of a quantum interrogation system designed for particles that need not to be perfectly absorptive and compare the results to those of the usual setup.
We give a proposal for the physical implementation of a quantum shutter. This shutter is a mechanism able to close the passage of light through a slit when present. As it must be a quantum mechanical object, able to show superposition, interesting quantum effects are observed. Finally, we review some applications of the quantum shutter to build quantum memories and a CNOT gate.
In the same way that classical computer networks connect and enhance the capabilities of classical computers, quantum networks can combine the advantages of quantum information and communications. We propose a non-classical network element, a delayed commutation switch, that can solve the problem of switching time in packet switching networks. With the help of some local ancillary qubits and superdense codes we can route the information after part of it has left the network node.