Berlin 2015 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
TT: Fachverband Tiefe Temperaturen
TT 103: Transport: Poster Session
TT 103.5: Poster
Donnerstag, 19. März 2015, 15:00–18:00, Poster B
Long-range transfer of spin qubits — •Rafael Sánchez1, Ghislain Granger2, Louis Gaudreau2, Fernando Gallego-Marcos1, Michel Pioro-Ladrière3, Sergei A. Studenikin2, Andrew S. Sachrajda2, and Gloria Platero1 — 1Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), Spain — 2NRC, Ottawa, Canada — 3Université de Sherbrooke, Canada
Quantum mechanics allows for superpositions of indirectly coupled states even if the intermediate states are far in energy. In transport, this enables long-range charge transfer through quantum dot chains [1,2]. We present the first evidence of long-range transfer of a spin qubit in a triple quantum dot [3]. This process is detected via a very narrow resonance in the current through the system at the degeneracy point of three-electron charge configurations (2,0,1) and (1,0,2). There, an electron is delocalized between the two dots without ever occupying the center dot. Of the two electrons forming a spin singlet in one dot, only the one with a spin opposite to that of the electron in the other edge dot will be allowed to tunnel. The emptiness of the centre dot warranties the conservation of the spin of the tunneling electron. Thus, the long-range electron tunneling between edges enables the long-range transfer of an arbitrary spin state (the qubit) in the opposite direction.
[1] M. Busl et al., Nature Nanotech. 8, 261 (2013).
[2] R. Sánchez et al., Phys. Rev. B 89, 161402(R) (2014).
[3] R. Sánchez et al., Phys. Rev. Lett. 112, 176803 (2014)