English

Quantum-enhanced absorption spectroscopy

Quantum Physics 2017-02-22 v1

Abstract

Absorption spectroscopy is routinely used to characterise chemical and biological samples. For the state-of-the-art in absorption spectroscopy, precision is theoretically limited by shot-noise due to the fundamental Poisson-distribution of photon number in laser radiation. In practice, the shot-noise limit can only be achieved when all other sources of noise are eliminated. Here, we use wavelength-correlated and tuneable photon pairs to demonstrate sub-shot-noise absorption spectroscopy. We measure the absorption spectra of spectrally-similar biological samples---oxyhaemoglobin and carboxyhaemoglobin---and show that obtaining a given precision in resolution requires fewer heralded single probe photons compared to using an ideal laser.

Keywords

Cite

@article{arxiv.1508.00849,
  title  = {Quantum-enhanced absorption spectroscopy},
  author = {Rebecca Whittaker and Chris Erven and Alex Neville and Monica Berry and Jeremy L. O'Brien and Hugo Cable and Jonathan C. F. Matthews},
  journal= {arXiv preprint arXiv:1508.00849},
  year   = {2017}
}

Comments

5 pages, 4 figures

R2 v1 2026-06-22T10:26:21.323Z