Signatures of many-body localization in steady states of open quantum systems

Many-body localization (MBL) is a result of the balance between interference-based Anderson localization and many-body interactions in an ultra-high dimensional Fock space. It is usually expected that dissipation is blurring interference and destroying that balance so that the asymptotic state of a system with an MBL Hamiltonian does not bear localization signatures. We demonstrate, within the framework of the Lindblad formalism, that the system can be brought into a steady state with non-vanishing MBL signatures. We use a set of dissipative operators acting on pairs of connected sites (or spins), and show that the difference between ergodic and MBL Hamiltonians is encoded in the imbalance, entanglement entropy, and level spacing characteristics of the density operator. An MBL system which is exposed to the combined impact of local dephasing and pairwise dissipation evinces localization signatures hitherto absent in the dephasing-outshaped steady state.Comment: 6 pages, 3 figure

Photon waiting time distributions: a keyhole into dissipative quantum chaos

Open quantum systems can exhibit complex states, which classification and quantification is still not well resolved. The Kerr-nonlinear cavity, periodically modulated in time by coherent pumping of the intra-cavity photonic mode, is one of the examples. Unraveling the corresponding Markovian master equation into an ensemble of quantum trajectories and employing the recently proposed calculation of quantum Lyapunov exponents [I.I. Yusipov {\it et al.}, Chaos {\bf 29}, 063130 (2019)], we identify `chaotic' and `regular' regimes there. In particular, we show that chaotic regimes manifest an intermediate power-law asymptotics in the distribution of photon waiting times. This distribution can be retrieved by monitoring photon emission with a single-photon detector, so that chaotic and regular states can be discriminated without disturbing the intra-cavity dynamics.Comment: 7 pages, 5 figure

Influence of topological excitations on Shapiro steps and microwave dynamical conductance in bilayer exciton condensates

The quantum Hall state at total filling factor $\nu_T=1$ in bilayer systems realizes an exciton condensate and exhibits a zero-bias tunneling anomaly, similar to the Josephson effect in the presence of fluctuations. In contrast to conventional Josephson junctions, no Fraunhofer diffraction pattern has been observed, due to disorder induced topological defects, so-called merons. We consider interlayer tunneling in the presence of microwave radiation, and find Shapiro steps in the tunneling current-voltage characteristic despite the presence of merons. Moreover, the Josephson oscillations can also be observed as resonant features in the microwave dynamical conductance

Dynamic equations for three different qudits in a magnetic field

A closed system of equations for the local Bloch vectors and spin correlation functions of three magnetic qudits, which are in an arbitrary, time-dependent, external magnetic field, is obtained using decomplexification of the Liouville-von Neumann equation. The algorithm of the derivation of the dynamic equations is presented. In the basis convenient for the important physical applications structure constants of algebra su(2S+1) are calculated.Comment: 11 page

Pathomorphological features of the uterus’ wall structure in case of fetuses with a gestational term of 37-40 weeks from mothers with a chronic infection of the lower genital tracts

In the following article we have provided a data towards a comprehensive research of the pathomorphological features of the uterus’ wall structure in case of fetuses from mothers with HILGT comparing to ones in case of fetuses from healthy mothers. The research methods: macroscopic, organometric, histological, immunohistochemical, morphometric, statistical. On the basis of the organometric research we have revealed a probable decrease of the weight, length and thickness indexes likewise one of the main components of the uterus wall in case of fetuses from mothers with a complicated pregnancy comparing to ones in case of fetuses from healthy mothers. By applying histological method we have revealed an increased growth of the connective tissue both in the endometrium and myometrium in case of fetuses from mothers with HILGT relatively to one in case of fetuses from mothers with a physiological pregnancy. Moreover, the massive growth of the collagen fibers leads to the disorder in the strucutral organization of the muscle component. The uterus’ endometrium in case of fetuses from the main group could be characterized by a few glands without features of the functional activity comparing to one in case of fetuses from the group of comparison. In the structure of the connective tissue in case of uterus of fetuses from mothers with a complicated pregnancy we have revealed mainly the collagen of the III type, while the collagen of the I type could be revealed in the form of small loci of reduced intensity of glow. By applying the immunohistochemical method we have revealed an increase of the apoptotic index in the endometrium of fetuses from mothers with a chronic infection of the lower genital tracts comparing to one in case of fetuses from healthy mothers. By applying MCAT to endotheline-1 we have revealed an increased glow of the endtheliocytes in the vessels both of arterial and venous types, in case of fetuses from the main group comparing to one in case of fetuses from the group of comparison. In the uterus of fetuses from mothers with HILGT we could observe a decreased hormon producing activity comparing to one in case of fetuses from mothers with a physiological pregnancy. All changes, that were revealed in the uterus of fetuses from mothers with an infectious pathlogy declare an existance of the severe disorder in the implementation and formation of main organ’s components, as well as are caused mainly by a chronic hypoxia as well as influence of the infectious agent. All pathomorphological features of the uterus wall structure in case of fetuses from mothers with HILGT, that were revealed, could contribute subsequently to the complications in the pregnancy’s onset as well as could lead to the disruption of one