Factbites
 Where results make sense
About us   |   Why use us?   |   Reviews   |   PR   |   Contact us  

Topic: Magnetic flux quantum


Related Topics

In the News (Mon 17 Jun 19)

  
  Magnetic flux quantum - Wikipedia, the free encyclopedia
The quantum of magnetic flux is a physical constant, as it is independent of the underlying material as long as it is a superconductor.
If the area under consideration consists entirely of superconducting material, the magnetic flux through it will be zero, for supercurrents always flow in such a way as to expel magnetic fields from the interior of a superconductor, a phenomenon known as the Meissner effect.
A non-zero magnetic flux may be obtained by embedding a ring of superconducting material in a normal (non-superconducting) medium.
en.wikipedia.org /wiki/Magnetic_flux_quantum   (406 words)

  
 Quantum - Wikipedia, the free encyclopedia
For instance, a "light quantum", being a unit of light (that is, a photon).
Usually referred to as quantum "mechanics", it is regarded by virtually every professional physicist as the most fundamental framework we have for understanding and describing nature, for the very practical reason that it works.
Quantum theory, the branch of physics based on quantization, began in 1900 when Max Planck published his theory explaining the emission spectrum of fl bodies.
en.wikipedia.org /wiki/Quantum   (1363 words)

  
 Magnetic flux - LearnThis.Info Enclyclopedia   (Site not responding. Last check: 2007-10-21)
Magnetic flux, usually denoted by Greek letter Φ, is a measure of quantity of magnetism, taking account of the strength and the extent of a magnetic field.
The SI unit of magnetic flux is the weber.
The direction or vector of the magnetic flux is by defenition from the south to the north pole of a magnet (within the magnet).
encyclopedia.learnthis.info /m/ma/magnetic_flux.html   (232 words)

  
 Magnetic flux quantum -- Facts, Info, and Encyclopedia article   (Site not responding. Last check: 2007-10-21)
The quantum of magnetic flux is a (Click link for more info and facts about physical constant) physical constant, as it is independent of the underlying material as long as it is a superconductor.
The magnetic flux quantum may be measured with great precision by exploiting the (Click link for more info and facts about Josephson effect) Josephson effect.
This is remarkable since h is generally associated with the behavior of microscopically small systems, whereas the quantization of magnetic flux in a superconductor and the quantum Hall effect are both collective phenomena associated with (Click link for more info and facts about thermodynamically) thermodynamically large numbers of particles.
www.absoluteastronomy.com /encyclopedia/m/ma/magnetic_flux_quantum.htm   (435 words)

  
 Apparatus for positioning a pick-up coil for detecting magnetic flux quantum trapped in a superconductor - Patent ...
Since the relative position of the head in the direction along the surface of the superconductor is changable by drive means for moving the superconductor or the head, the distribution of the magnetic flux which is trapped in the superconductor is measured by scanning the surface of the superconductor with pick-up coil.
Magnetic flux trapped in a superconductor 11 is sensed by a pick-up coil 8 and detected by SQUID 10 through an input coil 9.
8 shows a relation of the amount of the magnetic flux sensed by the pick-up coil 8 to the lifted height (gap space) between the coil and the surface of the superconductor wherein the magnetic flux source is assumed as a single magnetic flux quantum trapped in the superconductor 11.
www.freepatentsonline.com /5053707.html   (2271 words)

  
 Measuring Magnetic Field Strength using Quantum Magnetometers
GEM's quantum magnetometer technical paper describes the types of quantum magnetometers, their operating principles, and some of the guidelines for using these geophysical instrumentation systems in real-world surveying environments.
Protons in this field are polarized to a stronger net magnetization corresponding to the thermal equilibrium of stronger magnetic flux density.
When the auxiliary flux is released, the "polarized" protons precess to re-align themselves with the "normal" magnetic flux density.
www.gemsys.ca /Magnetometers/16_about_magnetometers.htm   (693 words)

  
 Digital magnetic flux measuring apparatus using superconducting quantum interference device with flux trapping ...
A fluxmeter using a superconducting quantum interference element according to claim 7, wherein the full range of the feedback circuit is made variable and is varied in order to set the feedback current at a time when the trapped magnetic flux is detected and measured.
The positive external magnetic flux (.PHI..sub.e.sup.+) that is applied to the pickup coil 51b under this condition, is transferred to the SQUID ring 51a via the flux transformer 51c, whereby the Ic-axis undergoes parallel translation toward the right side from the relationship of FIG.
As a matter of fact, however, since the magnetic flux trapped by the SQUID ring is compensated, the counter generates the corresponding offset quantity and thereby the counting range or the dynamic range of the counter is narrowed.
www.freepatentsonline.com /5287058.html   (5709 words)

  
 I 4 1 Magnetic Flux   (Site not responding. Last check: 2007-10-21)
Magnetic flux is proposed to be the flow of background pure matter particles.
There is a correlation between the left hand angular momentum of the electrons and the left hand flow of magnetic flux caused by their motion.
The direction of the magnetic field around the wire is indicated by the diamonds with the north and south magnetic poles labeled.
www.starlight-pub.com /Matter/PartI/I4/I42Magnetic.html   (618 words)

  
 Flux   (Site not responding. Last check: 2007-10-21)
In biology, flux refers to the movement of molecules across a membrane: the rate of diffusion of a substance across a permeable membrane.
Net flux is directly proportional to the concentration difference across the membrane, the surface area of the membrane, and the membrane permeability constant.
For electromagnetic radiation, the flux of the Poynting vector through a surface is the power, or energy per unit time, passing through that surface.
www.worldhistory.com /wiki/F/Flux.htm   (763 words)

  
 Quantum computing method using magnetic flux states at a josephson junction - US Patent 6563311   (Site not responding. Last check: 2007-10-21)
Quantum computing generally involves initializing the states of N qubits (quantum bits), creating controlled entanglements among the N qubits, allowing the quantum states of the qubits to evolve under the influence of the entanglements, and reading the qubits after they have evolved.
One embodiment of the invention is a quantum computing structure such as a quantum coherer or a quantum register that includes a bank of a superconducting material and an island of a superconducting material, wherein at least one of the island and the bank is a d-wave superconductor.
In accordance with another aspect of the invention, determining the measured magnetic moment includes: grounding the island to fix the supercurrent in the first or second state; and measuring the magnetic flux produced by the supercurrent while the island is grounded.
www.patentstorm.us /patents/6563311.html   (12011 words)

  
 Magnetic Recording Measurements 2002
Magnetic imaging techniques and measurements are developed for the authentication of recorded information and the recovery of data from samples of damaged magnetic recording media.
The magnetic properties of the samples have been measured in a B-H looper and a SQUID magnetometer to verify that the superconducting loop is continuous and functional.
The inverse spin-reorientation transition from the canted state to the uniform, in-plane magnetic structure with thickness was demonstrated for a thin film supported on a nonmagnetic substrate.
www.boulder.nist.gov /div818/81803/2002/MagneticRecordingMeasurements   (1579 words)

  
 IBM Research | Projects | PAIRING SYMMETRY IN CUPRATE SUPERCONDUCTORS!
The magnetic fields in these samples were imaged with a scanning Superconducting Quantum Interference Device (SQUID) microscope.
The half-flux quantum effect occurs for all of the high-Tc superconductors that have sufficiently high supercurrents across the grain boundaries.
These are SQUID microscope images of the half-magnetic flux quantum in a tricrystal sample of YBCO at selected temperatures.
www.research.ibm.com /halfvortex   (759 words)

  
 Quantum Dots   (Site not responding. Last check: 2007-10-21)
A short introduction to quantum dots and an overview of the research in the group of Leo Kouwenhoven.
It is especially interesting to observe the effect of a magnetic fieldd, B, on the atom-like properties.
A magnetic flux-quantum in an atom requires typically a B-field as high as 10^6 T, whereas for dots this is of the order 1 T, which is experimentally accessible.
vortex.tn.tudelft.nl /grkouwen/qdotsite.html   (618 words)

  
 [No title]   (Site not responding. Last check: 2007-10-21)
The observation of the magnetic flux quantum, $\Phi_0=hc/2e$, appeared at its time as direct evidence that superconducting current is carried by electrons involved in Cooper pairs.
Until recently it was widely held that an external magnetic field penetrates a second-kind superconductor as an ensemble of individual vortices, each carrying exactly one magnetic flux quantum.
The authors believe it is the magnetic flux changes occurring in vortices that are behind the superconducting film results yet unexplained.
ufn.ioc.ac.ru /news/eng/2000/1000.html   (1553 words)

  
 Read about Magnetic flux quantum at WorldVillage Encyclopedia. Research Magnetic flux quantum and learn about Magnetic ...   (Site not responding. Last check: 2007-10-21)
The magnetic flux quantum may be measured with great precision by exploiting the
This is remarkable since h is generally associated with the behavior of microscopically small systems, whereas the quantization of magnetic flux in a superconductor and the quantum Hall effect are both
The quantization of magnetic flux is closely related to the
encyclopedia.worldvillage.com /s/b/Josephson_constant   (396 words)

  
 Research Introduction
The magnetic field penetrates into the superconductors in the form of quantum magnetic flux lines or vortices.
The static and dynamic behavior of vortex matter determines the electrical and magnetic properties of the superconductors, comprehension of which is essential for technological applications.
We have used this technique, as well as additional transport methods, to study a number of unique phenomena in HTS andconventional superconductors such as the first-order melting, disorder-driven transitions, decoupling and sublimation of the vortex pancakes, metastability and memory effects, distribution of the transport current, surface and geometrical barriers, effects of disorder, and shear-induced decoupling.
www.weizmann.ac.il /home/fnsup/research-introduction.html   (445 words)

  
 ANTI-MEISSNER EFFECT.   (Site not responding. Last check: 2007-10-21)
Chill a superconductor in the presence of a magnetic field.
This is an example of a paramagnetic (magnetic enhancement) Meissner effect, in contrast to the diamagnetic (magnetically neutralizing) Meissner effect customarily observed in superconductors.
Geim's experiment, using micron-sized disks, is the first to measure this effect with a precision of better than one magnetic flux quantum.
newton.ex.ac.uk /aip/glimpse.txt/physnews.404.2.html   (178 words)

  
 Prof. Ustinov Group Homepage
Magnetic flux quanta penetrating the junction along the tunnel barrier are called Josephson vortices.
The annular Josephson junction can be prepared in a state in which a single magnetic flux quantum is topologically trapped between the two superconducting electrodes threading only one of them.
A magnetic flux quantum trapped in the junction has the character of a solitary wave which propagates along the junction when a bias current is applied.
fluxon.physik.uni-erlangen.de /pages/research/qc_elements/qc_01intro.html   (269 words)

  
 Quantum Dots
Quantum dots are small devices that contain a tiny droplet of free electrons.
Unlike atoms however, quantum dots can be easily connected to electrodes and are therefore excellent tools to study atomic-like properties.
By measuring electron transport through quantum dots, a periodic table of artificial 2D elements can be obtained.
qt.tn.tudelft.nl /grkouwen/qdotsite.html   (618 words)

  
 Nonlocal electrodynamics of superconductors applied to vortex lattices Vladimir G. Kogan, Ames Laboratory   (Site not responding. Last check: 2007-10-21)
All applications of superconductors are related to their behavior in magnetic fields, which is quite unusual and different from that of normal metals.
The field penetrates most of superconductors in the form of tiny flux filaments surrounded by circulating currents (vortices) and containing a certain amount of magnetic flux, “flux quantum”.
The nonlocal London theory is now a major theoretical tool in describing low temperature reversible magnetic behavior of a large class of superconductors (having high Ginzburg-Landau parameter) on a submicron scale (vortex lattices) as well as the macroscopic scale (magnetization) [3].
cmp.ameslab.gov /highlights/kogan.html   (392 words)

  
 Research on Superconducting Quantum Devices
The digital logic of RSFQ is based upon the storage and transportation of a single magnetic flux quantum.
The ultimate sensitivity of Superconducting Quantum Interference Devices is being used to visualize the spatial distribution of the magnetic flux.
We were the first to develop a variable temperature high-resolution SQUID microscope (picture), which allows for measurements in the range 5-100 K. It is used to study on a local level the magnetic phase transitions, vortex state of superconductors, performance of electronic circuits, including RSFQ, and other magnetism related phenomena.
fy.chalmers.se /assp/quox/sqd.html   (708 words)

  
 The world's top Quantum Mechanics websites   (Site not responding. Last check: 2007-10-21)
We give a selfcontained introduction to the theory of quantum groups according to Drinfeld highlighting the formal aspects as well as the applications to the Yang-Baxter equation and representation theory.
The audience is mainly first-year graduate students, and it is assumed that the reader has a good foundation in quantum mechanics.
Article which teaches the basics of quantum mechanics with help of digital videos showing the time evolution of wave packets in various potentials, with interference, tunneling.
dirs.org /dir-wiki.cfm/Top/Science/Physics/Quantum_Mechanics   (728 words)

  
 Spontaneous Magnetic Flux and Quantum Noise in an Annular Mesoscopic SND Junction   (Site not responding. Last check: 2007-10-21)
Spontaneous Magnetic Flux and Quantum Noise in an Annular Mesoscopic SND Junction
We consider spontaneous magnetic flux in an annular s-wave/normal metal/d-wave superconductor (SND) Josephson junction.
The flux magnitude is not quantized and is determined by the parameters of the system.
flux.aps.org /meetings/YR98/BAPSMAR98/abs/S3530006.html   (101 words)

  
 A SCANNING MAGNETIC FLUX MICROSCOPE,   (Site not responding. Last check: 2007-10-21)
A SCANNING MAGNETIC FLUX MICROSCOPE, a device that can map magnetic fields with a spatial resolution of about 80 microns and a field sensitivity of 7 pico-Tesla-Hz**-1/2, has been developed by a Maryland-Berkeley collaboration (contact Frederick Wellstood, 301-405-7649).
The detector uses a 77-K superconducting quantum interference device to sense tiny magnetic fields from a sample which moves back and forth beneath the SQUID in 1-micron steps.
The scientific uses of the magnetic microscope include prospecting for the characteristic fields emanating from microscopic nuggets of superconductor buried inside otherwise non-superconducting samples.
newton.ex.ac.uk /aip/glimpse.txt/physnews.165.2.html   (180 words)

  
 Quantum - Encyclopedia.WorldSearch   (Site not responding. Last check: 2007-10-21)
A quantum is the smallest increment into which many physical properties are subdivided.
The word quantum comes from the Latin word for "how much?".
Mathematica for Theoretical Physics: Electrodynamics, Quantum Mechanics, General Relativity, and Fractals
encyclopedia.worldsearch.com /quantum.htm   (96 words)

  
 [No title]
Calibration and compensation techniques, nonmagnetic materials and electronic components, and techniques for compensating and negating the effects of stray magnetic fields generated by nearby materials and electronic components.
Fiber optic magnetic sensors with compensated temperature and pressure variations Detection methods for use with fiber optic interferometric and polarimetric magnetic field sensors with compatible, high sensitivity detection methods that permit discrimination against environmental and instrumental noise at frequencies below 10hz.
Gravity meter and gravity gradiometer technology(Better than 100 microgals(.1 milligal)) Supercondicting gravity gradiometers Modeling and analysis of objects Characterization of object cross section as a function of size, frequency, shape, scatter matrix, and polarization properties.
www.rhfweb.com /aether.html   (508 words)

Try your search on: Qwika (all wikis)

Factbites
  About us   |   Why use us?   |   Reviews   |   Press   |   Contact us  
Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.