Experimentelle und theoretische Untersuchung von räumlich lokalisierten Anregungen in nichtlinearen Gittern

• Applicant: Professor Dr. Sergej Flach
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2000 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5229370

• Final Report Year: 2008

Final Report Abstract

We studied the resonant scattering of plasmons (linear waves) by discrete breather excitations in Josephson junction ladders. We predicted the existence of Fano resonances, and found them by computing the resonant vanishing of the transmission coefficient. We performed a thorough theoretical analysis of two interacting quantum Josephson junctions. We performed a systematic analysis of the tunneling frequency, site correlations, fluctuations of the number of quanta, and entanglement of quantum breather states. They showed strong site correlation of quanta and are characterized by a strong excitation of quanta on one junction which perform slow coherent tunneling motion from one junction to the other. They suppress fluctuations of the total number of excited quanta.

Publications

• Spin filters with Fano dots. Eur. Phys. J, B 37 (2004) 399
  M. E. Torio, K. Hallberg, S, Flach, A. E. Miroshnichenko and M. Titov
  
• Nonlinear Fano resonance and bistable wave transmission. Phys. Rev. E 71, 036626 (2005)
  A. E. Miroshnichenko, S. F. Mingaleev, S. Flach and Yu. S. Kivshar
  
• Resonant light scattering by optical solitons. Phys. Rev. Lett. 95 (2005) 023901
  S. Flach, V. Fleurov and A. Gorbach and A. E. Miroshnichenko
  
• Resonant plasmon scattering by discrete breathers in Josephson junction ladders. Phys, Rev. B 71, 174306 (2005)
  A. E. Miroshnichenko, M. Schuster, S. Flach, M. V. Fistul and A. V. Ustinov
  
• Quantum dynamics of localized excitations in a symmetric trimer molecule. Phys. Rev. A 73 (2006) 022717
  R. A. Pinto and S. Flach
  
• Quantum localized modes in capacitively coupled Josephson junctions. Europliys. Lett. 79, 66002 (2007)
  R. Pinto and Sergej Flach
  
• Quantum q-breathers in a finite Bosc-Hubbard chain: the case of two interacting bosons. Phys. Rev. B 75, 214303 (2007)
  J. P. Nguenang, R. A. Pinto and S. Flach
  
• Quantum breathers in capacitively coupled Josephson junctions: Correlations, number conservation, and entanglement. Phys. Rev. B 77, 024308 (2008)
  R. Pinto and Sergej Flach