title: Selective generation of ultracold high-density 1s orthoexcitons in Cu2O with phase-modulated pulse using acousto-optic programmable filter.
abstract: Ultracold and high-density 1s orthoexcitons in semiconductor cuprous oxide are prepared via resonant two-photon absorption of a phase-tailored femtosecond pulse, by utilizing an acousto-optic programmable dispersive filter. The stability of the quantum degenerate exciton gas is studied using excitonic Lyman spectroscopy. A density of 10(16) cm(-3) is realized without creating hot carriers, and the Lyman spectrum remains unchanged at this density. This result assures the stability of a spontaneous Bose-Einstein condensate of excitons at sub-Kelvin temperatures.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Yoshioka
authors.forename: Ken
authors.initials: K
authors.lastname: Miyashita
authors.forename: Makoto
authors.initials: M
authors.lastname: Kuwata-Gonokami