Single electron transistor

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single elctron transistors are the future of quantum computing

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  • 1. In 19th century Shockley, Brattain, Bardeen In 19th century Shockley, Brattain, Bardeen invented the information age the transistor. invented the information age the transistor.Moores law states that transistor density on Moores law states that transistor density on integrated circuit doubles at every two years. integrated circuit doubles at every two years.

2. A single-electron transistor consists of a small conducting island connected to an source and drain leads by tunnel junctions and connected to one or more gates. Source and drain electrodes are attached to the island via a tunnel barrier. operation relies on single electron tunneling through a Nano scale junction. many electrons (1000-10, 000 electrons) simultaneously participate from the source to the drain current in the conventional MOSFETs, electrons in SET devices are transferred one-by-one through the channel. 3. Ec IF ENERGY IS NOT AVAILABLE TRANSPORT IS BLOCKED 4. Requirement on resistance t=RC typical time to charge/discharge of an island E t=(e^2/C)RC> h/(2) Heisenberg uncertainty principleTo observe SET effects this condition must be fulfilledh RQ > 2 e kT 1 C < e eE C>>kT 5. CONSTANT INTERACTION MODEL Electrostatics gives the following relation between the different potentials and the charge Q on the island (VD =0)CVi-CggVgg=Q CVi-C V =QWhere the total charge isThis equation can be written in the form with i.e., the potential on the dot is determined by the charge residing on it and by the induced potential V ext of the source, drain and gate.V = C V /C V = C V /C ext extgg gg 6. Sketch of the electrostatic potential energy experienced by an electron moving at the interface between GaAs and AlGaAsSpaceenergy diagrams of a singleelectron transistor in which electrons are confined between two tunneling barriers. The plunger gate voltage is increased from (a) to (c). 7. With reference to previous slideSchematic drawing of aaSET. Wires are connected to source and drain contacts to pass current Schematic drawing of SET. Wires are connected to source and drain contacts to pass current through the 2DEG at the GaAs/AlGaAs interface. Wires are also connected to the confining through the 2DEG at the GaAs/AlGaAs interface. Wires are also connected to the confining electrodes to bias them negatively and to the gate electrode that controls the electrostatic electrodes to bias them negatively and to the gate electrode that controls the electrostatic energy of the confined electrons. energy of the confined electrons. 8. Conductance of a SET as a function of the gate voltage. The spacing between the peaks is the voltage necessary to add one electron to the artificial atom. 9. Initial device structure of SETSIMOX wafer. A type of SOI.Conductance oscillations as a function of the gate voltage measured at 300 K at a drain voltage of 10 mV. 10. Initial structure of the twin SETs before V-PADOXConductance oscillations as a function of the gate voltage measured at 40 K and at a drain voltage of 10 mV. 11. Supersensitive electrometry:-If the source-drain voltage to a singleelectron transistor is slightly above its Coulomb blockade threshold, source-drain current through the device is extremely sensitive to the gate voltage.Microwave detection:-The videoresponse ("photoresponse") of singleelectron systems to electromagnetic radiation with frequency f=Ec/h. Microwave has low frequency, and so low energy, so detection would not have been possible without SET. 12. OTHERGRID SYSTEMSINGLE ELECTRON MOS MEMORYTEMPERATURE STANDARDSNOVORAMSCALING OF FLASH MEMORY DEVICES 13. SET+CMOS+SETMOS SET+CMOS+SETMOS SETs and CMOS SETs and CMOS transistors in SETMOS transistors in SETMOS devices can provide devices can provide enough gain and current enough gain and current drive to perform logic drive to perform logic functions on aa much functions on much smaller scale than smaller scale than possible with just an possible with just an CMOS. CMOS.More uses of electrometers More uses of electrometers Electrometers based on SET transistors could also be used to measure the quantum superposition of charge states in a island connected by a tunnel junction to a superconductor. 14. M. A. Kastner, The single electron transistor and artificial atoms, Ann. Phy. M. A. Kastner, The single electron transistor and artificial atoms, Ann. Phy. (Leipzig), vol. 9, pp. 885-895, 2000. (Leipzig), vol. 9, pp. 885-895, 2000. http://www.princeton.edu/~chouweb/newproject/research/SEM/Intro.html http://www.princeton.edu/~chouweb/newproject/research/SEM/Intro.html http://sergeyfrolov.wordpress.com/teaching/ http://sergeyfrolov.wordpress.com/teaching/ Solid State Electronic Devices(sixth edition) Ben G. Streetman, Sanjay Kumar Solid State Electronic Devices(sixth edition) Ben G. Streetman, Sanjay Kumar Banerjee Banerjee Electronics fundamental and applications(11th edition) D. Chattopadhyay, P.C. Rakshit Electronics fundamental and applications(11th edition) D. Chattopadhyay, P.C. Rakshit http://source.theengineer.co.uk/ http://source.theengineer.co.uk/ http://www.engineering.usu.edu/classes/ece/6430/fabrication1.pdf http://www.engineering.usu.edu/classes/ece/6430/fabrication1.pdf http://luciano.stanford.edu/~shimbo/set.html http://luciano.stanford.edu/~shimbo/set.html http://www.physicsandastronomy.pitt.edu/content/jeremy-levy http://www.physicsandastronomy.pitt.edu/content/jeremy-levy Sketched oxide single-electron transistor", Guanglei Cheng, Pablo F. Siles, Feng Bi, Sketched oxide single-electron transistor", Guanglei Cheng, Pablo F. Siles, Feng Bi, Cheng Cen,Daniela F. Bogorin, Chung Wung Bark, Chad M. Folkman, Jae-Wan Park, Cheng Cen,Daniela F. Bogorin, Chung Wung Bark, Chad M. Folkman, Jae-Wan Park, Chang-Beom Eom, Gilberto Medeiros-Ribeiro and Jeremy Levy, Nature Chang-Beom Eom, Gilberto Medeiros-Ribeiro and Jeremy Levy, Nature Nanotechnology 6, 343 (2011). Nanotechnology 6, 343 (2011). users.physik.fu-berlin.de/~pascual/.../SS20314-Lesung%2010d.PDF users.physik.fu-berlin.de/~pascual/.../SS20314-Lesung%2010d.PDF http://insti.physics.sunysb.edu/physics/forms/profilesearch.cgi? http://insti.physics.sunysb.edu/physics/forms/profilesearch.cgi? lastname=Averin&firstname=Dmitri lastname=Averin&firstname=Dmitri 15. Biswadeep das Sankhasubhra Sengupta Arghya Acharjee Ishika Biswas13000310065 13000310091 13000310104 13000310109