Single-exciton energy shell structure in InAs/GaAs quantum dots

Article

关键词: MAGNETIC-FIELD;    EXCITATION SPECTROSCOPY;    OPTICAL-PROPERTIES;    ELECTRON;    PHOTOLUMINESCENCE;    MAGNETOOPTICS;    RELAXATION;    ABSORPTION;    ATOMS;    POWER;   

DOI  :  10.1103/PhysRevB.78.235313

来源: SCIE

【 摘 要 】

The energy shell structure of a single exciton confined in a self-assembled quantum dot (QD), including excited states, is studied in a regime where the direct Coulomb attraction energy is comparable to the kinetic energy of the carriers. This is achieved via magnetophotoluminescence excitation spectroscopy experiments, where a magnetic field applied perpendicular to the plane of the QD is used to reveal the angular-momentum content of energy shells. The absorption spectrum of the QDs is modeled, and comparison with experiment allows us to relate the observed transitions to interband QD bound-state transitions. The blueshift of the absorption peaks compared to the emission peaks is then interpreted in terms of many-body interactions, and we show that for a highly symmetric situation, the observed energy difference gives a direct measurement of the extra exchange energy gained upon addition of an extra exciton in the QD.

【 授权许可】

Free