Observation of Bloch oscillations in complex PT-symmetric photonic lattices
Open Access
- 7 December 2015
- journal article
- research article
- Published by Springer Nature in Scientific Reports
- Vol. 5 (1), 17760
- https://doi.org/10.1038/srep17760
Abstract
Light propagation in periodic environments is often associated with a number of interesting and potentially useful processes. If a crystalline optical potential is also linearly ramped, light can undergo periodic Bloch oscillations, a direct outcome of localized Wannier-Stark states and their equidistant eigenvalue spectrum. Even though these effects have been extensively explored in conservative settings, this is by no means the case in non-Hermitian photonic lattices encompassing both amplification and attenuation. Quite recently, Bloch oscillations have been predicted in parity-time-symmetric structures involving gain and loss in a balanced fashion. While in a complex bulk medium, one intuitively expects that light will typically follow the path of highest amplification, in a periodic system this behavior can be substantially altered by the underlying band structure. Here, we report the first experimental observation of Bloch oscillations in parity-time-symmetric mesh lattices. We show that these revivals exhibit unusual properties like secondary emissions and resonant restoration of PT symmetry. In addition, we present a versatile method for reconstructing the real and imaginary components of the band structure by directly monitoring the light evolution during a cycle of these oscillations.This publication has 24 references indexed in Scilit:
- Experimental demonstration of a unidirectional reflectionless parity-time metamaterial at optical frequenciesNature Materials, 2012
- Observation of parity–time symmetry in opticsNature Physics, 2010
- Visualization of Branch Points in-Symmetric WaveguidesPhysical Review Letters, 2008
- Beam Dynamics inSymmetric Optical LatticesPhysical Review Letters, 2008
- Experimental Observation of Linear and Nonlinear Optical Bloch OscillationsPhysical Review Letters, 1999
- Real Spectra in Non-Hermitian Hamiltonians HavingSymmetryPhysical Review Letters, 1998
- Bloch Oscillations of Atoms in an Optical PotentialPhysical Review Letters, 1996
- Coherent submillimeter-wave emission from Bloch oscillations in a semiconductor superlatticePhysical Review Letters, 1993
- A theory of the electrical breakdown of solid dielectricsProceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 1934
- ber die Quantenmechanik der Elektronen in KristallgitternThe European Physical Journal A, 1929