Electron cooling times in PbTe Landau quantized wires and dots

We present measurements of electron cooling times in `quasi' quantum wires and dots as a function of the z-confinement. The states were created by application of a magnetic field along the growth direction of bulk material, a wide parabolic well and a narrow quantum well, based on the IV-VI material PbTe. These three systems thus provide a progression of successively 1D-like, weakly 0D-like and 0D-like density of states. The measurements were all made above the LO-phonon energy, and the increasing confinement is represented in the LO-phonon cooling times observed, which become successively longer.