Tunneling-induced dephasing in InP quantum dots

We observed the tunneling process of photo-excited holes in neutral InP quantum dots and Pauli blocking of charged InP quantum dots. A highly sensitive heterodyne-detected photon echo method enabled us to observe the signal from one layer of self-assembled InP quantum dots under the electric field. The electric field could control the charging or neutralization of the InP quantum dots and hence the photon echo signal decreased considerably with the increase of electron doping. The photon echo of neutral InP quantum dots under the electric field showed tunneling-induced dephasing, which decays non-exponentially reflecting the non-Markovian nature of the tunneling process.