Ferrocell or Ferrolens is a type of superparamagnetic optical device which can display magnetostatic or dynamic magnetic fields in real time and in color. In other words, it is a quantum optical magnetic flux viewer. 
For its operation it is using a thin film of ferrofluid encapsulated inside a lens similar to a Hele-Shaw cell filled with ferrofluid. Usually the ferrocell is fitted with a LED strip light programmable source on its periphery emulating different lighting conditions. The superparamagnetic nanoparticles inside the ferrofluid are following the magnetic flux of an external field induced into the ferrocell (i.e. a permanent magnet placed on top or under the ferrocell). At the same time, the oriented and aligned with the magnetic field lines nanoparticles, are emitting back part of their incident light (Video) thus essentially allowing them to "paint" the magnetic field lines and therefore making them visible. Light intensity and color texture of the field lines shown can vary slightly accordingly to magnetic field strength and direction.
A ferrocell has advanced visualization capabilities in detail, spatial resolution, sensitivity, color information and can depict also depth of field information on an observed magnetic field essentially making it a 3D holographic nanomagnetic direct observation passive device for magnetic fields and related quantum effects. Also when the ferrocell is used with a LED light strip, it shows the wire-frame model of the individual magnetic flux lines of a static magnetic field.
Currently, it is the only device, reported by academia of this type which can efficiently visualize fast changing (i.e. dynamic) magnetic fields and its superparamagnetic properties is allowing it to display the Quantum Field of Magnets (QFM).
Further academic research is also carried out for these type of devices for the polarization of light using magnetic fields.
Ferrocells are available today mainly for research applications and education in general, under the registered trademark Ferrocell as a patented product. Many Youtube videos are available with “do-it-yourself” instructions for making ferrocells for personal use. Video
References[edit | edit source]
- Markoulakis, Emmanouil; Konstantaras, Antonios; Antonidakis, Emmanuel (2018). "The quantum field of a magnet shown by a nanomagnetic ferrolens". Journal of Magnetism and Magnetic Materials. 466: 252–259. arXiv: . doi:10.1016/j.jmmm.2018.07.012. ISSN 0304-8853.
- Michael Snyder and Johnathan Frederick (June 18, 2008). "Photonic Dipole Contours of a Ferrofluid Hele-Shaw Cell". Chrysalis: The Murray State University Journal of Undergraduate Research.
- Tufaile, Alberto; Vanderelli, Timm A.; Tufaile, Adriana Pedrosa Biscaia (2017). "Light Polarization Using Ferrofluids and Magnetic Fields". Advances in Condensed Matter Physics. 2017: 1–7. doi:10.1155/2017/2583717. ISSN 1687-8108.
- Markoulakis, Emmanouil; Rigakis, Iraklis; Chatzakis, John; Konstantaras, Antonios; Antonidakis, Emmanuel (2018). "Real time visualization of dynamic magnetic fields with a nanomagnetic ferrolens". Journal of Magnetism and Magnetic Materials. 451: 741–748. arXiv: . Bibcode:2018JMMM..451..741M. doi:10.1016/j.jmmm.2017.12.023.
- Magnetic flux viewer, 2007-04-12, retrieved 2018-04-29
- Wen, C.-Y.; Su, W.-P. (March 2005). "Natural convection of magnetic fluid in a rectangular Hele-Shaw cell". Journal of Magnetism and Magnetic Materials. 289: 299–302. doi:10.1016/j.jmmm.2004.11.085. ISSN 0304-8853.
- Rablau, Corneliu; Vaishnava, Prem; Sudakar, Chandran; Tackett, Ronald; Lawes, Gavin; Naik, Ratna (2008-11-06). "Magnetic-field-induced optical anisotropy in ferrofluids: A time-dependent light-scattering investigation". Physical Review E. 78 (5): 051502. doi:10.1103/PhysRevE.78.051502.
- "FERROCELL.US". ferrocell.us. Retrieved 2018-04-29.
- "FERROCELL Trademark of Timm A. Vanderelli - Registration Number 4813718 - Serial Number 86185455 :: Justia Trademarks". trademarks.justia.com. Retrieved 2018-04-29.