Related papers: Spectral function and fidelity susceptibility in q…
Coherence and correlation are key features of the quantum system. Quantifying these quantities are astounding task in the framework of resource theory of quantum information processing. In this article, we identify an affinity-based metric…
Fidelity is a figure of merit widely employed in quantum technology in order to quantify similarity between quantum states and, in turn, to assess quantum resources or reconstruction techniques. Fidelities higher than, say, 0.9 or 0.99, are…
We obtained the spectral function of the graphite H point using high resolution angle resolved photoelectron spectroscopy (ARPES). The extracted width of the spectral function (inverse of the photo-hole lifetime) near the H point is…
We discuss the infrared and ultraviolet behavior of the fermion propagator in (2+1)-dimensional QED based on spectral representation.If we choose soft-photon exponentiation to include all orders of soft-photon emission by electron,its…
We calculate the real and imaginary electron self-energy as well as the quasiparticle spectral function in doped graphene taking into account electron-electron interaction in the leading order dynamically screened Coulomb coupling. Our…
We calculate the fidelity susceptibility chi_f for the Luttinger model and show that there is a universal contribution linear in temperature T (or inverse length 1/L). Furthermore, we develop an algorithm - based on a lattice path integral…
It was shown via numerical simulations that geometric phase (GP) and fidelity susceptibility (FS) in some quantum models exhibit universal scaling laws across phase transition points. Here we propose a singular function expansion method to…
We propose a fidelity measure for quantum channels in a straightforward analogy to the corresponding mixed-state fidelity of Jozsa. We describe properties of this fidelity measure and discuss some applications of it to quantum information…
The spectral function of 4He is calculated with the Lorentz integral transform method in a large energy and momentum range. The excitation spectrum of the residual 3N-system is fully taken into account. The obtained spectral function is…
This paper is a continuation of my previous work on absolutely continuous and singular spectral shift functions, where it was in particular proved that the singular part of the spectral shift function is an a.e. integer-valued function. It…
The ICARUS and future liquid argon neutrino experiments generate demand for evaluating the spectral function of argon. In this paper we use oxygen nucleus as a testing ground for our phenomenological approach to the spectral function and…
We explicitly calculate information, fidelity, and reversibility of an arbitrary single-qubit measurement on a completely unknown state. These quantities are expressed as functions of a single parameter, which is the ratio of the two…
The shape function f(k_+) describes Fermi motion effects in inclusive semi-leptonic decays such as B -> X_u+e+nu near the end-point of the lepton spectrum. We compute the leading one-loop corrections to the shape function f(k_+) in the…
We derive a simple analytical formula to describe the evolution of spectral index $\beta$ in the steep decay phase shaped by the curvature effect with assumption that the spectral parameters and Lorentz factor of jet shell is the same for…
We study the role of the electromagnetic field's frequency in time precision measurements using single photons as a paradigmatic system. For such, we independently identify the contributions of intensity and spectral resources and show that…
We study momentum-resolved tunneling into a system of spinless chiral one-dimensional fermions, such as electrons at the edge of an integer quantum Hall system. Interactions between particles give rise to broadening of the spectral function…
We develop the theory of continuous-variable quantum secret sharing and propose its interferometric realization using passive and active optical elements. In the ideal case of infinite squeezing, a fidelity ${\cal F}$ of unity can be…
We address characterization of many-body superradiant systems and establish a fundamental connection between quantum criticality and the possibility of locally estimating the coupling constant, i.e extracting its value by probing only a…
The Herschel SPIRE Fourier transform spectrometer (FTS) performs spectral imaging in the 447-1546 GHz band. It can observe in three spatial sampling modes: sparse mode, with a single pointing on sky, or intermediate or full modes with 1 and…
The spectral envelope S(F) of a subset of integers is the set of probability measures on the circle group that are weak star limits of squared moduli of trigonometric polynomials with frequencies in F. Fourier transforms of these measures…