Towards quantum communication with electron spins

• Published in: Turkish journal of physics 2003, Vol.27 (5), p.427-441
• Main Authors: SARAGA. D.S, LOSS, D, EGUES, J. C, RECHER, P, ENGEL, H. A, BURKARD, G
• Format: Article
• Language: English
• Subjects: communication; Coulomb etkileşimi; Coulomb interaction; Decoherence; electron spin; Elektron spini; Experimental Methods and Instrumentation for Particle and Nuclear Physics; Eşevresizlik; İletişim; Kuantum bilgisayar; Kuantum noktası; Kubit; Physics of Elementary Particles and Fields; Quantum computer; quantum dot; Qubit; Temel Parçacık ve Alan Fiziği; Temel Parçacık ve Nükleer Fizik Deney Yöntemleri ve Aletsel Uygulamaları
• ISSN: 1300-0101

We review our recent work towards quantum communication in a solid-state environment with qubits carried by electron spins. We propose three schemes to produce spin-entangled electrons, where the required separation of the partner electrons is achieved via Coulomb interaction. The non-product spinstates originate either from the Cooper pairs found in a superconductor, or in the ground state of a quantum dot with an even number of electrons. In a second stage, we show how spin-entanglement carried by a singlet can be detected in a beam-splitter geometry by an increased (bunching) or decreased (antibunching) noise signal. We also discuss how a local spin-orbit interaction can be used to provide a continuous modulation of the noise as a signature of entanglement. Finally, we review how one can use a quantum dot as a spin-filter, a spin-memory read-out, a probe for single-spin decoherence and, ultimately, a single-spin measurement apparatus.