Media 1: Stand-alone system for high-resolution, real-time terahertz imaging

Originally published in Optics Express on 30 January 2012 (oe-20-3-2772

Media 3: Stand-alone system for high-resolution, real-time terahertz imaging

Originally published in Optics Express on 30 January 2012 (oe-20-3-2772

Media 2: Stand-alone system for high-resolution, real-time terahertz imaging

Originally published in Optics Express on 30 January 2012 (oe-20-3-2772

Media 4: Stand-alone system for high-resolution, real-time terahertz imaging

Originally published in Optics Express on 30 January 2012 (oe-20-3-2772

Terahertz Quantum Cascade Lasers based on two-dimensional photonic crystal resonators

We demonstrate high spectral control from surface emitting THz Quantum Cascade Lasers based on a two-dimensional photonic crystal cavity. The perforated top metallic contact acts as an in plane resonator in a tight double-metal plasmonic waveguide providing a strong optical feedback without needing three-dimensional cavity features. The optical far-field patterns do not exhibit the expected symmetry and the shape of the cavity mode. The difference is attributed to a metal surface plasmon mediated light outcoupling mechanism also responsible for the relatively low extraction efficiency. (C) 2008 Optical Society of America

Bound-to-continuum terahertz quantum cascade laser with a single-quantum-well phonon extraction/injection stage

A terahertz quantum cascade laser design that combines a wide gain bandwidth, large photon-driven transport and good high-temperature characteristics is presented. It relies on a diagonal transition between a bound state and doublet of states tunnel coupled to the upper state of a phonon extraction stage. The high optical efficiency of this design enables the observation of photon-driven transport over a wide current density range. The relative tolerance of the design to small variations in the barrier thicknesses made it suitable for testing different growth techniques and materials. In particular, we compared the performances of devices grown using molecular-beam epitaxy with those achieved using organometallic chemical vapor deposition. The low-threshold current density and the high slope efficiency makes this device an attractive active region for the development of single-mode quantum cascade lasers based on third-order-distributed feedback structures. Single-mode, high power was achieved with good continuous and pulsed wave operation.ISSN:1367-263

Broadband Biphoton Generation and Polarization Splitting in a Monolithic AlGaAs Chip

The ability to combine various advanced functionalities on a single chip is a key issue for both classical and quantum photonic-based technologies. On-chip generation and handling of orthogonally polarized photon pairs, one of the most used resources in quantum information protocols, is a central challenge for the development of scalable quantum photonics circuits; in particular, the management of spectrally broadband biphoton states, an asset attracting growing attention for its capability to convey large-scale quantum information in a single spatial mode, is missing. Here, we demonstrate a monolithic AlGaAs chip, including the generation of broadband orthogonally polarized photon pairs and their polarization splitting; 85% of the pairs are deterministically separated by the chip over a 60 nm bandwidth. The quality of the two-photon interference at the chip output is assessed via a Hong–Ou–Mandel experiment displaying a raw visibility of 75.5% over the same bandwidth. These results, obtained for the first time at room temperature and telecom wavelength, in a platform combining strong confinement, high second-order nonlinearity, electro-optic effect, and direct bandgap, confirm the validity of our approach and represent a significant step toward miniaturized and easy-to-handle photonic devices working in the broadband regime for quantum information processing