Long-lived quantum coherence in a two-level semiconductor quantum dot

Eduardo Vaz, Jordan Kyriakidis

K. Berrada

Hidehiko Kamada, Hideki Gotoh, Hiroaki Ando +2 more

Potential application of elementary excitation in semiconductor quantum dot to quantum computation is discussed. Construction of scalable hardware and all optical implementation of logical gate that exploits discrete nature of electron-hole states and their well concentrated oscillator strenth for ultrafast gate operation are proposed. Rabi population oscillation of an excitonic two-level system in an isolated single InxGa1-xAs quantum dot is manifested by a quantum wave function interferometry in time domain, demonstrating a long lived coherence of zero-dimensional excitonic states and revealed the coherent population flopping under strong optical field. A phase-sensitive coherent gate operation on single-dot exciton qubit is demonstrated.

Hidehiko Kamada, Hideki Gotoh

Potential application of elementary excitation in semiconductor quantum dot to quantum computation is discussed. We propose a scalable hardware and all optical implementation of a logic gate that exploits the discrete nature of electron–hole states and their well-concentrated oscillator strength for ultrafast gate operation. A multiple-bit gate function is based on the nearest neighbour dipole–dipole coupling. Rabi population oscillation and long-lived coherence of an excitonic two-level system in an isolated InxGa1−xAs quantum dot guarantees quantum gate functions. Technologies that will realize and facilitate the exciton quantum computing are discussed.

Junko Ishi‐Hayase