Filters

2018 - 201912020 - 20212

More filters

20233
Reset filters

Settings

search.filters.applied.f.access: openAccess × Author: Ivanov, Misha × Start date: 2023 × DDC: 500 × Publisher: [London] : Nature Publishing Group UK ×

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Enantio-sensitive unidirectional light bending
    ([London] : Nature Publishing Group UK, 2021) Ayuso, David; Ordonez, Andres F.; Decleva, Piero; Ivanov, Misha; Smirnova, Olga
    Structured light, which exhibits nontrivial intensity, phase, and polarization patterns in space, has key applications ranging from imaging and 3D micromanipulation to classical and quantum communication. However, to date, its application to molecular chirality has been limited by the weakness of magnetic interactions. Here we structure light’s local handedness in space to introduce and realize an enantio-sensitive interferometer for efficient chiral recognition without magnetic interactions, which can be seen as an enantio-sensitive version of Young’s double slit experiment. Upon interaction with isotropic chiral media, such chirality-structured light effectively creates chiral emitters of opposite handedness, located at different positions in space. We show that if the distribution of light’s handedness breaks left-right symmetry, the interference of these chiral emitters leads to unidirectional bending of the emitted light, in opposite directions in media of opposite handedness, even if the number of the left-handed and right-handed emitters excited in the medium is exactly the same. Our work introduces the concepts of polarization of chirality and chirality-polarized light, exposes the immense potential of sculpting light’s local chirality, and offers novel opportunities for efficient chiral discrimination, enantio-sensitive optical molecular fingerprinting and imaging on ultrafast time scales.
  • Thumbnail Image
    Item
    Topological protection versus degree of entanglement of two-photon light in photonic topological insulators
    ([London] : Nature Publishing Group UK, 2021) Tschernig, Konrad; Jimenez-Galán, Álvaro; Christodoulides, Demetrios N.; Ivanov, Misha; Busch, Kurt; Bandres, Miguel A.; Perez-Leija, Armando
    Topological insulators combine insulating properties in the bulk with scattering-free transport along edges, supporting dissipationless unidirectional energy and information flow even in the presence of defects and disorder. The feasibility of engineering quantum Hamiltonians with photonic tools, combined with the availability of entangled photons, raises the intriguing possibility of employing topologically protected entangled states in optical quantum computing and information processing. However, while two-photon states built as a product of two topologically protected single-photon states inherit full protection from their single-photon “parents”, a high degree of non-separability may lead to rapid deterioration of the two-photon states after propagation through disorder. In this work, we identify physical mechanisms which contribute to the vulnerability of entangled states in topological photonic lattices. Further, we show that in order to maximize entanglement without sacrificing topological protection, the joint spectral correlation map of two-photon states must fit inside a well-defined topological window of protection.
  • Thumbnail Image
    Item
    Attosecond recorder of the polarization state of light
    ([London] : Nature Publishing Group UK, 2018) Jiménez-Galán, Álvaro; Dixit, Gopal; Patchkovskii, Serguei; Smirnova, Olga; Morales, Felipe; Ivanov, Misha
    High harmonic generation in multi-color laser fields opens the opportunity of generating isolated attosecond pulses with high ellipticity. Such pulses hold the potential for time-resolving chiral electronic, magnetization, and spin dynamics at their natural timescale. However, this potential cannot be realized without characterizing the exact polarization state of light on the attosecond timescale. Here we propose and numerically demonstrate a complete solution of this problem. Our solution exploits the extrinsic two-dimensional chirality induced in an atom interacting with the chiral attosecond pulse and a linearly polarized infrared probe. The resulting asymmetry in the photoelectron spectra allows to reconstruct the complete polarization state of the attosecond pulse, including its possible time dependence. The challenging problem of distinguishing circularly polarized, partially polarized, or unpolarized pulses in the extreme ultraviolet range is also resolved. We expect this approach to become the core ingredient for attosecond measurements of chiral-sensitive processes in gas and condensed phase.