Nonreciprocal two-photon transmission and statistics in the chiral waveguide QED system

We study the nonreciprocal properties of transmitted photons in the chiral waveguide QED system, including single- and two-photon transmissions and second-order correlations. For the single-photon transmission, the nonreciprocity is induced by the effects of chiral coupling and atomic dissipation in the weak coupling region. It vanishes in the strong coupling regime when the effect of atomic dissipation becomes ignorable. In the case of two-photon transmission, there exist two ways of going through the emitter: independently as plane waves and formation of bound state. Besides the nonreciprocal behavior of plane waves, the bound state that differs in two directions also alters transmission probabilities. In addition, the second-order correlation of transmitted photons depends on the interference between plane wave and bound state. The destructive interference leads to the strong antibunching in the weak coupling region, while the effective formation of bound state leads to the strong bunching in the intermediate coupling region. However, the negligible interactions for left-propagating photons hardly change the statistics of the input coherent state.

ℳcTEQ (ℳ chiral perturbation theory-compatible deconfinement Temperature and Entanglement Entropy up to terms Quartic in curvature) and FM (Flavor Memory)

A (semiclassical) holographic computation of the deconfinement temperature at intermediate coupling from (a top-down) ℳ-theory dual of thermal QCD-like theories, has been missing in the literature. In the process of filling this gap, we demonstrate a novel UV-IR connection, (conjecture and provide evidence for) a non-renormalization beyond one loop of ℳ-chiral perturbation theory [1]-compatible deconfinement Temperature, and show equivalence with an Entanglement (as well as Wald) entropy [2] computation, up to terms Quartic in curvature (R). We demonstrate a Flavor-Memory (FM) effect in the ℳ-theory uplifts of the gravity duals, wherein the no-braner ℳ-theory uplift retains the “memory” of the flavor D7-branes of the parent type IIB dual in the sense that a specific combination of the aforementioned quartic corrections to the metric components precisely along the compact part (given by S3 as an S1-fibration over the vanishing two-cycle S2) of the non-compact four-cycle “wrapped” by the flavor D7-branes, is what determines, e.g., the Einstein-Hilbert action at O(R4). The aforementioned linear combination of 𝒪(R4) corrections to the ℳ-theory uplift [3, 4] metric, upon matching the holographic result from ℳχPT [1] with the phenomenological value of the coupling constant of one of the SU(3) NLO χPT Lagrangian of [5], is required to have a definite sign. Interestingly, in the decompactification (or “MKK → 0”) limit of the spatial circle in [1] to recover a QCD-like theory in four dimensions after integrating out the compact directions, we not only derive this, but in fact obtain the values of the relevant 𝒪(R4) metric corrections. Further, equivalence with Wald entropy for the black hole in the high-temperature ℳ-theory dual at 𝒪(R4) imposes a linear constraint on a similar linear combination of the abovementioned metric corrections. Remarkably, when evaluating the deconfinement temperature from an entanglement entropy computation in the thermal gravity dual, due to a delicate cancellation between the contributions arising from the metric corrections at 𝒪(R4) in the ℳ theory uplift along the S1-fiber and an S2 (which too involves a similar S1-fibration) resulting in a non-zero contribution only along the vanishing S2 surviving, one sees that there are consequently no corrections to Tc at quartic order in the curvature supporting the conjecture made on the basis of a semiclassical computation.

Spheres to jets tuning event shapes with 5d simplified models

Hidden sectors could give rise to a wide variety of events at the LHC. Confining hidden sectors are known to engender events with a small number of jets when they are weakly-coupled at high energies, and quasi-spherical soft unclustered energy patterns (SUEPs) when they are very strongly-coupled (large ‘t Hooft coupling) at high energies. The intermediate regime is murky, and could give rise to signals hiding from existing search strategies. While the intermediate coupling regime is not calculable, it is possible to pursue a phenomenological approach in which one creates signals that are intermediate between spherical and jetty. We propose a strategy for generating events of this type using simplified models in extra dimensions. The degree to which the event looks spherical is related to the number of decays produced near kinematic threshold. We provide an analytic understanding of how this is determined by parameters of the model. To quantify the shape of events produced with this model, we use a recently proposed observable — event isotropy — which is a better probe of the spherical regime than earlier event shape observables.

Calculation of the position of spectral lines in the intermediate coupling approximation taking into account the interaction of configurations

When modeling experimental spectra, special attention is paid to the accuracy of the position of spectral lines, which in many-electron ions depends not only on the spin-orbital and electrostatic interaction, but also on the interaction of configurations. In order to improve the THERMOS complex on the basis of an intermediate-type bond, a module was developed that uses the Ritz method to calculate the splitting of ion levels due to the spin-orbit interaction, taking into account the interaction of configurations. Comparisons of the results obtained for lithium and iron plasma are made.

Радиационные константы в спектре иона W VII

Radiative transition probabilities 4f135p66p + 4f145p56p - 4f136s, 4f137s, and 4f137s levels lifetimes for erbium-like W VII were calculated smiempirically in intermediate coupling scheme using experimental energy levels. Radial transition integrals were derived in length form with Hartree-Fock functions.

A Numerically Exact Method for Dissipative Dynamics of Qubits

We propose a numerical technique suitable for simulating the dynamics of reduced density matrix of a qubit interacting with its environment. Our approach, based on a combination of short-iterative Lanczos method (SIL) and a flexible truncation scheme, allows to include in the physical description multiple-excitation processes, beyond weak coupling and Markov approximations. We perform numerical simulations of two different model Hamiltonians, that are relevant in the field of adiabatic quantum computation (AQC), and we show that our technique is able to recover the correct thermodynamic behavior of the qubit-bath system, from weak to intermediate coupling regime.

Orthogonal Operators: Applications, Origin and Outlook

Orthogonal operators can successfully be used to calculate eigenvalues and eigenvector compositions in complex spectra. Orthogonality ensures least correlation between the operators and thereby more stability in the fit, even for small interactions. The resulting eigenvectors are used to transform the pure transition matrix into realistic intermediate coupling transition probabilities. Calculated transition probabilities for close lying levels illustrate the power of the complete orthogonal operator approach.

Orthogonal Operators: Applications, Origin and Outlook

Orthogonal operators can successfully be used to calculate eigenvalues and eigenvector compositions in complex spectra. Orthogonality ensures least correlation between the operators and thereby more stability in the fit, even for small interactions. The resulting eigenvectors are used to transform the pure transition matrix into realistic intermediate coupling transition probabilities. Calculated transition probabilities for close lying levels illustrate the power of the complete orthogonal operator approach.