Search results for " Joseph"

Microwave nanobolometer based on proximity Josephson junctions

2014

We introduce a microwave bolometer aimed at high-quantum-efficiency detection of wave packet energy within the framework of circuit quantum electrodynamics, the ultimate goal being single microwave photon detection. We measure the differential thermal conductance between the detector and its heat bath, obtaining values as low as $5\phantom{\rule{4.pt}{0ex}}\text{fW}/\mathrm{K}$ at $50\phantom{\rule{4.pt}{0ex}}\text{mK}$. This is one tenth of the thermal conductance quantum and corresponds to a theoretical lower bound on noise-equivalent power of order ${10}^{\ensuremath{-}20}\phantom{\rule{4.pt}{0ex}}\text{W}/\sqrt{\text{Hz}}$ at $50\phantom{\rule{4.pt}{0ex}}\text{mK}$. By measuring the dif…

Fluxons in Josephson Transmission Lines

1996

The superconducting Josephson junctions (Barone and Paterno 1982; Parmentier 1978; Lomdahl 1985; Likharev 1986; Pedersen 1986) have proven to be one of the most successful testing grounds for nonlinear wave theory; their use for information processing and storage is quite attractive. In the long Josephson junction or transmission line, the physical quantity of interest is a quantum of magnetic flux, or a fluxon, which has a soliton behavior. It is a remarkably robust and stable object, which can be easily manipulated at high speed and stored electronically. Consequently it should be used as a basic bit in information processing systems.

Josephson junctions and SQUIDs based on artificial grain boundaries in Bi 2 Sr 2 Ca 2 Cu 3 O 10 -thin films

1996

ABSTRACT High quality thin films of Bi2 Sr Ca2 Cu3 0 with critical temperatures of 95 K were used to prepare grainboundary josephson junctions on commercial 36.8° SrTiOg-bicrystal substrates. IR-products of 50 pV at 77 Kand 0.7 mV at 4.2 K have been reached. For temperatures higher than 50 K the current-voltage curves of thejunctions can be well described by the resistively shunted junction (RSJ) model and show no hysteresis. Fromthe hysteretic behavior at low temperature we estimate a junction capacitance of 2ljiF/cm2. The Fraunhoferpattern of the critical current in an external applied field shows, that the junctions are inhomogeneous on a pm scale. The SQUID modulation of a 30 x 40 pm2 w…

“Podalirius” o “Polidarius”? Da Arrigo da Settimello a Guido delle Colonne

2016

This paper is dedicated to the defence of the variant "Polidarius" (and not the correction in the vulgate "Podalirius") that occurs in all the manuscripts of Henry of Septimello's «Elegia» (book IV, line 209). "Polidarius", however, has many attestations in Medieval Troy literary tradition (Joseph of Exeter, Benoît de Sainte-Maure, Guido delle Colonne) and is an alternative, correct and good name for the famous mythical doctor, son of Asclepius and brother of Machaon.

Nonlinear relaxation in quantum and mesoscopic systems

2013

The nonlinear relaxation of three mesoscopic and quantum systems are investigated. Specifically we study the nonlinear relaxation in: (i) a long Josephson junction (LJJ) driven by a non-Gaussian Lévy noise current; (ii) a metastable quantum open system driven by an external periodical driving; and (iii) the electron spin relaxation process in n-type GaAs crystals driven by a fluctuating electric field. In the first system the LJJ phase evolution is described by the perturbed sine-Gordon equation. Two well known noise induced effects are found: the noise enhanced stability and resonant activation phenomena. We investigate the mean escape time as a function of the bias current frequency, nois…

Hitler A Bayreuth. Storia di un'amicizia (1923-1940)

2013

Il saggio si sofferma sulle vite parallele di Winifred Majorie Williams (moglie di Sigfried Wagner e dopo la sua morte "Signora di Bayreuth") e Adolf Hitler, grande ammiratore dell'opera wagneriana e "amico" di famiglia della famiglia Wagner a partire dalla fine degli anni Venti. Il testo ripercorre le tappe del rapporto personale fra Winifred Wagner e Adolf Hitler, rievocando al tempo stesso alcuni episodi della biografia hitleriana legati al Festival di Bayreuth.

Developement of new techniques of Optimal Control in Quantum Dynamics : from nuclear magnetic resonance to molecular physics

2011

The goal of this thesis is to apply the optimal control theory to the dynamics of quantum systems.The first part aim at introducing the tools of optimal control in quantum control which were initially developedin mathematics. This approch has been applied on different kinds of quantum system with small and largedimensions. The first part of this manuscript introduces the optimal control tools which are used with a pointof view suited to a public of physicists. In the second part these techniques are used to control the dynamics ofspins in NMR and MRI. The third part deals with the development of new iterative algorithms applied to thecontrol by laser fields of the rotational dynamics of lin…

Re-Enchantment and Contemporary Demonology

2017

Generation of travelling sine-Gordon breathers in noisy long Josephson junctions

2022

The generation of travelling sine-Gordon breathers is achieved through the nonlinear supratransmission effect in a magnetically driven long Josephson junction, in the presence of losses, a current bias, and a thermal noise source. We demonstrate how to exclusively induce breather modes by means of controlled magnetic pulses. A nonmonotonic behavior of the breather-only generation probability is observed as a function of the noise intensity. An experimental protocol providing evidence of the Josephson breather's existence is proposed.

Ac-locking of thermally-induced sine-Gordon breathers

2023

A complete framework for exciting and detecting thermally-induced, stabilized sine-Gordon breathers in ac-driven long Josephson junctions is developed. The formation of long-time stable breathers locked to the ac source occurs for a sufficiently high temperature. The latter emerges as a powerful control parameter, allowing for the remarkably stable localized modes to appear. Nonmonotonic behaviors of both the breather generation probability and the energy spatial correlations versus the thermal noise strength are found. The junction's resistive switching characteristics provides a clear experimental signature of the breather.