295 research outputs found
Formula SAE Hybrid Carbon Fiber Monocoque / Steel Tube Frame Chassis
The Cal Poly Formula SAE Team created this project in order to design and fabricate a high-performance chassis which would be competitive at 2013 FSAE Lincoln, and to document the process so that future teams could more easily create a chassis. One of the main goals was to reduce weight from the 143- lb 2012 chassis subsystem. A weight of 95 lb was achieved, with 82 lb in the chassis structure itself and a predicted torsional stiffness of 1700 lb*ft/deg. Composite materials design and manufacturing techniques were developed during the project. Design, testing, and manufacturing processes are detailed, and results and future work are discussed
Composite QDrift-Product Formulas for Quantum and Classical Simulations in Real and Imaginary Time
Recent work has shown that it can be advantageous to implement a composite
channel that partitions the Hamiltonian for a given simulation problem into
subsets and such that , where the terms in are simulated
with a Trotter-Suzuki channel and the terms are randomly sampled via the
QDrift algorithm. Here we show that this approach holds in imaginary time,
making it a candidate classical algorithm for quantum Monte-Carlo calculations.
We upper-bound the induced Schatten- norm on both imaginary-time
QDrift and Composite channels. Another recent result demonstrated that
simulations of Hamiltonians containing geometrically-local interactions for
systems defined on finite lattices can be improved by decomposing into
subsets that contain only terms supported on that subset of the lattice using a
Lieb-Robinson argument. Here, we provide a quantum algorithm by unifying this
result with the composite approach into ``local composite channels" and we
upper bound the diamond distance. We provide exact numerical simulations of
algorithmic cost by counting the number of gates of the form and
to meet a certain error tolerance . We show constant
factor advantages for a variety of interesting Hamiltonians, the maximum of
which is a fold speedup that occurs for a simulation of Jellium.Comment: 49 pages, 13 figure
3-D IR imaging with uncooled GaN photodiodes using nondegenerate two-photon absorption
We utilize the recently demonstrated orders of magnitude enhancement of
extremely nondegenerate two-photon absorption in direct-gap semiconductor
photodiodes to perform scanned imaging of 3D structures using IR femtosecond
illumination pulses (1.6 um and 4.93 um) gated on the GaN detector by sub-gap,
femtosecond pulses. While transverse resolution is limited by the usual imaging
criteria, the longitudinal or depth resolution can be less than a wavelength,
dependent on the pulsewidths in this nonlinear interaction within the detector
element. The imaging system can accommodate a wide range of wavelengths in the
mid-IR and near-IR without the need to modify the detection and imaging
systems.Comment: 9 pages, 6 figure
Narrow spectrum kinase inhibitors demonstrate promise for the treatment of dry eye disease and other ocular inflammatory disorders
Observation of Nondegenerate Two-Photon Gain in GaAs
Two-photon lasers require materials with large two-photon gain (2PG)
coefficients and low linear and nonlinear losses. Our previous demonstration of
large enhancement of two-photon absorption in semiconductors for very different
photon energies translates directly into enhancement of 2PG. We experimentally
demonstrate nondegenerate 2PG in optically excited bulk GaAs via femtosecond
pump-probe measurements. 2PG is isolated from other pump induced effects
through the difference between measurements performed with parallel and
perpendicular polarizations of pump and probe. An enhancement in the 2PG
coefficient of nearly two orders-of-magnitude is reported. The results point a
possible way toward two-photon semiconductor lasers.Comment: 5 pages, 5 figure
- …