20 research outputs found
Quantum teleportation with nonclassical correlated states in noninertial frames
Quantum teleportation is studied in noninertial frame, for fermionic case,
when Alice and Bob share a general nonclassical correlated state. In
noninertial frames two fidelities of teleportation are given. It is found that
the average fidelity of teleportation from a separable and nonclassical
correlated state is increasing with the amount of nonclassical correlation of
the state. However, for any particular nonclassical correlated state, the
fidelity of teleportation decreases by increasing the acceleration.Comment: 10 pages, 3 figures, expanded version to appear in Quantum Inf.
Proces
An exactly solvable quantum-lattice model with a tunable degree of nonlocality
An array of N subsequent Laguerre polynomials is interpreted as an
eigenvector of a non-Hermitian tridiagonal Hamiltonian with real spectrum
or, better said, of an exactly solvable N-site-lattice cryptohermitian
Hamiltonian whose spectrum is known as equal to the set of zeros of the N-th
Laguerre polynomial. The two key problems (viz., the one of the ambiguity and
the one of the closed-form construction of all of the eligible inner products
which make Hermitian in the respective {\em ad hoc} Hilbert spaces) are
discussed. Then, for illustration, the first four simplest, parametric
definitions of inner products with and are explicitly
displayed. In mathematical terms these alternative inner products may be
perceived as alternative Hermitian conjugations of the initial N-plet of
Laguerre polynomials. In physical terms the parameter may be interpreted as
a measure of the "smearing of the lattice coordinates" in the model.Comment: 35 p
Non-Hermitian Hamiltonians with a Real Spectrum and Their Physical Applications
We present an evaluation of some recent attempts at understanding the role of
pseudo-Hermitian and PT-symmetric Hamiltonians in modeling unitary quantum
systems and elaborate on a particular physical phenomenon whose discovery
originated in the study of complex scattering potentials.Comment: 9 pages, contributed to Homi Bhabha Centenary Conference on
Non-Hermitian Hamiltonians in Quantum Physics (8th International Workshop on
Pseudo-Hermitian Hamiltonians in Quantum Physics), held in Mumbai, January
13-16, 200