Strong electron-hole exchange in coherently coupled quantum dots.
We have investigated few-body states in vertically stacked quantum dots. Because of a small interdot tunneling rate, the coupling in our system is in a previously unexplored regime where electron-hole exchange plays a prominent role. By tuning the gate bias, we are able to turn this coupling off and study a complementary regime where total electron spin is a good quantum number. The use of differential transmission allows us to obtain unambiguous signatures of the interplay between electron and hole-spin interactions. Small tunnel coupling also enables us to demonstrate all-optical charge sensing, where a conditional exciton energy shift in one dot identifies the charging state of the coupled partner.
Fält
Stefan
S
Institute of Quantum Electronics, ETH Zurich, 8093 Zurich, Switzerland.
Atatüre
Mete
M
Türeci
Hakan E
HE
Zhao
Yong
Y
Badolato
Antonio
A
Imamoglu
Atac
A