title: Coherent optical spectroscopy of a strongly driven quantum dot.
abstract: Quantum dots are typically formed from large groupings of atoms and thus may be expected to have appreciable many-body behavior under intense optical excitation. Nonetheless, they are known to exhibit discrete energy levels due to quantum confinement effects. We show that, like single-atom or single-molecule two- and three-level quantum systems, single semiconductor quantum dots can also exhibit interference phenomena when driven simultaneously by two optical fields. Probe absorption spectra are obtained that exhibit Autler-Townes splitting when the optical fields drive coupled transitions and complex Mollow-related structure, including gain without population inversion, when they drive the same transition. Our results open the way for the demonstration of numerous quantum level-based applications, such as quantum dot lasers, optical modulators, and quantum logic devices.
authors: H. M. Randall Laboratory of Physics, University of Michigan, Ann Arbor, MI 48109, USA.
authors: Xiaodong
authors: X
authors: Xu
authors: Bo
authors: B
authors: Sun
authors: Paul R
authors: PR
authors: Berman
authors: Duncan G
authors: DG
authors: Steel
authors: Allan S
authors: AS
authors: Bracker
authors: Dan
authors: D
authors: Gammon
authors: L J
authors: LJ
authors: Sham