Ultrafast pump-probe spectroscopy and pulse-shaping techniques are providing new modes of contrast for the field of
multiphoton microscopy. Endogenous species such as heme proteins show rich nonlinear spectroscopic signatures of
excited state absorption, stimulated emission and ground-state bleaching. Commercially available octave-spanning
Ti:sapphire oscillators offer new opportunities for imaging based on pump-probe contrast. Spatial light modulators take
advantage of this large bandwidth, shaping pulses of light to selectively excite molecular structures with similar spectral
properties. We present two-color pump-probe imaging of heme proteins solutions and red blood cells.
We demonstrate a balanced-homodyne LADAR receiver employing a phase-sensitive amplifier (PSA) to raise the
effective photon detection efficiency (PDE) to nearly 100%. Since typical LADAR receivers suffer from losses in the
receive optical train that routinely limit overall PDE to less than 50% thus degrading SNR, PSA can provide significant
improvement through amplification with noise figure near 0 dB. Receiver inefficiencies arise from sub-unity quantum
efficiency, array fill factors, signal-local oscillator mixing efficiency (in coherent receivers), etc. The quantum-enhanced
LADAR receiver described herein is employed in target discrimination scenarios as well as in imaging applications. We
present results showing the improvement in detection performance achieved with a PSA, and discuss the performance
advantage when compared to the use of a phase-insensitive amplifier, which cannot amplify noiselessly.
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