High-efficiency measurement of all orbital angular momentum modes in a light beam

@article{Rathore2016HighefficiencyMO,
  title={High-efficiency measurement of all orbital angular momentum modes in a light beam},
  author={Haad Yaqub Rathore and Mumtaz Sheikh and Usman A. Javid and Hamza Ahmed and Syed Azer Reza},
  journal={Journal of The Optical Society of America B-optical Physics},
  year={2016},
  volume={34},
  pages={1444-1449}
}
We present an experimental demonstration of a Laguerre–Gauss (LG) spectrum measurement technique using variable focus lenses that is able to measure the strengths of the constituent modes in an unknown incoming light beam with the highest possible efficiency. The experiment modifies the classical projective, phase flattening technique by including a variable-sized pinhole and a two-electronic-lens variable imaging system that is tuned for each mode to give the highest possible detection… 

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References

SHOWING 1-10 OF 29 REFERENCES

Limitations to the determination of a Laguerre–Gauss spectrum via projective, phase-flattening measurement

One of the most widely used techniques for measuring the orbital angular momentum (OAM) components of a light beam is to flatten the spiral phase front of a mode, in order to couple it to a

Rapid generation of light beams carrying orbital angular momentum.

We report a technique for encoding both amplitude and phase variations onto a laser beam using a single digital micro-mirror device (DMD). Using this technique, we generate Laguerre-Gaussian and

Measurement of the light orbital angular momentum spectrum using an optical geometric transformation

We recently demonstrated a new method to efficiently analyse the orbital angular momentum (OAM) states of light by application of an optical geometric transformation (Berkhout et al 2010 Phys. Rev.

High-efficiency phase flattening based Laguerre–Gauss spectrometer using variable focus lenses

We propose a novel high-efficiency no-moving-parts Laguerre–Gauss (LG) spectrometer using two variable focus lenses and a variable-sized pinhole that overcomes the limitations of the classical,

Free-space information transfer using light beams carrying orbital angular momentum.

The transfer of information encoded as orbital angular momentum states of a light beam is demonstrated, which is resistant to eavesdropping and gives an experimental insight into the effects of aperturing and misalignment of the beam on the OAM measurement and demonstrates the uncertainty relationship for OAM.

Measurement of the orbital angular momentum density of light by modal decomposition

We demonstrate a versatile method for the measurement of the orbital angular momentum (OAM) density of an optical field. By performing a modal decomposition with digital holograms, we reconstruct the

Efficient generation and sorting of orbital angular momentum eigenmodes of light by thermally tuned q-plates

We present methods for generating and for sorting specific orbital angular momentum (OAM) eigenmodes of a light beam with high efficiency, using a liquid crystal birefringent plate with unit

Efficient sorting of orbital angular momentum states of light.

A method to efficiently sort orbital angular momentum states of light using two static optical elements that perform a Cartesian to log-polar coordinate transformation, converting the helically phased light beam corresponding to OAM states into a beam with a transverse phase gradient.

Efficient separation of the orbital angular momentum eigenstates of light.

A method is demonstrated which uses a series of unitary optical transformations to enable the measurement of light's OAM with an experimental separation efficiency of >92%, which makes it particularly attractive for enhancing the information capacity of multi-level quantum cryptography systems.

Observation of the orbital angular momentum spectrum of a light beam.

An experimental scheme is demonstrated that allows the elucidation of the orbital angular momentum discrete spectrum of an arbitrary light signal by exploiting the Doppler frequency shift that is imparted to rotating light beams.