We considered one-dimensional chain of the two-level quantum systems coupled via tunneling. The chain is driven by the superposition of dc and ac fields in the strong coupling regime. Based on the fundamental principles of electrodynamics and quantum theory, we developed a generalized model of quantum dynamics for such interactions, free of rotating wave approximation (RWA). The system of motion equations was studied numerically. We analyzed the dynamics and spectra of inversion density, dipole current density and tunneling current density. In the case of resonant interaction with accomponent the particle dynamics exhibits itself in the oscillatory regime, which may be interpreted as a combination of Rabi-and Bloch oscillations with their strong mutual influence. Such scenario for an obliquely incident ac field dramatically differs from the individual picture both types of oscillations due to an interactions. This novel effect is counterintuitive because of the strongly different frequency ranges for such two types of oscillations existence. This dynamics manifests itself in multi-line spectra at different combinations of Rabi-and Bloch frequencies. The effect is promising as a framework of new type of spectroscopy in nanoelectronics and electrical control of nano-devices.PACS number(s): 73.40.Gk

Abstract:We considered one-dimensional quantum chains of two-level Fermi particles coupled via the tunneling driven both by ac and dc fields in the regimes of strong and ultrastrong coupling. The frequency of ac field is matched with the frequency of the quantum transition. Based on the fundamental principles of electrodynamics and quantum theory, we developed a general model of quantum dynamics for such interactions. We showed that the joint action of ac and dc fields leads to the strong mutual influence of Rabi-and Bloch oscillations, one to another. We focused on the regime of ultrastrong coupling, for which Bloch-and Rabi-frequencies are significant values of the frequency of interband transition. The Hamiltonian was solved numerically, with account of anti-resonant terms. It manifests by the appearance of a great number of narrow high-amplitude resonant lines in the spectra of tunneling current and dipole moment. We proposed the new concept of terahertz (THz) spectroscopy, which is promising for different applications in future nanoelectronics and nano-photonics.

We present the model of one-dimensional chain of two-level artificial atoms driven with dc field and quantum light simultaneously in strong coupling regime. The interaction of atoms with light leads to entanglement of electron and photon states (dressing of the atoms). The driving via dc field leads to the Bloch oscillations (BO) in the chain of dressed atoms. We considered the mutual influence of dressing and BO and show that scenario of oscillations dramatically differs from predicted by the Jaynes-Cummings and Bloch-Zener models. We study the evolution of the population inversion, tunneling current, photon probability distribution, mean number of photons, photon number variance and show the influence of BO on the quantum-statistical characteristics of light. For example, collapse-revivals picture and vacuum Rabi-oscillations are strongly modulated with Bloch frequency. As a result, quantum properties of light and degree of electron-photon entanglement become controllable via adiabatic dc field turning. On the other hand, the low-frequency tunneling current depends on the quantum light statistics (in particular, for coherent initial state it is modulated accordingly the collapserevivals picture). The developed model is universal with respect to the physical origin of artificial atom and frequency range of atom-light interaction. The model is adapted to the 2D-heterostructures (THz frequencies), semiconductor quantum dots (optical range), and Josephson junctions (microwaves). The data for numerical simulations are taken from recently published experiments. The obtained results open a new ways in quantum state engineering and nano-photonic spectroscopy. I.In this paper, we build a theoretical model of a chain of coupled two-level quantum elements exposed to the quantum light and driven via bias voltage. We consider the case of strong coupling of light with charge carriers, which leads to the entanglement of electron-photon quantum states. This model describes BO of electrons dressed with light and their mutual influence with RO. Our model has a significant degree of generality: it relates to the systems of different physical origin and various frequency ranges. We consider its application to semiconductor heterostructures (THz frequencies), semiconductor quantum dots (visible frequencies), Josephson junctions (microwaves). For brevity, we refer to every of these artificial two-level quantum objects as an "atom" regardless of its physical implementation.We develope the model taking into account conditions of real experiments. For example, the coherent intersubband excitation of heterostructure in THz region has been done in [50] by the ultrashort (femtosecond) pulses. On this account, we generalized our model for the case of electromagnetic pulse, advancing the secondary quantization of fields to the case of pulses. Our model is based on some conventional simplifications. We use rotating-wave approximation (RWA) and neglect any damping. This requires the fulfillment of certain relations between the frequencies (tr...

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