title: A digital laser for on-demand laser modes.
abstract: Customizing the output beam shape from a laser invariably involves specialized optical elements in the form of apertures, diffractive optics and free-form mirrors. Such optics require considerable design and fabrication effort and suffer from the further disadvantage of being immutably connected to the selection of a particular spatial mode. Here we overcome these limitations with the first digital laser comprising an electrically addressed reflective phase-only spatial light modulator as an intra-cavity digitally addressed holographic mirror. The phase and amplitude of the holographic mirror may be controlled simply by writing a computer-generated hologram in the form of a grey-scale image to the device, for on-demand laser modes. We show that we can digitally control the laser modes with ease, and demonstrate real-time switching between spatial modes in an otherwise standard solid-state laser resonator. Our work opens new possibilities for the customizing of laser modes at source.
authors.affiliation: School of Physics, University of KwaZulu-Natal, Private Bag X54001, Durban 4000, South Africa.
authors.forename: Sandile
authors.initials: S
authors.lastname: Ngcobo
authors.forename: Igor
authors.initials: I
authors.lastname: Litvin
authors.forename: Liesl
authors.initials: L
authors.lastname: Burger
authors.forename: Andrew
authors.initials: A
authors.lastname: Forbes