3 research outputs found
Vector beams generated by microlasers based on topological liquid-crystal structures
Structured light with designable intensity, polarization and phase fields is
today of high relevance, with application ranging from imaging, metrology,
optical trapping, ultracold atoms, classical and quantum communications and
memory. Specifically, vortex and vector beams can be generated directly in the
laser cavity, however, a controllable, geometrically simple and easy to
manufacture laser microcavity that generates structured light on demand,
especially tailored polarization, is still an open challenge. Here we show that
tunable laser vector beams can be generated from self-assembled liquid-crystal
(LC) micro-structures with topological defects inside a thin Fabry-P\'erot
microcavity. The LC superstructure provides complex three dimensional
birefringent refractive index profiles with order parameter singularities. The
topology of the LC structures is transferred into the topology of the light
polarization. The oriented fluorescent dye emission dipoles enable the
selection of optical modes with a particular polarization, as enabled by the
birefringence profile in the laser cavity. The proposed lasers have no
principal limitation for realizing structured light with arbitrarily tailored
intensity and polarization fields
Benchmarking Digital-Analog Quantum Computation
Digital-Analog Quantum Computation (DAQC) has recently been proposed as an
alternative to the standard paradigm of digital quantum computation. DAQC
creates entanglement through a continuous or analog evolution of the whole
device, rather than by applying two-qubit gates. This manuscript describes an
in-depth analysis of DAQC by extending its implementation to arbitrary
connectivities and by performing the first systematic study of its scaling
properties. We specify the analysis for three examples of quantum algorithms,
showing that except for a few specific cases, DAQC is in fact disadvantageous
with respect to the digital case.Comment: 16+5 pages, 11 figure