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## Semion formalism for spin and qubit systems: Non-Markovian treatment

Physical Review A: Atomic, Molecular, and Optical physics. 2020. Vol. 102. No. 3. Article 042224.

Using semion substitution for spin variables we perform an *ab initio* derivation of effective action for an open quantum two-level system . For this purpose, we introduce, by using the Hubbard-Stratonovich transformation a two-time complex quantum field which average value plays the role of the Green's function for the spin variables. The field thus introduced allows us to develop a diagram technique in a standard way. The proposed formalism is used to study a spin embedded into an Ohmic reservoir as an example of the spin-boson model. Non-Markovian effects in this system are analyzed.

Aleiner I. L., Faoro L., Ioffe L., Annals of Physics 2016 Vol. 375 P. 378-406

We extend the Keldysh technique to enable the computation of out-of-time order correlators such as 〈O(t)Õ(0)O(t)Õ(0)〉. We show that the behavior of these correlators is described by equations that display initially an exponential instability which is followed by a linear propagation of the decoherence between two initially identically copies of the quantum many body systems ...

Added: October 21, 2016

Cosacchi M., Seidelmann T., Cygorek M. et al., Physical Review Letters 2021 Vol. 127 No. 10 Article 100402

The quantum regression theorem (QRT) is the most widely used tool for calculating multitime correlation functions for the assessment of quantum emitters. It is an approximate method based on a Markov assumption for environmental coupling. In this Letter we quantify properties of photons emitted from a single quantum dot coupled to phonons. For the single-photon ...

Added: September 26, 2021

Komrakova S., Javadzade J., Vorobyov V. et al., Journal of Physics: Conference Series 2019 Vol. 1410 Article 012180

Here we demonstrate CMOS compatible method to deterministically produce
nanoantenna with nanodiamonds systems on the example of a bull-eye antenna on top of on
hyperbolic metamaterials. We study the statistics of the placement of nanodiamonds and
measure the fluorescence lifetime and the second-order correlation function of NV-centers
inside nanodiamonds. ...

Added: April 28, 2021

Sergeev T., Zyablovsky A., Andrianov E. et al., Scientific Reports 2021 Vol. 11 Article 24054

We demonstrate a new type of non-Hermitian phase transition in open systems far from thermal equilibrium, which can have place in the absence of an exceptional point. This transition takes place in coupled systems interacting with reservoirs at different temperatures. We show that the spectrum of energy flow through the system caused by the temperature ...

Added: January 2, 2022

Mokhnenko S., Kamenski A. A., Ovsiannikov V. D., European Physical Journal D 2018 Vol. 72 No. 28

An asymptotic expression for the van-der-Waals constant C6(n) ≈ –0.03n12K p (x) is derived for the long-range interaction between two highly excited hydrogen atoms A and B in their extreme Stark states of equal principal quantum numbers n A = n B = n ≫ 1 and parabolic quantum numbers n1(2) = n - 1, n2(1) = m = 0 in the case of collinear orientation of the Stark-state dipolar electric moments and the interatomic ...

Added: December 24, 2020

Remizov S., Zhukov A. A., Шапиро Д. С. et al., Journal of Physics: Conference Series 2018 Vol. 1092 Article 012123

A qubit system coupled to a resonator may be treated as a quantum metamaterial. Quantum nature of such a system results in large variety of non-trivial effects. In particular, we study a parametrically driven system of qubits coupled to a single-mode resonator and show that the energy dissipation in the resonator can enhance population of ...

Added: October 29, 2021

Fedorov G. P., Remizov S., Шапиро Д. С. et al., Physical Review Letters 2021 Vol. 126 Article 180503

We demonstrate nonequilibrium steady-state photon transport through a chain of five coupled artificial atoms simulating the driven-dissipative Bose-Hubbard model. Using transmission spectroscopy, we show that the system retains many-particle coherence despite being coupled strongly to two open spaces. We find that cross-Kerr interaction between system states allows high-contrast spectroscopic visualization of the emergent energy bands. ...

Added: October 29, 2021

Cosacchi M., Seidelmann T., Wiercinski J. et al., Physical Review Research 2021 Vol. 3 No. 2 Article 023088

A Schrödinger-cat state is a coherent superposition of macroscopically distinguishable quantum states, in quantum optics usually realized as superposition of coherent states. Protocols to prepare photonic cats have been presented for atomic systems. Here we investigate in what manner and how well the preparation protocols can be transferred to a solid-state platform, namely, a semiconductor ...

Added: September 26, 2021

Duplinskiy A., Sych D., Physical Review A: Atomic, Molecular, and Optical physics 2021 Vol. 104 No. 1 Article 012601

Passive side-channel attacks in quantum key distribution (QKD) aim at obtaining information about the quantum signals without disturbing them and hence compromise real-world QKD security. Currently, there are no reliable tools for the assessment of QKD signal generation imperfections. In this work we propose a generic experimental method which allows to upper-bound QKD light-source imperfections ...

Added: October 8, 2021

Boulatov A., Burin A. L., Journal of Chemical Physics 2020 Vol. 153 No. 13 P. 134102

The low temperature transport of electron, or vibrational or electronic exciton towards polymer chains turns out to be dramatically sensitive to its interaction with transverse acoustic vibrations. We show that this interaction leads to substantial polaron eﬀect and decoherence, which are generally stronger than those associated with longitudinal vibrations. For site-dependent interactions transverse phonons form subohmic bath leading to ...

Added: October 14, 2020

Zhukov A. A., Remizov S., Погосов В. В. et al., JETP Letters 2018 Vol. 108 No. 1 P. 63-70

It has been shown that superconducting qubit systems, having high tunability, can be used as a platform for the experimental study of various effects of nonstationary quantum electrodynamics in a cavity. In particular, the dynamic Lamb effect can be implemented owing to a nonadiabatic change in the effective coupling between the subsystem of qubits and ...

Added: October 29, 2021

Vladimirova Y. V., Zadkov V., NANOMATERIALS 2021 Vol. 11 No. 8 P. 1-33

This review is devoted to the study of effects of quantum optics in nanostructures. The mechanisms by which the rates of radiative and nonradiative decay are modified are considered in the model of a two-level quantum emitter (QE) near a plasmonic nanoparticle (NP). The distributions of the intensity and polarization of the near field around ...

Added: July 26, 2021

Remizov S., Zhukov A. A., Шапиро Д. С. et al., Journal of Low Temperature Physics 2018 Vol. 191 P. 365-372

We consider a parametrically driven system of a qubit coupled to a cavity taking into account different channels of energy dissipation. We focus on the periodic modulation of a single parameter of this hybrid system, which is the coupling constant between the two subsystems. Such a modulation is possible within the superconducting realization of qubit–cavity ...

Added: October 29, 2021

Mokhnenko S., Kamenski A. A., Manakov N. L. et al., Physical Review A: Atomic, Molecular, and Optical physics 2017 Vol. 96 P. 032716

The van der Waals coefficient C6(θ;nlJM) of two like Rydberg atoms in their identical Rydberg states |nlJM⟩ is resolved into four irreducible components called scalar Rss, axial (vector) Raa, scalar-tensor RsT=RTs, and tensor-tensor RTT parts in analogy with the components of dipole polarizabilities. The irreducible components determine the dependence of C6(θ;nlJM) on the angle θ between the interatomic and the quantization axes of atoms. The spectral resolution for ...

Added: December 24, 2020

Mokhnenko S., Овсянников В. Д., Мармо С. И. et al., Квантовая электроника 2017 Т. 47 № 5 С. 412

Разработка оптических стандартов частоты с относительной неопределенностью воспроизведения единиц времени и частоты 10-17 – 10-18 требует беспрецедентной точности при оценке роли высших порядков оптической нелинейности, обусловленных влиянием оптической решетки на сдвиг частоты "часового перехода". В настоящей статье проведен систематический расчет вкладов мультипольных нелинейных ангармонических эффектов в погрешность часов на основе оптических решеток для щелочно-земельно-подобных атомов Sr, Yb ...

Added: December 24, 2020

Remizov S., Шапиро Д. С., Rubtsov A. N., JETP Letters 2017 Vol. 105 P. 130-136

We study quantum effects of strong driving field applied to dissipative hybrid qubit-cavity system which are relevant for a realization of quantum gates in superconducting quantum metamaterials. We demonstrate that effects of strong and non-stationary drivings have significantly quantum nature and cannot be treated by means of mean-field approximation. This is shown from a comparison ...

Added: October 29, 2021

Bell M. T., Paramanandam J., Ioffe L. et al., Physical Review Letters 2014 Vol. 112 P. 167001

Added: October 21, 2016

Mokhnenko S., Kamenski A. A., Ovsiannikov V. D., undefined 2017 Vol. 1 No. 1 P. 015006

Added: December 24, 2020

Шапиро Д. С., Погосов В. В., Lozovik Y., Physical Review A: Atomic, Molecular, and Optical physics 2020 Vol. 102 No. 2 Article 023703

In view of recent proposals for the realization of anisotropic light-matter interaction in such platforms as (i) nonstationary or inductively and capacitively coupled superconducting qubits, (ii) atoms in crossed fields, and (iii) semiconductor heterostructures with spin-orbital interaction, the concept of a generalized Dicke model, where coupling strengths of rotating wave and counter-rotating wave terms are ...

Added: October 31, 2021

Springer, 2019

This book brings together reviews by internationally renowed experts on quantum optics and photonics. It describes novel experiments at the limit of single photons, and presents advances in this emerging research area. It also includes reprints and historical descriptions of some of the first pioneering experiments at a single-photon level and nonlinear optics, performed before the inception ...

Added: May 14, 2019

Komrakova S., Javadzade J., Vorobyov V. et al., Journal of Physics: Conference Series 2018 Vol. 1124 No. 5 Article 051046

Here we studied the fabrication technique of a kilopixel array of nanodiamonds with
a nitrogen-vacancy color centers (NV) on top of the chip and measured the second-order
correlation function deep, clearly demonstrated the presence of single-photon sources. The
controlled position of nanodiamonds, determined from the measurement of second-order
correlation function was realized, as well as the yield of optimized ...

Added: April 28, 2021

Bolshedvorskii S., Vorobyov V., Soshenko V. et al., Optical Materials Express 2017 Vol. 7 No. 11 P. 4038-4049

In this paper, we experimentally investigate optical and spin properties of NV centers in aggregates of detonation nanodiamonds. We show that despite the small size of nanodiamonds forming the aggregate, the NV centers in these aggregates exhibit spin properties comparable to similar size nanodiamonds grown by other methods, but with brightness enhanced by a factor ...

Added: April 28, 2021

Remizov S., Zhukov A. A., Шапиро Д. С. et al., Physical Review A: Atomic, Molecular, and Optical physics 2017 Vol. 96 No. 4 Article 043870

We consider a dissipative evolution of a parametrically driven qubit-cavity system under the periodic modulation of coupling energy between two subsystems, which leads to the amplification of counter-rotating processes. We reveal a very rich dynamical behavior of this hybrid system. In particular, we find that the energy dissipation in one of the subsystems can enhance ...

Added: October 29, 2021

Komrakova S., Kovalyuk V., An P. et al., Journal of Physics: Conference Series 2020 Vol. 1695 No. 1 Article 012135

In this paper, we demonstrate the results of a study of the optical absorption
properties of graphene integrated with silicon nitride O-ring resonator. We fabricated an array
of O-ring resonators with different graphene coverage area atop. By measuring the
transmission spectra of nanophotonic devices with and without graphene, we calculated the
effective absorption coefficient of the graphene on a ...

Added: April 28, 2021