Kramers–Kronig relations ≈ Kramers–Kronig relations
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Kramers–Kronig coherent receiver Open
The interest for short-reach links of the kind needed for inter-data-center communications has fueled in recent years the search for transmission schemes that are simultaneously highly performing and cost effective. In this work we propose…
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Use of x-ray scattering functions in Kramers-Kronig analysis of reflectance Open
Kramers-Kronig analysis is commonly used to estimate the optical properties of new materials. The analysis typically uses data from far infrared through near ultraviolet (say, 40--40,000 cm$^{-1}$ or 5 mev--5 eV) and uses extrapolations ou…
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Measuring the optical permittivity of two-dimensional materials without <i>a priori</i> knowledge of electronic transitions Open
We propose a deterministic method to measure the optical permittivity of two-dimensional (2D) materials without a priori knowledge of the electronic transitions over the spectral window of interest. Using the thin-film approximation, we sh…
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Optical constants and dynamic conductivities of single layer MoS2, MoSe2, and WSe2 Open
The complex optical constants of single layer MoS2, MoSe2, and WSe2 transition metal dichalcogenides (TMDCs) have been measured using concerted frequency-dependent transmittance and reflectance measurements. Absolute absorptivities as well…
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Beer's Law‐Why Integrated Absorbance Depends Linearly on Concentration Open
As derived by Max Planck in 1903 from dispersion theory, Beer's law has a fundamental limitation. The concentration dependence of absorbance can deviate from linearity, even in the absence of any interactions or instrumental nonlinearities…
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Functional analysis of the polarization response in linear time-varying media: A generalization of the Kramers-Kronig relations Open
We explore the mathematical theory to rigorously describe the response of\nmedia with linear time-varying, generally dispersive, electromagnetic\nconstitutive parameters. We show that even when the temporal inhomogeneity\ntakes place on a …
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Observation of reflectionless absorption due to spatial Kramers–Kronig profile Open
As a fundamental phenomenon in electromagnetics and optics, material absorption has been extensively investigated for centuries. However, omnidirectional, reflectionless absorption in inhomogeneous media has yet to be observed. Previous re…
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Quantitative analysis of diffraction and infra-red spectra of composite cement/BaSO4/Fe3O4 for determining correlation between attenuation coefficient, structural and optical properties Open
To better understand the structural and optical properties of composite cement/BaSO4/Fe3O4 for various amount of BaSO4/Fe3O4, the X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy have been used to investigate the …
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Application of the Kramers–Kronig Relations to Multi-Sine Electrochemical Impedance Measurements Open
Impedance spectra obtained by fast Fourier transformation of the response to a multi-sine potential perturbation are shown to be consistent with the Kramers–Kronig relations, even for systems that are nonlinear and nonstationary. These res…
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Wave reflection in dielectric media obeying spatial Kramers-Kronig relations Open
In a recent work, Horsley and coworkers (
\nNat. Photon.
\n,
\n9
\n(2015) 436) showed rather
\ninterestingly that planar dielectric media, for which the real and imaginary parts of the dielectric
\npermittivity are related by spatial Krame…
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Structural and Optical Coefficients Investigation of γ-Al2O3 Nanoparticles using Kramers-Kronig Relations and Z–scan Technique Open
γ-Al2O3 nanoparticles (NPs) with a mean diameter of 60 nm were prepared through the sol–gel technique and characterized by X-ray diffraction, field emission scanning electron microscopy (FESEM), and ultraviolet–visible (UV-Vis) spectroscop…
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Determining the refractive index of human hemoglobin solutions by Kramers–Kronig relations with an improved absorption model Open
The real part of the refractive index of aqueous solutions of human hemoglobin is computed from their absorption spectra in the wavelength range 250-1100 nm using the Kramers-Kronig (KK) relations, and the corresponding uncertainty analysi…
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Single wavelength 480 Gb/s direct detection over 80km SSMF enabled by Stokes vector Kramers Kronig transceiver Open
We propose 4D modulation with directed detection employing a novel Stokes-Vector Kramers-Kronig transceiver. It shows that employing Stokes vector receiver, transmitted digital carrier and Kramers-Kronig detection offers an effective way t…
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Spectrally Efficient 168 Gb/s/λ WDM 64-QAM Single-Sideband Nyquist-Subcarrier Modulation With Kramers–Kronig Direct-Detection Receivers Open
Due to their simple and cost-effective transceiver architecture,
\nsingle-polarization and single-photodiode-based directdetection
\n(DD) systems offer advantages for metropolitan area network
\nand data-center interconnect applications. S…
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Designing refractive index fluids using the Kramers-Kronig relations Open
For a number of optical applications, it is advantageous to precisely tune the refractive index of a liquid. Here, we harness a well-established concept in optics for this purpose. The Kramers-Kronig relation provides a physical connection…
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Single-Lane 112-Gbit/s SSB-PAM4 Transmission With Dual-Drive MZM and Kramers–Kronig Detection Over 80-km SSMF Open
We have experimentally demonstrated the signal-to-signal beating interference (SSBI) mitigation capability of Kramers–Kronig (KK) detection in a single sideband (SSB) four-ary pulse-amplitude-modulation (PAM4) direct detection (DD) system.…
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110-m THz Wireless Transmission at 100 Gbit/s Using a Kramers-Kronig Schottky Barrier Diode Receiver Open
We demonstrate wireless transmission of QPSK signals at a carrier frequency of 0.3 THz using a generalized Kramers-Kronig receiver with a Schottky barrier diode. We achieve a line rate of 100 Gbit/s over a transmission distance of 110 m.
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Absolute determination of optical constants of three transition metals using reflection electron energy loss spectroscopy Open
The optical constants, n and k, of three transition metals (Cr, Co, and Pd) were determined from the measured reflection electron energy-loss spectroscopy (REELS) spectra, covering the spectral energy range from visible to vacuum ultraviol…
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Time-varying media, dispersion, and the principle of causality [Invited] Open
The article reviews general properties of time-varying dispersive materials. We first briefly discuss different dispersion models that have been proposed in the literature, the role of the causality principle, and the generalization of the…
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Fast quantitative phase imaging based on Kramers-Kronig relations in space domain Open
A fast quantitative phase imaging technology based on space-domain Kramers-Kronig relations is proposed. By incorporating Kramers-Kronig relations, we acquire distributions on phase via measurements of intensity over the captured spectrum.…
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Kramers–Kronig PAM Transceiver and Two-Sided Polarization-Multiplexed Kramers–Kronig Transceiver Open
We propose two transceiver schemes based on Kramers Kronig (KK) detection.\nOne targets low-cost high-throughput applications and uses PAM transmission in\ncombination with direct detection and digital reconstruction of the optical\nphase.…
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Predict the Phase Angle Master Curve and Study the Viscoelastic Properties of Warm Mix Crumb Rubber-Modified Asphalt Mixture Open
To identify the most accurate approach for constructing of the dynamic modulus master curves for warm mix crumb rubber modified asphalt mixtures and assess the feasibility of predicting the phase angle master curves from the dynamic modulu…
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Using The Kramers-Kronig Transforms To Retrieve The Conductivity From The Effective Complex Permittivity Open
While measuring the effective permittivity of dispersive material it may be of interest to distinguish between conductivity losses (caused by free electrons) and dielectric losses (caused by bounded electrons) which both are included in th…
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Phonon features in terahertz photoconductivity spectra due to data analysis artifact: A case study on organometallic halide perovskites Open
We propose a simple scenario where the superimposed phonon modes on the photoconductive spectra are experimental artifacts due to the invalid formula used in data analysis. By use of experimental and simulated data of CH3NH3PbI3 perovskite…
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Single-photodiode 112-Gbit/s 16-QAM transmission over 960-km SSMF enabled by Kramers-Kronig detection and sparse I/Q Volterra filter Open
We have experimentally demonstrated a single-photodiode 112-Gbit/s 16-QAM transmission over 960-km standard single mode fiber with Kramers-Kronig (KK) detection and a sparse I/Q Volterra filter (VF). KK detection is used to mitigate the si…
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Magneto-optical Kramers-Kronig analysis Open
We describe a simple magneto-optical experiment and introduce a magneto-optical Kramers-Kronig analysis (MOKKA) that together allow extracting the complex dielectric function for left- and right-handed circular polarizations in a broad ran…
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Controlled unidirectional reflection in cold atoms via the spatial Kramers-Kronig relation Open
It is known that the Kramers-Kronig (KK) relation between real and imaginary parts of the optical susceptibility in the frequency domain can also be realized in the space domain, as first proposed in [ Nat. Photonics 9 ( 7 ), 436 ( 2015 ) …
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Kramers–Kronig relation in attosecond transient absorption spectroscopy Open
The Kramers–Kronig relation (KKR) has a wide range of applications in extreme ultraviolet (XUV) and x-ray spectroscopy. However, the validity of KKR for many of these applications has not been systematically studied, while it is known to r…
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New dispersion equations for insulators and semiconductors valid throughout radio-waves to extreme ultraviolet spectral range Open
A new formulation of optical dispersion in terms of complex index of refraction, N(E) as a function of photon energy, E, applicable to insulators and semiconductors, is introduced. Previous formulations, developed over the past 200 years, …
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Kramers-Kronig relations and causality conditions for graphene in the framework of the Dirac model Open
We analyze the concept of causality for the conductivity of graphene\ndescribed by the Dirac model. It is recalled that the condition of causality\nleads to the analyticity of conductivity in the upper half-plane of complex\nfrequencies an…