Parity-time (PT) symmetric periodic structures, near the spontaneous PT-symmetry breaking point, can act as unidirectional invisible media. In this regime, the reflection from one end is diminished while it is enhanced from the other. Furthermore, the transmission coefficient and phase are indistinguishable from those expected in the absence of a grating. The phenomenon is robust even in the pr...

We study the propagation of linear waves and solitons in an array of optical waveguides with an embedded defect created by a pair of waveguides with gain and loss satisfying the socalled parity-time (PT ) symmetry condition. We demonstrate that in the case of small soliton amplitudes, the linear theory describes the scattering of solitons with a good accuracy. We find that the incident high-amp...

In the crystal structure of the title complex, [Pt(C(5)H(4)NOS)(2)], the Pt atom is coordinated by two O atoms and two S atoms in a cis configuration, forming a distorted square-planar coordination geometry. The mol-ecule exhibits pseudo-C(2v) symmetry and is essentially planar, with a maximum deviation from planarity of 0.0124 (2) Å. The dihedral angle between the two pyridine rings is 5.85 (2)°.

Two-dimensional PT-symmetric quantum-mechanical systems with the complex cubic potential V 12 = x 2 + y 2 + igxy 2 and the complex Hénon-Heiles potential V HH = x 2 + y 2 + ig xy 2 − x 3 /3 are investigated. Using numerical and perturbative methods, energy spectra are obtained to high levels. Although both potentials respect the PT symmetry, the complex energy eigenvalues appear when level cros...

The observation that PT-symmetric Hamiltonians can have real-valued energy levels even if they are non-Hermitian has triggered intense activities, with experiments, in particular, focusing on optical systems, where Hermiticity can be broken by absorption and amplification. For classical waves, absorption and amplification are related by time-reversal symmetry. This work shows that microreversib...

An exactly solvable discrete PT invariant nonlinear Schrödinger-like model is introduced. It is an integrable Hamiltonian system that exhibits a nontrivial nonlinear PT symmetry. A discrete one-soliton solution is constructed using a left-right Riemann-Hilbert formulation. It is shown that this pure soliton exhibits unique features such as power oscillations and singularity formation. The propo...

We propose a one-way invisible cloak using transformation optics of parity-time (PT) symmetric optical materials. At the spontaneous PT-symmetry breaking point, light is scattered only for incidence along one direction since the phase-matching condition is unidirectionally satisfied, making the cloak one-way invisible. Moreover, optical scattering from the one-way cloak can be further engineere...

The one-dimensional Coulomb-like potential with a real coupling constant β, and a centrifugal-like core of strength G = α − 1 4 , viz., V (x) = α− 1 4 (x−ic) + β |x−ic| , is discussed in the framework of PT -symmetry. The PT -invariant exactly solvable model so formed, is found to admit a double set of real and discrete energies, numbered by a quasi-parity q = ±1. ———————————————————– ————————————

In the title salt, (C(24)H(20)P)(2)[Pt(C(7)H(3)Cl(2)NO(2)S(3))(2)], the Pt(II) ion (site symmetry ) is coordinated by two S,S'-bidentate N-(2,5-dichloro-phenyl-sulfon-yl)dithio-carbimate ligands, resulting in a slightly distorted PtS(4) square-planar geometry. In the crystal, a C-H⋯O inter-action is observed, as well as electrostatic attraction between the oppositely charged ions.

PT-symmetric Hamiltonians and transfer matrices arise naturally in statistical mechanics. These classical and quantum models often require the use of complex or negative weights and thus fall outside the conventional equilibrium statistical mechanics of Hermitian systems. PT-symmetric models form a natural class where the partition function is necessarily real, but not necessarily positive. The...