No abstract

We report the first experimental investigation of the spectral response of a "bulk microcavity": a semiconductor system in which the same cavity material is the active medium.Despite the smaller oscillator strength of the bulk exciton, a Rabi splitting even clearer than that displayed by usual quantum-well microcavities is observed. The splitting increases with the cavity layer thickness and the exciton dispersion produces a satellite structure due to quantum confinement. We also show that control of the exciton-photon interaction can be realized by suitably tailoring the photonic wave function. PACS numbers: '7]. 36.+c, 42.50.p, 71.35.+z, 73.20.Dx In the last few years, the study of quantum microcavities has fascinated many researchers, mainly because, by altering the photonic density of states, these structures allow the investigation of fundamental quantum electrodynamics and are ideal candidates for new optical devices. The first experiments were performed in the field of atomic physics [1],but presently a great interest has surged in the semiconductor world because solid-state cavities with Bragg reflectors as mirrors can now be produced by standard growing techniques such as molecular beam epitaxy (MBE) or met-

The conduction band offset in ZnSe/GaAs n-p heterodiodes was determined from measurements of the low-temperature tunneling current of photoinjected carriers. We found widely different discontinuities for heterojunctions fabricated with different Zn/Se flux ratios, with conduction band offsets as high as 0.75 eV for Se-rich interfaces, and as low as 0.26 eV for Zn-rich interfaces.

No abstract