Journal of Low Temperature Physics

, Volume 118, Issue 5–6, pp 751–763 | Cite as

Nano-Electronic Realizations of Quantum Bits

  • Yuriy Makhlin
  • Gerd Shön
  • Alexander Shnirman


Quantum computers could perform certain tasks which noclassical computer can perform in acceptable times. Josephsonjunction circuits can serve as building blocks of quantumcomputers. We discuss and compare two designs, which employcharge or magnetic flux degrees of freedom to process quantuminformation. In both cases, elementary single-qubit and two-qubit logic gates can be performed by voltage or flux pulses.The coherence time is long enough to allow a series of suchoperations. We also discuss the read-out, i.e. a quantummeasurement process. In the charge case it is accomplished bycoupling a single-electron transistor to the qubit.


Coherence Building Block Magnetic Material Magnetic Flux Quantum Computer 
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Copyright information

© Plenum Publishing Corporation 2000

Authors and Affiliations

  • Yuriy Makhlin
    • 1
    • 2
  • Gerd Shön
    • 1
    • 3
  • Alexander Shnirman
    • 1
  1. 1.Institut für Theoretische FestkörperphysikUniversität KarlsruheKarlsruheGermany
  2. 2.Landau Institute for Theoretical PhysicsMoscowRussia
  3. 3.Forschungszentrum Karlsruhe, Institut für NanotechnologieKarlsruhe

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