Search results for "Coherence"
showing 10 items of 905 documents
Femtosecond polarization spectroscopy in molecular gas mixtures: Macroscopic interference and concentration measurements
2000
0021-9606; Raman-induced polarization spectroscopy (RIPS) experiments combined with homodyne detection have been conducted with a femtosecond laser at room temperature and low pressure (p < 2 atm) in CO2-N2 mixtures as well as in air (O2-N2 mixtures). Each molecule of the mixture produces its own time-dependent signal, measured as a series of recurring transients. Macroscopic interference is observed when transients of both molecules overlap in the time domain. This interference leads to a large modification of the signal, which is well reproduced by calculations. The total signal recorded in CO2-N2 or O2-N2 mixtures of known concentration is analyzed in order to measure the polarizability …
The Polyphonic Theology of the Church Fathers
2014
Prof. Dr. Dres. H. c. Christoph Marschies (Humboldt University Berlin, Germany) in collaboration with Prof. Dr. Michael Welker (Heidelberg University, Germany) initiated an international project to which about 25 international scholars of high profile were invited to participate. The purpose of the project is to gain a new and nuanced perspective on the theology of 19 church fathers: Justin the Martyr, Irenaeus of Lyon, Tertullian, Origen, Cyprian, Eusebius, Athanasius of Alexandria, Basil the Great, Gregory of Nazianzus, Gregory of Nyssa, John Chrysostom, Augustine, Cyril of Alexandria, Leo the Great, Theodoret of Cyrus, Boethius, Isidore, Maximus the Confessor and John Damascene. Research…
Exploring coherence and authorship in pedagogical link-making in science
2021
Despite rapid changes in education, science classrooms will remain central forums where fragmented pieces of information are brought together to construct coherent knowledge as concepts and explana...
Introduction: The World as a Stereogram
2014
This paper presents the historically most important theories of how visual perception is made spatial in the cognitive processing of the sensory input to the eye. All of them involve active engagement of the mind. Firstly, in the medieval theories physiological processes developed three-dimensional imagery in the brain, and active mental processing was needed to build coherence in the perceptual experience as a whole but not to yield the basic idea of spatiality. Secondly, according to Descartes, the eyes produced a unified two-dimensional visual image that was neurally transmitted to the inner surface of the brain. The innate conception of three-dimensional spatiality was superimposed inte…
A nonlinear electronic circuit mimicking the neuronal activity in presence of noise
2013
We propose a nonlinear electronic circuit simulating the neuronal activity in a noisy environment. This electronic circuit is ruled by the set of Bonhaeffer-Van der Pol equations and is excited with a white gaussian noise, that is without external deterministic stimuli. Under these conditions, our circuits reveals the Coherence Resonance signature, that is an optimum of regularity in the system response for a given noise intensity.
Optical d-level frequency-time-based cluster states
2019
Cluster states, a specific class of multi-partite entangled states, are of particular importance for quantum science, as such systems are equivalent to the realization of one-way (or measurement-based) quantum computers [1]. In this scheme, algorithms are implemented through high-fidelity measurements on the parties of the state [2]. While two-level (i.e. qubit) cluster states have been realized so far, increasing the number of particles to boost the computational resource comes at the price of significantly reduced coherence time and detection rates, as well as increased sensitivity to noise, restricting the realization of discrete cluster states to a record of eight qubits. In contrast, t…
Magnetometry with Nitrogen-Vacancy Centers in Diamond
2016
This chapter covers magnetic sensing with nitrogen-vacancy (NV) defect centers in diamond. The NV center fundamentals are introduced and NV optically detected magnetic resonance techniques for dc and ac magnetic sensing are summarized. After reviewing some successful sensing applications, the advantages for using NV magnetometry, as well as some ongoing challenges, are enumerated.
Spatial information transmission using orthogonal mutual coherence coding.
2005
We use the coherence of a light beam to encode spatial information. We apply this principle to obtain spatial superresolution in a limited aperture system. The method is based on shaping the mutual intensity function of the illumination beam in a set of orthogonal distributions, each one carrying the information for a different frequency bandpass or spatial region of the input object. The coherence coding is analogous to time multiplexing but with multiplexing time slots that are given by the coherence time of the illumination beam. Most images are static during times much longer than this coherence time, and thus the increase of resolution in our system is obtained without any noticeable c…
Ultrafast dynamics of halogens in rare gas solids
2007
We perform time resolved pump-probe spectroscopy on small halogen molecules ClF, Cl2, Br2, and I2 embedded in rare gas solids (RGS). We find that dissociation, angular depolarization, and the decoherence of the molecule is strongly influenced by the cage structure. The well ordered crystalline environment facilitates the modelling of the experimental angular distribution of the molecular axis after the collision with the rare gas cage. The observation of many subsequent vibrational wave packet oscillations allows the construction of anharmonic potentials and indicate a long vibrational coherence time. We control the vibrational wave packet revivals, thereby gaining information about the vib…
Iterated Conditionals and Characterization of P-Entailment
2021
In this paper we deepen, in the setting of coherence, some results obtained in recent papers on the notion of p-entailment of Adams and its relationship with conjoined and iterated conditionals. We recall that conjoined and iterated conditionals are suitably defined in the framework of conditional random quantities. Given a family \(\mathcal {F}\) of n conditional events \(\{E_{1}|H_{1},\ldots , E_{n}|H_{n}\}\) we denote by \(\mathcal {C}(\mathcal {F})=(E_{1}|H_{1})\wedge \cdots \wedge (E_{n}|H_{n})\) the conjunction of the conditional events in \(\mathcal F\). We introduce the iterated conditional \(\mathcal {C}(\mathcal {F}_{2})|\mathcal {C}(\mathcal {F}_{1})\), where \(\mathcal {F}_{1}\)…