Phenomenon of interference between two light beams propagating in optical fibers having a large path difference

We present a simple and effective experimental setup to help students visualize light rays in optics experiments. When illuminated by a blue-violet laser pointer (typical wavelength [Formula: see text][Formula: see text]nm), tonic water and phosphorescent paper show fluorescence which allows the laser beam to be clearly seen by a large audience under normal ambient lighting. The setup is particularly useful for conducting classroom demonstrations on the reflection, refraction and diffraction of light. Quantitative measurement is also possible, e.g. students can attach a transparent scale to the phosphorescent paper or container holding the tonic water, and perform a quick verification of Snell’s law and the diffraction formula [Formula: see text]. The appeal of the visualization of light beams in multiple total internal reflections and retroreflection could help teachers introduce technological applications such as optical fibers and retroreflectors in road signs. A simple but interesting experiment of scattering laser light to form a light cone in a medium is shown using the fluorescence method. Redoing or modifying other innovative optics experiments using the fluorescence method is also discussed.

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Depolarization of Light in Optical Fibers: Effects of Diffraction and Spin-Orbit Interaction

Fibers ◽

10.3390/fib9060034 ◽

2021 ◽

Vol 9 (6) ◽

pp. 34

Author(s):

Nikolai I. Petrov

Keyword(s):

Optical Fibers ◽

Berry Phase ◽

Polarization Plane ◽

Orbit Interaction ◽

Spin Orbit ◽

Tensor Polarization ◽

Spin Orbit Interaction ◽

Graded Index ◽

Depolarization Of Light ◽

Light Beams

Polarization is measured very often to study the interaction of light and matter, so the description of the polarization of light beams is of both practical and fundamental interest. This review discusses the polarization properties of structured light in multimode graded-index optical fibers, with an emphasis on the recent advances in the area of spin-orbit interactions. The basic physical principles and properties of twisted light propagating in a graded index fiber are described: rotation of the polarization plane, Laguerre–Gauss vector beams with polarization-orbital angular momentum entanglement, splitting of degenerate modes due to spin-orbit interaction, depolarization of light beams, Berry phase and 2D and 3D degrees of polarizations, etc. Special attention is paid to analytical methods for solving the Maxwell equations of a three-component field using perturbation analysis and quantum mechanical approaches. Vector and tensor polarization degrees for the description of strongly focused light beams and their geometrical interpretation are also discussed.

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Photoelectric Detection of Interference between Two Light Beams Having a Large Path Difference

Journal of the Optical Society of America ◽

10.1364/josa.51.001030 ◽

1961 ◽

Vol 51 (9) ◽

pp. 1030 ◽

Cited By ~ 25

Author(s):

M. Parker Givens

Keyword(s):

Path Difference ◽

Photoelectric Detection ◽

Light Beams

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Silica optical fiber integrated with two-dimensional materials: towards opto-electro-mechanical technology

Light Science & Applications ◽

10.1038/s41377-021-00520-x ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Jin-hui Chen ◽

Yi-feng Xiong ◽

Fei Xu ◽

Yan-qing Lu

Keyword(s):

Optical Fiber ◽

Optical Fibers ◽

2D Materials ◽

Two Dimensional ◽

Optoelectronic System ◽

Electro Optic ◽

Two Dimensional Materials ◽

Challenges And Opportunities ◽

Mechanical Devices ◽

Light Beams

AbstractIn recent years, the integration of graphene and related two-dimensional (2D) materials in optical fibers have stimulated significant advances in all-fiber photonics and optoelectronics. The conventional passive silica fiber devices with 2D materials are empowered for enhancing light-matter interactions and are applied for manipulating light beams in respect of their polarization, phase, intensity and frequency, and even realizing the active photo-electric conversion and electro-optic modulation, which paves a new route to the integrated multifunctional all-fiber optoelectronic system. This article reviews the fast-progress field of hybrid 2D-materials-optical-fiber for the opto-electro-mechanical devices. The challenges and opportunities in this field for future development are discussed.

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Observation of surface morphology by reflection electron holography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154652 ◽

1989 ◽

Vol 47 ◽

pp. 536-537

Author(s):

N. Osakabe ◽

J. Endo ◽

T. Matsuda ◽

A. Tonomura

Keyword(s):

Phase Shift ◽

Surface Morphology ◽

High Sensitivity ◽

High Energy ◽

Path Difference ◽

Transmission Mode ◽

Electron Holography ◽

Dynamical Process ◽

High Vertical Resolution ◽

Amplification Technique

Progress in microscopy such as STM and TEM-TED has revealed surface structures in atomic dimension. REM has been used for the observation of surface dynamical process and surface morphology. Recently developed reflection electron holography, which employes REM optics to measure the phase shift of reflected electron, has been proved to be effective for the observation of surface morphology in high vertical resolution ≃ 0.01 Å.The key to the high sensitivity of the method is best shown by comparing the phase shift generation by surface topography with that in transmission mode. Difference in refractive index between vacuum and material Vo/2E≃10-4 owes the phase shift in transmission mode as shownn Fig. 1( a). While geometrical path difference is created in reflection mode( Fig. 1(b) ), which is measured interferometrically using high energy electron beam of wavelength ≃0.01 Å. Together with the phase amplification technique , the vertivcal resolution is expected to be ≤0.01 Å in an ideal case.

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Supercontinuum Generation in Optical Fibers

10.1017/cbo9780511750465 ◽

2009 ◽

Cited By ~ 262

Keyword(s):

Optical Fibers ◽

Supercontinuum Generation

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THE INFLUENCE OF PATH-DIFFERENCE IN A DISPERSIVE MEDIUM ON TWO-BEAM INTERFERENCE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1967204 ◽

1967 ◽

Vol 28 (C2) ◽

pp. C2-17-C2-17

Author(s):

H. H. HOPKINS

Keyword(s):

Dispersive Medium ◽

Path Difference

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High-voltage monitoring by the fiber-optic recirculating measuring system

Izmeritel`naya Tekhnika ◽

10.32446/0368-1025it.2020-2-38-44 ◽

2020 ◽

pp. 38-44

Author(s):

A. V. Polyakov ◽

M. A. Ksenofontov

Keyword(s):

Optical Fibers ◽

High Voltage ◽

Optical Sensors ◽

Electromagnetic Interference ◽

Fiber Optic ◽

Electric Power Industry ◽

Measuring System ◽

Voltage Range ◽

External Electromagnetic Fields ◽

Optic Communication

Optical technologies for measuring electrical quantities attract great attention due to their unique properties and significant advantages over other technologies used in high-voltage electric power industry: the use of optical fibers ensures high stability of measuring equipment to electromagnetic interference and galvanic isolation of high-voltage sensors; external electromagnetic fields do not influence the data transmitted from optical sensors via fiber-optic communication lines; problems associated with ground loops are eliminated, there are no side electromagnetic radiation and crosstalk between the channels. The structure and operation principle of a quasi-distributed fiber-optic high-voltage monitoring system is presented. The sensitive element is a combination of a piezo-ceramic tube with an optical fiber wound around it. The device uses reverse transverse piezoelectric effect. The measurement principle is based on recording the change in the recirculation frequency under the applied voltage influence. When the measuring sections are arranged in ascending order of the measured effective voltages relative to the receiving-transmitting unit, a relative resolution of 0,3–0,45 % is achieved for the PZT-5H and 0,8–1,2 % for the PZT-4 in the voltage range 20–150 kV.

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