Possible applications of SET

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Lecture 16 Possible applications of SET
Spintronics end spin filres

• Other names
• Single-electron tunneling (SET) transistors
• Quantum dots
• Zero-dimensional electron gas
• Coulomb islands
• These are different names for the same type of
  structure, which includes two big electrodes with
  a nanoparticle of some sort placed between these
  electrons and helping electrons to flow from one
  electrode to the other

Coulomb island or quantum dot
source
drain
gate
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Applications of spintronics
Spintronics is a new branch of electronics in
which electron spin, in addition to charge, is
manipulated to yield a desired outcome. All
spintronic devices act according to the simple
scheme (1) information is stored (written) into
spins as a particular spin orientation (up or
down), (2) the spins, being attached to mobile
electrons, carry the information along a wire,
and (3) the information is read at a terminal.
Spin orientation of conduction electrons survives
for a relatively long time (nanoseconds, compared
to tens of femtoseconds during which electron
momentum decays), which makes spintronic devices
particularly attractive for memory storage and
magnetic sensors applications, and, potentially
for quantum computing where electron spin would
represent a quantum bit of information, called
qubit.
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single-electron-tunneling (SET) transistor with
ferromagnetic leads (Spintronics applications of
SET)
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Single Coulomb peaks
explained by Averin-Likharev or Orthodox
theory
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Principle of SET transistor
M. Kastner, 1992
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SET principle
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First single-electron transistor
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Nanotubes can be used to make SET transistors
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Delft experiment on SET with nanotubes Charge
noise is clearly observed on the figure
2b Charge noise is the most important problem
which slows don the application of SET devices in
computers
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Delft experiment-continues
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multi-probe SET device involving a single nanotube
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multi-probe SET device involving a single
nanotube (multiple islands)
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multi-probe SET device involving a single
nanotube (multiple islands)
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Parity effects in superconducting SET transistors
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IV curves of a superconducting SET transistors
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Current versus gate voltage of a superconducting
SET transistors
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parity effects
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SET transistors with Cooper pairs (Tuominen et al)
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Nature, 407, 57 (2000)
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