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J. Meixner

Bio: J. Meixner is an academic researcher from RWTH Aachen University. The author has contributed to research in topics: Mathieu function & Non-equilibrium thermodynamics. The author has an hindex of 13, co-authored 17 publications receiving 1853 citations.

Papers
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Book ChapterDOI
01 Jan 1959
TL;DR: The Thermodynamik irreversibler Prozesse as mentioned in this paper is a makroskopische Theorie der Zustande and Zustandsanderungen in der kontinuierlich ausgebreiteten Materie.
Abstract: Die Thermodynamik irreversibler Prozesse ist eine makroskopische Theorie der Zustande und Zustandsanderungen in der kontinuierlich ausgebreiteten Materie. Sie ist eine Erweiterung der Theorie thermodyna-misch-mechanischer Gleichgewichtszustande, d. h. der klassischen Thermodynamik und kann auf hydrodynamische und aerodynamische Probleme, auf Erscheinungen der Elastizitatslehre und der Theorie der kontinuierlichen Medien in elektromagnetischen Feldern, sowie auf Vorgange in Bifluiden, d. h. in Gasplasmen, Supraleitern und Superfluiden angewandt werden. Wenn auch die Theorie dieser Erscheinungen grosenteils vor der Entwicklung der Thermodynamik irreversibler Prozesse bestand, so kann man doch sagen, das alle diese Erscheinungen methodisch und inhaltlich von der Thermodynamik irreversibler Prozesse in einheitlicher Weise umfast werden.

181 citations


Cited by
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Book ChapterDOI
01 Jan 1960

3,018 citations

Journal ArticleDOI
TL;DR: In this paper, the transmon was proposed to operate in a regime of significantly increased ratio of Josephson energy and charging energy, while maintaining sufficient anharmonicity for selective qubit control.
Abstract: Short dephasing times pose one of the main challenges in realizing a quantum computer. Different approaches have been devised to cure this problem for superconducting qubits, a prime example being the operation of such devices at optimal working points, so-called ``sweet spots.'' This latter approach led to significant improvement of ${T}_{2}$ times in Cooper pair box qubits [D. Vion et al., Science 296, 886 (2002)]. Here, we introduce a new type of superconducting qubit called the ``transmon.'' Unlike the charge qubit, the transmon is designed to operate in a regime of significantly increased ratio of Josephson energy and charging energy ${E}_{J}∕{E}_{C}$. The transmon benefits from the fact that its charge dispersion decreases exponentially with ${E}_{J}∕{E}_{C}$, while its loss in anharmonicity is described by a weak power law. As a result, we predict a drastic reduction in sensitivity to charge noise relative to the Cooper pair box and an increase in the qubit-photon coupling, while maintaining sufficient anharmonicity for selective qubit control. Our detailed analysis of the full system shows that this gain is not compromised by increased noise in other known channels.

2,807 citations

Journal ArticleDOI
TL;DR: In this paper, the authors apply the theory developed in the preceding paper to a number of questions about timelimited and bandlimited signals, and find the signals which do the best job of simultaneous time and frequency concentration.
Abstract: The theory developed in the preceding paper1 is applied to a number of questions about timelimited and bandlimited signals. In particular, if a finite-energy signal is given, the possible proportions of its energy in a finite time interval and a finite frequency band are found, as well as the signals which do the best job of simultaneous time and frequency concentration.

2,498 citations

Journal ArticleDOI
TL;DR: The successes, as well as the limits, of perturbation theory are presented, and its role in the emerging era of numerical relativity and supercomputers is discussed.
Abstract: Perturbations of stars and black holes have been one of the main topics of relativistic astrophysics for the last few decades. They are of particular importance today, because of their relevance to gravitational wave astronomy. In this review we present the theory of quasi-normal modes of compact objects from both the mathematical and astrophysical points of view. The discussion includes perturbations of black holes (Schwarzschild, Reissner-Nordstrom, Kerr and Kerr-Newman) and relativistic stars (non-rotating and slowly-rotating). The properties of the various families of quasi-normal modes are described, and numerical techniques for calculating quasi-normal modes reviewed. The successes, as well as the limits, of perturbation theory are presented, and its role in the emerging era of numerical relativity and supercomputers is discussed.

1,569 citations

ReportDOI
01 Dec 1963
TL;DR: In this article, the first order statistics of the observed electric-field strength, the observed light intensity, and observed light phase are examined, and the autocorrelation functions of the complex field and intensity processes are investigated, and that of the electric field is found to be proportional to the Fourier transform of the light intensity distribution incident on the scattering surface.
Abstract: : When laser light strikes a diffuse object, such as paper, the scattered light has been observed to possess a granular spatial structure. The statistical properties of these so-called 'sparkle patterns,' as seen by an observer in the far field of the scattering spot, are investigated. The first order statistics of the observed electric-field strength, the observed light intensity, and the observed light phase are examined. The electric field is reasoned to be a complex normal random variable; the intensity a real, exponentially distributed random variable; and the phase a uniformly distributed random variable. Higher order statistics of these random processes are also discussed. The autocorrelation functions of the complex field and the intensity processes are investigated, and that of the electric field is found to be proportional to the Fourier transform of the light-intensity distribution incident on the scattering surface. Spatial averages of the light intensity are considered and are found to converge to corresponding ensemble averages when either the area of the scattering spot or the average area grows large.

1,526 citations