By exploiting recent developments associated with parity-time (PT) symmetry in optics, we here propose a new avenue in realizing single-mode large area laser amplifiers. This can be accomplished by utilizing the abrupt symmetry breaking transition that allows the fundamental mode to experience gain while keeping all the higher order modes neutral. Such PT-symmetric structures can be realized by...

For an invertible (bounded) linear operator Q acting in a Hilbert space H, we consider the consequences of the QT -symmetry of a non-Hermitian Hamiltonian H : H → H where T is the time-reversal operator. If H is symmetric in the sense that THT = H, then QT symmetry is equivalent toQ-weak-pseudo-Hermiticity. But in general this equivalence does not hold. We show this using some specific examples...

We study certain linear and antilinear symmetry generators and involution operators associated with pseudo-Hermitian Hamiltonians and show that the theory of pseudoHermitian operators provides a simple explanation for the recent results of Bender, Brody and Jones (quant-ph/0208076) on the CPT -symmetry of a class of PT -symmetric nonHermitian Hamiltonians. We present a natural extension of thes...

Abstract The dynamics of an open quantum system with balanced gain and loss is not described by a PT-symmetric Hamiltonian but rather Lindblad operators. Nevertheless the phenomenon PT-symmetry breaking impact exceptional points can be observed in Lindbladean dynamics. Here we briefly review development PT symmetry mechanics, characterisation systems terms behaviour speed evolution state.

The complex generalization of conventional quantum mechanics has been investigated extensively in recent years. In particular it is shown that the standard formulation of quantum mechanics in terms of Hermitian Hamiltonians is overly restrictive and a consistent physical theory of quantum mechanics can be built on a complex Hamiltonian that is not Hermitian but satisfies the less restrictive an...

We show that the evolution of the wave functions in the PT symmetric quantum mechanics is pseudo-unitary. Their pseudo-norm 〈ψ|P|ψ〉 remains time-independent. This persists even if the PT symmetry itself becomes spontaneously broken. PACS 03.65.Bz, 03.65.Ca 03.65.Fd February 3, 2008, spon.tex file

We study scattering properties of a PT -symmetric square well potential with real depth larger than the threshold of particle-antiparticle pair production as the time component of a vector potential in the Dirac equation. Spontaneous pair production inside the well becomes tiny beyond the strength at which discrete bound states with real energies disappear, consistently with a spontaneous break...

Closed expressions are derived for the pseudo-norm, norm and orthogonality relations for arbitrary bound states of the PT symmetric and the Hermitian Scarf II potential for the first time. The pseudo-norm is found to have indefinite sign in general. Some aspects of the spontaneous breakdown of PT symmetry are analysed.

The asymmetric unit of the title compound, (C(24)H(20)P)(2)[Pt(C(7)H(5)NO(2)S(3))(2)]·H(2)O, consists of two tetra-phenyl-phospho-nium cations, two half bis-[N-(phenyl-sulfon-yl)dithio-carbim-ato]platinate(II) dianions and one water mol-ecule. The anions are completed by crystallographic inversion symmetry associated with the central Pt(II) ion. The Pt(II) ion is doubly S,S'-chelated by two sym...

led Bender and Boettcher to conjecture that under suitable boundary conditions the spectrum of (1) was entirely real and positive provided M ≥ 1 [2]. Bender and Boettcher also noticed the relevance of PT -symmetry [2,3] to these problems. For all M , the potentials V (x) = −(ix)2M are invariant under the combined action of parity and time reversal, and this implies the eigenvalues are either re...