English
Related papers

Related papers: On a new method to analyse QSO spectra

200 papers

We argue that the claimed optimality of a new process tomography method suggested in [quant-ph/0601033] and [quant-ph/0601034] is based on not completely fair comparison that does not take into account the available information in an equal…

Quantum Physics · Physics 2007-05-23 Mario Ziman

An algorithm is presented which generates pairs of oscillatory random time series which have identical periodograms but differ in the number of oscillations. This result indicate the intrinsic limitations of spectral methods when it comes…

Data Analysis, Statistics and Probability · Physics 2007-05-23 A. G. Rossberg

While Spectral Methods have long been used for Principal Component Analysis, this survey focusses on work over the last 15 years with three salient features: (i) Spectral methods are useful not only for numerical problems, but also discrete…

Data Structures and Algorithms · Computer Science 2010-04-09 Ravindran Kannan

An efficient despeckling method using a quantum-inspired adaptive threshold function is presented for reducing noise of ultrasound images. In the first step, the ultrasound image is decorrelated by an spectrum equalization procedure due to…

Computer Vision and Pattern Recognition · Computer Science 2018-07-10 Hamid Reza Shahdoosti

The analysis of signals created by a variety of instruments involves calculating the phase of a sinusoidal type signal. One widely used method to extract this information is through the use of Fourier transforms, but it is known that…

Optics · Physics 2018-11-02 Andrew John Henning , Dawei Tang , Xiangqian , Jiang

We present a complete methodology for testing the performances of quantum tomography protocols. The theory is validated by several numerical examples and by the comparison with experimental results achieved with various protocols for whole…

Quench spectroscopy has emerged as a novel and powerful technique for probing the energy spectrum of various quantum phases for quantum systems from out-of-equilibrium dynamics. While its efficacy has been demonstrated in the homogeneous…

Quantum Gases · Physics 2025-11-25 Jiachen Yu , Yuanzhe Hu , Wenhan Chen , Jianing Yang , Xuzong Chen , Hepeng Yao

In this comment we show that the approach presented by Foj\'on et al~\cite{Fojon10} is not as accurate as they claim. A straightforward calculation using the models considered buy those authors clearly shows that the spectral method, which…

Quantum Physics · Physics 2018-10-29 Miguel Ahumada-Centeno , Paolo Amore , Francisco M Fernandez

Measurement of the energy eigenvalues (spectrum) of a multi-qubit system has recently become possible by qubit tunneling spectroscopy (QTS). In the standard QTS experiments, an incoherent probe qubit is strongly coupled to one of the qubits…

Quantum Physics · Physics 2018-02-22 Anatoly Yu. Smirnov , Mohammad H. Amin

The extension of piezoresistance coefficient extraction method was proposed, for protection from errors in estimation of the thickness of the test structure membrane. This new approach requires finding models of elements of matrix of…

Mesoscale and Nanoscale Physics · Physics 2016-01-11 Zenon Gniazdowski , Bogdan Latecki , Pawel Kowalski

We develop an alternative approach to time independent perturbation theory in non-relativistic quantum mechanics. The method developed has the advantage to provide in one operation the correction to the energy and to the wave function,…

Quantum Physics · Physics 2013-03-13 J. Martinez-Carranza , F. Soto-Eguibar , H. Moya-Cessa

In quantum logic spectroscopy (QLS), one species of trapped ion is used as a sensor to detect the state of an otherwise inaccessible ion species. This extends precision measurements to a broader class of atomic and molecular systems for…

Atomic Physics · Physics 2022-11-16 Kaifeng Cui , Jose Valencia , Kevin T. Boyce , David R. Leibrandt , David B. Hume

A means to extract the fine-structure constant $\alpha$ from precision spectroscopic data on one-electron ions is presented. We show that in an appropriately weighted difference of the bound-electron $g$ factor and the ground state energy,…

Atomic Physics · Physics 2020-06-26 H. Cakir , N. S. Oreshkina , I. A. Valuev , V. Debierre , V. A. Yerokhin , C. H. Keitel , Z. Harman

We zoom in on the internal structure of the low-frequency quasi-periodic oscillation (LF QPO) often observed in black hole binary systems to investigate the physical nature of the lack of coherence in this feature. We show the limitations…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Pawel Lachowicz , Chris Done

Context: The technique of disentangling has been applied to numerous high-precision studies of spectroscopic binaries and multiple stars. Although, its possibilities have not yet been fully understood and exploited. Aims: Theoretical…

Instrumentation and Methods for Astrophysics · Physics 2009-11-13 Petr Hadrava

Recently, a new signal analysis method based on a semi-classical approach has been proposed [1]. The main idea in this method is to interpret a signal as a potential of a Schrodinger operator and then to use the discrete spectrum of this…

Numerical Analysis · Mathematics 2012-09-03 Da-Yan Liu , Taous-Meriem Laleg-Kirati

New methods are proposed to characterize the spectral-temporal distribution of single photons. The presented protocols take advantage of spectral filtering, frequency entanglement between two single photons the one of interest and a…

Quantum Physics · Physics 2022-06-29 Nicolas Fabre

Qubit noise spectroscopy is an important tool for the experimental investigation of open quantum systems. However, conventional techniques for noise spectroscopy are time-consuming, because they require measurements of the noise spectral…

Quantum Physics · Physics 2025-06-24 Kaixin Huang , Demitry Farfurnik , Alireza Seif , Mohammad Hafezi , Yi-Kai Liu

A novel operational method for estimating the efficiency of quantum state tomography protocols is suggested. It is based on a-priori estimation of the quality of an arbitrary protocol by means of universal asymptotic fidelity distribution…

Quantum Physics · Physics 2015-05-18 Yu. I. Bogdanov , G. Brida , M. Genovese , S. P. Kulik , E. V. Moreva , A. P. Shurupov

Searches for spacetime variations of fundamental constants have entered an era of unprecedented precision. New, high quality quasar spectra require increasingly refined analytic methods. In this article, a continuation in a series to…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-03 John K. Webb , Chung-Chi Lee