Quantum tunneling composite
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This document discusses quantum tunneling and quantum tunneling composite materials. It begins with an overview of quantum tunneling and how it allows particles to pass through barriers they classically could not. It then describes quantum tunneling composite materials, which use the quantum tunneling effect to create sensors. When flexed, the materials change from insulators to conductors, allowing them to detect forces. The document discusses several potential applications of these new quantum tunneling composite sensors in areas like toys, sports, medicine, tools, robotics and keyboards.
Quantum tunneling composite
- 1. Course name : Power System Analysis Course code : 00697 Topic : Presentation on “QUANTUM TUNNELING COMPOSITE” Section : E Submitted to : Rethwan Faiz(course instructor)
- 2. Name :ID Haque,Md Rashidul : 13-24186-2 HaqueTahsin,Shamsul Arefin : 12-21353-2 Haq, Shezan Ehsanul :13-24109-2 Azmaeen,Mesbah Hossain : 13-24003-2
- 4. Consequence of the wave nature of matter First used to explain alpha decay of heavier elements in 1928 by George Gamow Shown experimentally by Leona Esaki in 1958 in the tunneling diode
- 5. At the quantum level, matter has corpuscular and wave-like properties Tunneling can only be explained by the wave nature of matter as described by quantum mechanics Classically, when a particle is incident on a barrier of greater energy than the particle, reflection occurs When described as a wave, the particle has a probability of existing within the barrier region, and even on the other side of it
- 6. An engineered material made from two or more constituents with significantly different physical or chemical properties which remain separate and distinct on a macroscopic level within the finished structure.
- 7. particles do not actually need to touch each other The nickel particles are not smooth spheres; The particles are surrounded or wetted by an insulating layer of silicone rubber which prevents them from touching even when pressure is applied. The spikes on the particles allow a higher concentration of electrons
- 8. This reduces the distance and energy needed for the electron charge
- 9. Solutions to the wave equation have the general form (I) In the barrier region, the solution becomes (II) The wave function decays exponentially in the barrier region If some portion of the wave function still exists on the other side of the barrier, transmission has occurred The width of the barrier is the most prominent factor in determining the probability of transmission (I) (II) ImagescourtesyofWikipedia
- 10. University of Colorado Tunneling Program From http://phet.colorado.edu/new/simulations/sims.ph p?sim=Quantum_Tunneling_and_Wave_Packets
- 11. George Gamow used tunneling to explain α-decay in Uranium 238 The α particle does not have enough kinetic energy to escape the nucleus There is a chance, due to it’s wave function, that it will escape the potential barrier of the nucleus boundary Due to the exponential decay nature of the wave function in the barrier region, the width of the barrier can manifest itself in the half-life of the isotope 92 238 U→90 234 Th+2 4 He
- 12. As microchip developers create smaller production processes, we reach the limit of classical computer technology The feature size of the most advanced microchip today is 45 nm With such small widths, the electrons in the channel can tunnel out with relative ease, possibly affecting other transistors in the chip Current approximations show that the minimum feature size is about 4 nm After that point tunneling is not only possible, but highly likely and the chip would fail
- 13. The Scanning Tunneling Microscope was invented in 1981 by Gerd Binnig and Heinrich Rohrer When a metal tip, usually made of tungsten or platinum-iridium, is brought within .4-.7nm of the sample, electrons tunnel across the gap and create a current in the tip This current is then fed to a computer and used to generate an image of the atomic surface of the sample Image courtesy of Wikipedia
- 14. At this distance the coulomb force between the tip and an atom of the sample is actually enough to move the atom This has allowed physicists to create images and structures on the atomic level Images courtesy of IBM
- 15. Developed in 1958 by Leona Esaki at Sony Tunneling diodes are designed with a heavily doped p-n junction that is only 10 nm wide At low voltages, the p and n states are aligned, allowing electrons to tunnel across the gap As voltage increases these states become more misaligned and fewer electrons flow This negative resistance region allows the diode to operate at very high frequencies, well into the Gigahertz range Image courtesy of Wikipedia
- 16. A UK company is developing flexible force sensors that use quantum tunneling These sensors are made out of Quantum Tunneling Composite materials QTC’s are essential non-conducting in their normal state When flexed by an applied force, the atoms of the QTC are brought close enough so that tunneling can occur Tunneling changes the QTC from an insulator to a conductor with a predictable exponential decay in resistance Image courtesy of Peratech
- 17. Toys and Games QTC may be used to replace existing switches and sensors in games controllers and computer mice to give increased sensitivity for greater control.
- 18. QTC in Sport can be used as a sensor in many areas, from force sensors in training dummies for boxing to fencing jackets which incorporate touch sensors.
- 19. QTC in Medicine sensors can be incorporated into the cuffs of blood pressure machines to ensure that they are tightened correctly to reduce inaccurate readings.
- 20. QTC in Clothing Wearable applications include mp3 player controllers built into the sleeves of jackets.
- 21. QTC in Tools incorporated into the handles of power tools to act as a cut out switch or variable controller.
- 22. QTC in Robotics used as durable finger pads in prosthetic / robotic hands which allow the amount of pressure being applied to be controlled.
- 23. QTC in Keyboards used to make a flexible, durable, portable QWERTY keyboard which can be connected to a mobile phone, laptop or other device using Bluetooth.
- 24. http://www.peratech.co.uk/science.htm http://en.wikipedia.org/wiki/Tunnel_diode http://en.wikipedia.org/wiki/Quantum_tunneling http://en.wikipedia.org/wiki/Scanning_tunneling_microscope http://psi.phys.wits.ac.za/teaching/Connell/phys284/2005/lectur e-02/lecture_02/node13.html Rex, A. & Thornton, S. T. (2006) Modern Physics for Scientists and Engineers 3rd ed. Belmont CA: Thomson Brooks/Cole http://www.almaden.ibm.com/vis/stm/gallery.html