Tunneling of optical pulses at 1.5 µm wavelength through double-barrier periodic fiber Bragg grat... more Tunneling of optical pulses at 1.5 µm wavelength through double-barrier periodic fiber Bragg gratings is experimentally investigated. Tunneling time measurements as a function of barrier distance show that, far from the res- onances of the structure, the transit time is paradoxically short, implying Superluminal propagation, and almost independent of the distance between the barriers. These results are in agreement with
Conference Digest. 2000 Conference on Lasers and Electro-Optics Europe (Cat. No.00TH8505), 2000
Summary form only given. Techniques for multiplication of pulse trains repetition rate are of maj... more Summary form only given. Techniques for multiplication of pulse trains repetition rate are of major importance for the development of future ultrahigh-speed optical transmission systems in the 15 μm wavelength region. A promising and simple method is based on the linear propagation of the pulse train in a highly dispersive medium exploiting, in the time domain by multiple pulse interference, a condition analogous to that found in the fractional Talbot effect of diffractive optics. Here we report on the first experimental demonstration of pulse train multiplication based on the temporal Talbot effect, using a suitably designed linearly-chirped fiber grating as a dispersive element
2005 Quantum Electronics and Laser Science Conference, 2005
Existence of dispersion-free and diffraction-free ultra-short vectorial pulsed Bessel beams is pr... more Existence of dispersion-free and diffraction-free ultra-short vectorial pulsed Bessel beams is predicted in one-dimensional photonic bandgaps (PBGs) using a Wannier-function technique. Pulsed Bessel beam propagation in a GaAs layered PBG is in particular considered.
Postconference Digest Quantum Electronics and Laser Science, 2003. QELS., 2003
The properties of beam propagation in a periodically-curved optical waveguide beyond the usual pe... more The properties of beam propagation in a periodically-curved optical waveguide beyond the usual perturbative approach are theoretically studied. The existence of unusual and exotic effects, such as dynamic beam splitting, dynamic directional coupling, and reduction of radiation losses are also shown. These unusual and exotic effects are fully similar to the phenomena of dynamic wave function stabilization, ionization quenching and
CLEO/Europe. 2005 Conference on Lasers and Electro-Optics Europe, 2005., 2005
In this contribution, we present a novel class of vectorial pulsed Bessel beams that can propagat... more In this contribution, we present a novel class of vectorial pulsed Bessel beams that can propagate in a one-dimensional photonic band gap (PBG) free of diffraction and pulse broadening. Non-diffractive and non-dispersive pulsed Bessel beams solutions require the second order group velocity dispersion to be zero, a condition which is always satisfied at frequencies where the band structure has a
ABSTRACT We theoretically demonstrate that a type of robust two-particle bound state embedded in ... more ABSTRACT We theoretically demonstrate that a type of robust two-particle bound state embedded in the continuum (BIC), which we call Floquet-Hubbard (FH) BIC, can be induced in a homogeneous (i.e., defect-free) Hubbard semilattice by an intense oscillating electric field. While single-particle BIC states are fragile states that exist solely for specially tailored potentials, FH BIC states are found in a wide range of parameter space, do not require fulfillment of resonance conditions, and are thresholdless. Analytical results are derived in the high-frequency limit of field modulation by a multiple-time-scale asymptotic analysis of the ac-driven Hubbard Hamiltonian in the two-particle sector. A FH BIC mode basically corresponds to a molecular state, in which the two particles bind together, undergoing correlated tunneling on the lattice. Localization of the molecular state is induced by the external oscillating field, which effectively attracts the molecular state at the edge of the semi-infinite lattice. Our results can pave the way for the study and interpretation of strong-field phenomena in correlated-particles physics.
ABSTRACT A classical analog simulator of the two-site Hubbard-Holstein model, describing the dyna... more ABSTRACT A classical analog simulator of the two-site Hubbard-Holstein model, describing the dynamics of two correlated electrons coupled with local phonons, is proposed based on light transport in engineered optical waveguide arrays. Our photonic analog simulator enables to map the temporal dynamics of the quantum system in Fock space into spatial propagation of classical light waves in the evanescently-coupled waveguides of the array. In particular, in the strong correlation regime the periodic temporal dynamics, related to the excitation of Holstein polarons with equal energy spacing, can be visualized as a periodic self-imaging phenomenon of the light beam along the waveguide array and explained in terms of generalized Bloch oscillations of a single particle in a semi-infinite inhomogeneous tight-binding lattice.
ABSTRACT A non-Hermitian shortcut to adiabaticity is introduced. By adding an imaginary term in t... more ABSTRACT A non-Hermitian shortcut to adiabaticity is introduced. By adding an imaginary term in the diagonal elements of the Hamiltonian of a two state quantum system, we show how one can cancel the nonadiabatic losses and perform an arbitrarily fast population transfer, without the need to increase the coupling. We apply this technique to two popular level-crossing models: the Landau-Zener model and the Allen-Eberly model.
ABSTRACT It is theoretically shown that the coherent hopping dynamics of a non-relativistic parti... more ABSTRACT It is theoretically shown that the coherent hopping dynamics of a non-relativistic particle in engineered tight-binding lattices subjected to combined ac and dc driving forces can mimic in Fock space relativistic quantum field theories (QFTs) of strongly interacting fields, enabling access to extreme dynamical regimes beyond weak coupling and perturbative predictions. In particular, the simulation of a QFT model describing a Dirac field strongly coupled to a scalar bosonic field via a Yukawa coupling is proposed, suggesting the possibility of implementing this model using engineered lattices of evanescently coupled optical waveguides with a bent optical axis.
Commercial and Biomedical Applications of Ultrafast Lasers IX, 2009
... 13 Send correspondence to E-mail: heinrich@iap.uni-jena.de Commercial and Biomedical Applicat... more ... 13 Send correspondence to E-mail: heinrich@iap.uni-jena.de Commercial and Biomedical Applications of Ultrafast Lasers IX, edited by Joseph Neev, Stefan Nolte, Alexander Heisterkamp, Rick P. Trebino, Proc. ... 7203 72030K-5 Page 6. [5] Wu, C., Somervell, A., Haskell, T., and ...
Tunneling of optical pulses at 1.5 µm wavelength through double-barrier periodic fiber Bragg grat... more Tunneling of optical pulses at 1.5 µm wavelength through double-barrier periodic fiber Bragg gratings is experimentally investigated. Tunneling time measurements as a function of barrier distance show that, far from the res- onances of the structure, the transit time is paradoxically short, implying Superluminal propagation, and almost independent of the distance between the barriers. These results are in agreement with
Conference Digest. 2000 Conference on Lasers and Electro-Optics Europe (Cat. No.00TH8505), 2000
Summary form only given. Techniques for multiplication of pulse trains repetition rate are of maj... more Summary form only given. Techniques for multiplication of pulse trains repetition rate are of major importance for the development of future ultrahigh-speed optical transmission systems in the 15 μm wavelength region. A promising and simple method is based on the linear propagation of the pulse train in a highly dispersive medium exploiting, in the time domain by multiple pulse interference, a condition analogous to that found in the fractional Talbot effect of diffractive optics. Here we report on the first experimental demonstration of pulse train multiplication based on the temporal Talbot effect, using a suitably designed linearly-chirped fiber grating as a dispersive element
2005 Quantum Electronics and Laser Science Conference, 2005
Existence of dispersion-free and diffraction-free ultra-short vectorial pulsed Bessel beams is pr... more Existence of dispersion-free and diffraction-free ultra-short vectorial pulsed Bessel beams is predicted in one-dimensional photonic bandgaps (PBGs) using a Wannier-function technique. Pulsed Bessel beam propagation in a GaAs layered PBG is in particular considered.
Postconference Digest Quantum Electronics and Laser Science, 2003. QELS., 2003
The properties of beam propagation in a periodically-curved optical waveguide beyond the usual pe... more The properties of beam propagation in a periodically-curved optical waveguide beyond the usual perturbative approach are theoretically studied. The existence of unusual and exotic effects, such as dynamic beam splitting, dynamic directional coupling, and reduction of radiation losses are also shown. These unusual and exotic effects are fully similar to the phenomena of dynamic wave function stabilization, ionization quenching and
CLEO/Europe. 2005 Conference on Lasers and Electro-Optics Europe, 2005., 2005
In this contribution, we present a novel class of vectorial pulsed Bessel beams that can propagat... more In this contribution, we present a novel class of vectorial pulsed Bessel beams that can propagate in a one-dimensional photonic band gap (PBG) free of diffraction and pulse broadening. Non-diffractive and non-dispersive pulsed Bessel beams solutions require the second order group velocity dispersion to be zero, a condition which is always satisfied at frequencies where the band structure has a
ABSTRACT We theoretically demonstrate that a type of robust two-particle bound state embedded in ... more ABSTRACT We theoretically demonstrate that a type of robust two-particle bound state embedded in the continuum (BIC), which we call Floquet-Hubbard (FH) BIC, can be induced in a homogeneous (i.e., defect-free) Hubbard semilattice by an intense oscillating electric field. While single-particle BIC states are fragile states that exist solely for specially tailored potentials, FH BIC states are found in a wide range of parameter space, do not require fulfillment of resonance conditions, and are thresholdless. Analytical results are derived in the high-frequency limit of field modulation by a multiple-time-scale asymptotic analysis of the ac-driven Hubbard Hamiltonian in the two-particle sector. A FH BIC mode basically corresponds to a molecular state, in which the two particles bind together, undergoing correlated tunneling on the lattice. Localization of the molecular state is induced by the external oscillating field, which effectively attracts the molecular state at the edge of the semi-infinite lattice. Our results can pave the way for the study and interpretation of strong-field phenomena in correlated-particles physics.
ABSTRACT A classical analog simulator of the two-site Hubbard-Holstein model, describing the dyna... more ABSTRACT A classical analog simulator of the two-site Hubbard-Holstein model, describing the dynamics of two correlated electrons coupled with local phonons, is proposed based on light transport in engineered optical waveguide arrays. Our photonic analog simulator enables to map the temporal dynamics of the quantum system in Fock space into spatial propagation of classical light waves in the evanescently-coupled waveguides of the array. In particular, in the strong correlation regime the periodic temporal dynamics, related to the excitation of Holstein polarons with equal energy spacing, can be visualized as a periodic self-imaging phenomenon of the light beam along the waveguide array and explained in terms of generalized Bloch oscillations of a single particle in a semi-infinite inhomogeneous tight-binding lattice.
ABSTRACT A non-Hermitian shortcut to adiabaticity is introduced. By adding an imaginary term in t... more ABSTRACT A non-Hermitian shortcut to adiabaticity is introduced. By adding an imaginary term in the diagonal elements of the Hamiltonian of a two state quantum system, we show how one can cancel the nonadiabatic losses and perform an arbitrarily fast population transfer, without the need to increase the coupling. We apply this technique to two popular level-crossing models: the Landau-Zener model and the Allen-Eberly model.
ABSTRACT It is theoretically shown that the coherent hopping dynamics of a non-relativistic parti... more ABSTRACT It is theoretically shown that the coherent hopping dynamics of a non-relativistic particle in engineered tight-binding lattices subjected to combined ac and dc driving forces can mimic in Fock space relativistic quantum field theories (QFTs) of strongly interacting fields, enabling access to extreme dynamical regimes beyond weak coupling and perturbative predictions. In particular, the simulation of a QFT model describing a Dirac field strongly coupled to a scalar bosonic field via a Yukawa coupling is proposed, suggesting the possibility of implementing this model using engineered lattices of evanescently coupled optical waveguides with a bent optical axis.
Commercial and Biomedical Applications of Ultrafast Lasers IX, 2009
... 13 Send correspondence to E-mail: heinrich@iap.uni-jena.de Commercial and Biomedical Applicat... more ... 13 Send correspondence to E-mail: heinrich@iap.uni-jena.de Commercial and Biomedical Applications of Ultrafast Lasers IX, edited by Joseph Neev, Stefan Nolte, Alexander Heisterkamp, Rick P. Trebino, Proc. ... 7203 72030K-5 Page 6. [5] Wu, C., Somervell, A., Haskell, T., and ...
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