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From transistors to quantum dots
1954 First transistor radio’s 1947 First transistor
Lieven Vandersypen Spin Qubit From transistors to quantum dots - - PowerPoint PPT Presentation
Lieven Vandersypen Spin Qubit From transistors to quantum dots - - PowerPoint PPT Presentation
Lieven Vandersypen Spin Qubit From transistors to quantum dots 1947 First transistor 1954 First transistor radios From transistors to quantum dots 1958 First integrated circuit 1989 Intel 486 processor Low temperature operation Single
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SLIDE 3
From transistors to quantum dots
1958 First integrated circuit 1989 Intel 486 processor
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Low temperature operation
Single electron charging energy EC = e2/C, (C=8ereoR, disk) R = 10 nm EC = 30 meV R = 100 nm EC = 3 meV Thermal energy T = 300 K kBT ~ 26 meV T = 4.2 K kBT ~ 0.35 meV T = 30 mK kBT ~ 2.6 ueV Operation is at low temperatures Dilution refrigerators reach temperatures below 10mk
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Quantum dots
- Energy an electron needs to
have in order to enter the dot.
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Quantum dots
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Charge sensing
- A quantum dot can also be a
very sensitive electrometer.
- See single electrons jump on/off in
real time.
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Quantum dot system
Gate 1 Gate 2
B2 G2 G1 B1 B3
Barrier 2
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Two coupled quantum dots
2DEG Al Ga As X 1-X GaAs Ohms contact naar 2DEG gatesB2 G2 G1 B1 B3
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Two coupled quantum dots
B2 G2 G1 B1 B3
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Two coupled quantum dots
Extra electron in one dot shifts levels of other dot
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From transistors to many quantum dots
Industrial involvement
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