Noncritical quadrature squeezing through spontaneous polarization symmetry breaking

Noncritical quadrature squeezing through spontaneous polarization symmetry breaking.

We discuss the possibility of generating noncritical quadrature squeezing by spontaneous polarization symmetry breaking. We first consider Type II frequency-degenerate optical parametric oscillators but discard them for a number of reasons. Then we propose a four-wave-mixing cavity, in which the polarization of the output mode is always linear but has an arbitrary orientation. We show that in s...

Spontaneous Symmetry Breaking through Mixing

We discuss a model, in which the negative mass square needed in the Higgs mechanism is generated by mixing with a heavy scalar. We have two scalar doublets in the standard model. Phenomenological properties of the heavy new scalar are discussed. The heavy scalar can be detected by the LHC. In the Standard Model (SM) the masses of the Wand Z-bosons and of the fermions (leptons and quarks) are in...

Nonperturbative Spontaneous Symmetry Breaking

One of the most astonishing results of quantum field theory is spontaneous symmetry breaking. One can say that it is the situation when something arises from the quantization. This means that on the quantum level one has something that was not present on the classical level. Coleman and Weinberg [1] write : “ . . . higher-order effects may qualitatively change the character of a physical theory...

Spontaneous Symmetry Breaking

Decoherence induced spontaneous symmetry breaking

We study time dependence of exchange symmetry properties of Bell states when two-qubits interact with local baths having identical parameters. In case of classical noise, we consider a decoherence Hamiltonian which is invariant under swapping the first and second qubits. We find that as the system evolves in time, two of the three symmetric Bell states preserve their qubit exchange symmetry wit...