Seminar: Igor Khanonkin

Light – matter interactions in room-temperature quantum dot ensembles

Zero dimensional materials, or quantum dots (QDs), have attracted major interest in recent decadesboth in fundamental physics and in varies device applications. Self-assembled QDs exhibit atomiclikediscrete energy levels and delta-function density of states.Semiconductor QD ensembles behave as a cascaded collection of effective two-level systems,facilitating an optical gain material with vastly improved characteristics compared to higherdimensional materials. Hereof, a new generation of record homogeneous QD lasers exhibit a narrowlinewidth, temperature insensitive, low threshold currents operation. Additionally, we have recentlydeveloped a tunneling injection scheme in QD laser that solved the hot carrier injection problem andimproved the dynamical properties of QD lasers.Furthermore, QDs have become a prominent platform as a solid-state technology in quantuminformation processing applications. We have employed room-temperature QD ensembles with subpicosecondcoherence time as a basis for quantum optics application. Using ultra-fast optics tools, wehave demonstrated Rabi oscillation, Ramsey interference, photon echo and revival of quantumcoherence, induced and controlled in an ensemble of QDs operating at room temperature and telecomwavelength.