2006/12/08 by Taras Plakhotnik, Plakhotnik, Taras
Biochemistry, Genetics and Molecular Biology · Computer Science · Engineering · Physics and Astronomy · #FOS: Physical sciences #Near-Field Optical Microscopy #Optics (physics.optics) #Quantum Information and Cryptography #Spectroscopy Techniques in Biomedical and Chemical Research #physics.optics
paper · pdf · doi:10.48550/arxiv.physics/0612078
12 pages incl 3 figures
arxiv created 2006/12/08 · openalex publication_date 2006/12/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The ultimate sensitivity of optical detection is limited by the signal-to-noise ratio (SNR). The first part of the paper shows that coherence plays an important role in the noise analysis. Although interference between an auxiliary wave and a signal wave makes the photo detector response to the signal stronger, the coherent noise also enhances. This makes insignificant the gain in the SNR. Pulsed-excitation gated-detection (PEGD) is described and analyzed in the second part to show that 1) a high brightness of detected particles is not a prerequisite for a high SNR, 2) optimized parameters of the PEGD protocol demonstrate interesting bifurcation making a sudden jump from an effectively continuous regime to PEGD, and 3) photo-physical properties of NV centers in nano crystals of diamond approach those ideal for PEGD.