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Direct detection of a single photon by humans
Jonathan N Tinsley1,2, Maxim I Molodtsov1,2,3, Robert Prevedel1,2,3
1Research Institute of Molecular Pathology, Dr Bohr-Gasse 7, 1030 Vienna, Austria.
Nature Communications
|July 20, 2016
Summary
Humans can detect a single photon incident on the eye, a long-standing question in vision science. This detection is enhanced by a recent photon, suggesting a temporary boost in visual system sensitivity.
Area of Science:
- Vision science
- Neuroscience
- Quantum physics
Background:
- The absolute limits of human vision, particularly concerning single-photon detection, remain largely uncharacterized despite decades of research.
- Rod cells' ability to respond to individual photons raises the question of whether perception is possible at this fundamental level.
Purpose of the Study:
- To determine if humans can perceive a single photon incident on the cornea.
- To investigate the potential modulation of single-photon detection by prior light exposure.
Main Methods:
- Employed a psychophysics procedure combined with a quantum light source capable of generating single-photon states.
- Quantified the probability of detecting a single photon above chance levels.
Main Results:
- Demonstrated that humans can detect a single photon incident on the cornea with a probability significantly above chance.
- Observed that the detection probability of a single photon is influenced by the prior presence of another photon.
Conclusions:
- Human visual perception is possible at the single-photon level.
- A priming process temporarily enhances visual system gain on a second-scale, modulating single-photon detection probability.
