The approach is to use appropriately doped semi-insulating gallium nitride to provide a high damage tolerant photoconductor with high responsivity to various pump wavelength light.  Mn, C, or Fe are used as dopants to provide a source of electrons or holes that can be excited.  This is combined with the use of dichroic antireflection coating at the GaN/polyimide/liquid crystal…

This invention works by imaging an ultrafast pulse diffracted from a large grating onto a spatial light modulator (SLM) thereby directly transcribing an arbitrary record on a pulse front tilted (PFT) ultrafast pulse. The grating generates PFT of the input pulse, and the SLM provides temporal control of the pulse through the space-to-time mapping of the tilted pulse. Coupling this patterned…

This invention proposes using a pulse laser configured to generate laser pulses and a controller for controlling operation of the pulse laser. The controller is further configured to control the pulse laser to cause the pulse laser to generate at least one of the laser pulses with a spatiotemporally varying laser fluence over a duration of at least one of the laser pulses. The spatiotemporally…

This invention proposes to engineer the current density along the length of a laser diode to overcome the penalty associated with non-uniformity resulting from asymmetry in the gain, photon or carrier density despite having uniform contact. Optimizing the current density profile enables diode lasers to operate with greater power conversion efficiency or operate with equivalent power conversion…

This invention proposes a method to overcome the key limitation of electrically pumped lasers based on AlN, AlGaN, or AlInGaN, namely the lack of suitable shallow donor and acceptor dopants. As the band gap of these materials increases (and the emission wavelength decreases), both electrons and holes require greater thermal energies in order to ionize.

Laser diode lensing effect can be substantially reduced by creating a pattern interface such that the substrate is only attached at the diode mesa. This is achieved by either creating a pattern solder joint and/or pattern substrate.

This invention is about a Material Jetting technique used to form a ceramic green body that is subsequently processed into a transparent ceramic optic with unique tunable spatial control of the composition as a function of position only achievable via additive manufacturing methods. This method uses ceramic particles loaded into a liquid slurry with required viscosity and surface tension to be…

This LLNL invention proposes a novel approach to spectral interferometry, the preferred technique for characterizing nanosecond long records of laser pulse shapes with femtosecond resolution. Linear techniques are much more sensitive than the many nonlinear techniques of the prior art and can be used for very weak pulses. However, they depend on being able to interfere the signal with a well…

LLNL researchers in the NIF Directorate DoD Technologies RF Photonics Group explored phase modulation solutions to this signal processing challenge. Optical frequency combs offer phase noise characteristics that are orders of magnitude lower than available from commercial microwave references. The Photonics Group researchers recognized that by converting the intensity information into phase,…