Discrete & Quantum Breathers in Metmaterials

Discrete Breathers:

In the field of Nonlinear Optical Materials, e.g. Metamaterials, for important applications of Discrete Breathers (DBs) or Intrinsic Localized Mode (ILM) (Sievers et al, PRL, 1988; Bandyopadhyay et al, PRB, 2010 and 2011) some systems are mentioned here: a) Solid State Mixed-Valence Transition Metal Complexes, b) Quasi-1D Antiferromagnetic Chains, c) Array of Josephson Junctions, d) Oscillators in  Micromechanical System, e) Optical Waveguide Systems, and also important molecules for biotechnology, such as f) Proteins.

DBs modify system properties viz. lattice thermodynamics and introduce the possibility of non-dispersive energy transport, because of their potential application for translatory motion along the lattice. These DBs are observed both in integrable and non-integrable systems.

Fano resonance due to DBs have also been studied by Flach et al (PRL, 2003) and were also explored in terms of some material parameters by Bandyopadhyay et al (JOSA-B, 2012). This type of study was important for various applications, e.g. in the (a) biosensing technology, (b) spectral selectivity, (c) beam filtering, etc.

Quantum Breathers:

           After DBs, next let us go to the applications of Quantum Breathers (QB) due to a possible interest in the field of Quantum Computation. To name a few: Reconfigurable Metamaterials (Quach et al, Optical Express, 2011) and Quantum Archimedean Screw for Superconducting Electronics using Metamaterials (Rakhmanov et al, PRB, 2008), and many others from Medicine to Aeorospace applications. There are so many other applications: a) Ladder Array of Josephson Junction for Superconductors, b) BEC in Optical Lattices or Nonlinear Photonic Lattices, c) Interacting Optical Waveguides, d) Cantilever Vibrations in Micro-mechanical Arrays, e) Macromolecules, such as DNA, f) Quantum Metamaterials based Superconductors, g) Modulation Instability-based Gadgets, g) Split-Ring-Resonator (SRR) based Metamaterials in Antenna Arrays, i.e. THz applications by minimizing losses (To Note: the ‘coherent quantum dynamics’ of ‘qubits’ determines the THz optical properties in the system) h) Two-Magnon Bound States (TMBS) in Antiferromagnets and  i) Two-Phonon Bound States (TPBS), i.e. Quantum Breathers as investigated by Fourier Grid Hamiltonian method. QBs can be generally described by both periodic (JAP, 2011a) and non-periodic boundary conditions (JAP, 2011b) respectively. The quantum-effect enabled systems via Metamaterials route will bring a range of exciting applications in the future (Zheludev, Opt. & Photon News, 2011).

Finally, another interesting application is mentioned here on the rectification of current density, i.e. Ratchet Solitons, (Flach et al, PRL, 2002;  Bandyopadhyay et al, JPD, 2013) through the analysis of symmetry and its violation in Metamaterials. The relevant applications are: (a) Molecular Motors and other Non-equilibrium Biological Systems, (b) Electric Currents in Superlattices, (c) Voltages in Coupled Systems, i.e. in annular Josephson Junctions revealing unidirectional Fluxon Motion that is driven by Biharmonic Microwaves, (d) Magnetic Flux Cleaning in Superconducting Films, (e) Abrikosov Vortex Diodes, and (f) Voltage Rectifiers.