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Updated: Jun 19, 2026
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Measurement of Quantum Interference in a Silicon Ring Resonator Photon Source
Published on: April 4, 2017
Experimental determination of number-phase uncertainty relations
Optics Letters
|October 14, 2009
Summary
Researchers experimentally verified the quantum uncertainty principle for light. They measured the phase and photon number uncertainty product, confirming quantum mechanics predictions for electromagnetic fields.
Area of Science:
- Quantum optics
- Quantum mechanics
- Electromagnetic field theory
Background:
- The Heisenberg uncertainty principle is a fundamental concept in quantum mechanics.
- It states that certain pairs of physical properties, like phase and photon number for a light mode, cannot be simultaneously known with arbitrary precision.
- Experimental verification is crucial for understanding quantum phenomena.
Purpose of the Study:
- To experimentally determine the uncertainty product for the phase and photon number of a light mode.
- To experimentally measure the expectation value of the commutator, which defines the lower bound of this uncertainty product.
- To validate quantum mechanical predictions through empirical data.
Main Methods:
- Utilizing optical homodyne tomography to reconstruct the quantum state of light.
- Measuring the density matrix of a small-photon-number coherent state.
- Performing experimental calculations of the uncertainty product and commutator expectation value.
Main Results:
- The experimental uncertainty product for phase and photon number was determined.
- The expectation value of the commutator was measured.
- The obtained experimental results align with theoretical quantum mechanical predictions.
Conclusions:
- The experiment successfully verified the quantum uncertainty principle for the electromagnetic field.
- Optical homodyne tomography is a viable method for probing quantum states and their uncertainties.
- The findings reinforce the validity of quantum mechanics in describing light-matter interactions.
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