190 research outputs found
Exactly solvable -symmetric models in two dimensions
Non-hermitian, -symmetric Hamiltonians, experimentally realized
in optical systems, accurately model the properties of open, bosonic systems
with balanced, spatially separated gain and loss. We present a family of
exactly solvable, two-dimensional, potentials for a
non-relativistic particle confined in a circular geometry. We show that the
symmetry threshold can be tuned by introducing a second
gain-loss potential or its hermitian counterpart. Our results explicitly
demonstrate that breaking in two dimensions has a rich phase
diagram, with multiple re-entrant symmetric phases.Comment: 6 pages, 6 figure
High Performance Power Spectrum Analysis Using a FPGA Based Reconfigurable Computing Platform
Power-spectrum analysis is an important tool providing critical information
about a signal. The range of applications includes communication-systems to
DNA-sequencing. If there is interference present on a transmitted signal, it
could be due to a natural cause or superimposed forcefully. In the latter case,
its early detection and analysis becomes important. In such situations having a
small observation window, a quick look at power-spectrum can reveal a great
deal of information, including frequency and source of interference. In this
paper, we present our design of a FPGA based reconfigurable platform for high
performance power-spectrum analysis. This allows for the real-time
data-acquisition and processing of samples of the incoming signal in a small
time frame. The processing consists of computation of power, its average and
peak, over a set of input values. This platform sustains simultaneous data
streams on each of the four input channels.Comment: 5 pages, 3 figures. Published in the Proceedings of the IEEE
International conference on Reconfigurable Computing and FPGAs (ReConFig
2006). Article also available at
http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4100006&isnumber=409995
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