相关论文: Absence of quantum optical coherence in high harmo…
Using numerical simulations, we show that atomic high order harmonic generation, HHG, with a circularly polarized laser field offers an ideal framework for quantum-classical correspondence in strong field physics. With an appropriate…
The relations between quantum coherence and quantum interference are discussed. A general method for generation of quantum coherence through interference-induced state selection is introduced and then applied to `simple' atomic systems…
Quantum entanglement generation is generally known to be impossible by any classical means. According to Poisson statistics, coherent photons are not considered quantum particles due to the bunching phenomenon. Recently, a coherence…
A three step model for high harmonic generation from impurities in solids is developed. The process is found to be similar to high harmonic generation in atomic and molecular gases with the main difference coming from the non-parabolic…
We propose and experimentally demonstrate a scheme allowing to reach noncollinear phase-matching of high harmonic generation in solids, which may potentially lead to an enhancement of the generation efficiency. The principle is based on…
The interaction of electrons with strong laser fields is usually treated with semiclassical theory, where the laser is represented by an external field. There are analytic solutions for the free electron wave functions, which incorporate…
We consider a quantum harmonic oscillator coupled with a graviton bath and discuss the loss of coherence in the matter sector due to the matter-graviton vertex interaction. Working in the quantum-field-theory framework, we obtain a master…
Coherent quantum optics, where the interaction of a photon with an emitter does not scramble phase coherence, lies at the heart of many quantum optical effects and emerging technologies. Solid-state emitters coupled to nanophotonic…
The solid-state harmonic generation (SSHG) derives from photocurrent coherence. The crystal symmetry, including point-group symmetry and time-reversal symmetry, constrains the amplitude and phase of the photocurrent, thus manipulates the…
We investigate a two-level atom in the field of a strong laser pulse. The resulting time-dependent polarization is the source of a radiation the frequency components of which are essentially harmonics of the driving field's carrier…
The generation of photocurrents due to coupling of electrons to both classical and quantized electromagnetic fields in thin semiconductor films is described within the framework of the nonequilibrium Green's function formalism. For the…
We develop and exactly solve a model for electrons driven by pulsed or continuous ac fields. The theory includes both the photoexcitation process as well as the subsequent acceleration of the electrons. In the case of an ac response, we…
Harmonic generation in atoms and molecules has reshaped our understanding of ultrafast phenomena beyond the traditional nonlinear optics and has launched attosecond physics. Harmonics from solids represent a new frontier, where both…
Symmetries essentially provide conservation rules in nonlinear light-matter interactions, that facilitate control and understanding of photon conversion processes or electron dynamics. Since anisotropic solids have rich symmetries, they are…
High-order harmonic generation (HHG) by hydrogenlike atoms/ions in the uniform periodic electric field, formed by the two linearly polarized counterpropagating laser beams of relativistic intensities, is studied. The relativistic quantum…
High-harmonic generation (HHG) of a two-level-system driven by an intense monochromatic phase-locked laser is studied in terms of complex spectral analysis with the Floquet method. In contrast to the phenomenological approaches, this…
On-chip quantum sources based on nonlinear processes are pivotal components in integrated photonics, driving significant advancements in quantum information technologies over recent decades. Usually, the pump coherence has been considered…
High order harmonic (HOH) generation by interacting extremely intense electromagnetic waves in the quantum vacuum is investigated within the framework of the Heisenberg-Euler formalism. We consider here the process in the lowest order of a…
Coherent generation of indistinguishable single photons is crucial for many quantum communication and processing protocols. Solid-state realizations of two-level atomic transitions or three-level spin-$\Lambda$ systems offer significant…
The control of light-matter interaction at the quantum level usually requires coherent laser fields. But already an exchange of virtual photons with the electromagnetic vacuum field alone can lead to quantum coherences, which subsequently…