Spintronics

• 1. SpintronicsSAMEER PATEL|AAKASH MASAND

2. Why Spintronics? Moores Law:No. of Transistor doublesin every 18 months. Complexity:Complex Chip Design &Power Loss. 3. Introduction To Spintronics Conventional electronic devices rely on the transport of electrical chargecarriers electrons in a semiconductor such as silicon.Now, however, physicists are trying to exploit the spin of the electronrather than its charge to create a remarkable new generation ofspintronic devices which will be smaller, more versatile and more robustthan those currently making up silicon chips and circuit elements. Thepotential market is worth hundreds of billions of dollars a year. 4. The Spin The spin is represented by avector. For an electron spinningwest to east, the vector pointsnorth or up and it pointsdown for the opposite spin. In an ordinary electronic circuit,the spins are oriented at randomand have no effect on the currentflow. Spintronic devices create spin-polarized currents and use the spinto control the current flow. 5. The Giant Magneto Resistance A Nano scale phenomena. Giant refers to giant change inresistance due to current. It is a quantum mechanical magnetoresistance effect observed in thin-filmstructures composed of alternatingferromagnetic and non-magnetic layers.The Hard Drive 6. The Structure and Working of GMR A Giant Magnetoresistive device ismade of at least two ferromagneticlayers separated by a spacer layer. When the magnetization of the twooutside layers is aligned, the resistanceis at its lowest. Conversely when magnetizationvectors are antiparallel, a highresistance is developed. Small fields can produce big effects. Parallel and perpendicular currentsare developed depending on thespin. 7. Magneto Resistive RAM An important spintronicdevice, which is supposed to beone of the first spintronic devicesthat have been invented, isMRAM. Unlike conventional random-access, MRAMs do not losestored information once thepower is turned off. 8. Quantum Computing A quantum computer is a machine thatperforms calculations based on the laws ofquantum mechanics, which is thebehavior of particles at the sub-atomiclevel. A bit of data is represented by a singleatom that is in one of two states denotedby |0> and |1>. A single bit of this form isknown as a qubit. A physical implementation of a qubitcould use the two energy levels of anatom. An excited state representing |1>and a ground state representing |0>. 9. Advantages of Spintronics Low power consumption. Less heat dissipation. Takes up lesser space on chip, thus more compact. Spin manipulation is faster. Spintronics does not require unique and specialized semiconductors.Common metals such as Fe, Al, etc. can be used. 10. Questions?