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Macroscopic invisibility cloaking of visible light.

Chen X, Luo Y, Zhang J, Jiang K, Pendry JB, Zhang S - Nat Commun (2011)

Bottom Line: All the invisibility cloaks demonstrated thus far, however, have relied on nano- or micro-fabricated artificial composite materials with spatially varying electromagnetic properties, which limit the size of the cloaked region to a few wavelengths.The cloak operates at visible frequencies and is capable of hiding, for a specific light polarization, three-dimensional objects of the scale of centimetres and millimetres.Our work opens avenues for future applications with macroscopic cloaking devices.

View Article: PubMed Central - PubMed

Affiliation: School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, UK.

ABSTRACT
Invisibility cloaks, which used to be confined to the realm of fiction, have now been turned into a scientific reality thanks to the enabling theoretical tools of transformation optics and conformal mapping. Inspired by those theoretical works, the experimental realization of electromagnetic invisibility cloaks has been reported at various electromagnetic frequencies. All the invisibility cloaks demonstrated thus far, however, have relied on nano- or micro-fabricated artificial composite materials with spatially varying electromagnetic properties, which limit the size of the cloaked region to a few wavelengths. Here, we report the first realization of a macroscopic volumetric invisibility cloak constructed from natural birefringent crystals. The cloak operates at visible frequencies and is capable of hiding, for a specific light polarization, three-dimensional objects of the scale of centimetres and millimetres. Our work opens avenues for future applications with macroscopic cloaking devices.

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Related in: MedlinePlus

Ray tracing of light passing through the cloak system at 532 nm.The refractive index of the surrounding media is assumed to be 1.532. (a, b) Light incident on a cloaked bump at incident angles of (a) 45° and (b) 15°, showing almost no scattering. (c, d) Without cloaking, the bump strongly scatters the light into different directions. Although the cloak is designed at 590 nm, in accordance with the experiment, the ray-tracing calculation is performed at 532 nm.
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f2: Ray tracing of light passing through the cloak system at 532 nm.The refractive index of the surrounding media is assumed to be 1.532. (a, b) Light incident on a cloaked bump at incident angles of (a) 45° and (b) 15°, showing almost no scattering. (c, d) Without cloaking, the bump strongly scatters the light into different directions. Although the cloak is designed at 590 nm, in accordance with the experiment, the ray-tracing calculation is performed at 532 nm.

Mentions: A ray-tracing calculation was performed to verify the design described above. As shown in Figure 2a and b, beams with TM polarization incident at two different angles are both reflected without distortion, numerically verifying the cloaking design given by equations (6–8). On the other hand, for transverse electric (TE) polarization (which does not exhibit a cloaking effect), the light is reflected into different directions by the two bottom facets, leading to significant splitting, which can be observed in the far field (Fig. 2c,d).


Macroscopic invisibility cloaking of visible light.

Chen X, Luo Y, Zhang J, Jiang K, Pendry JB, Zhang S - Nat Commun (2011)

Ray tracing of light passing through the cloak system at 532 nm.The refractive index of the surrounding media is assumed to be 1.532. (a, b) Light incident on a cloaked bump at incident angles of (a) 45° and (b) 15°, showing almost no scattering. (c, d) Without cloaking, the bump strongly scatters the light into different directions. Although the cloak is designed at 590 nm, in accordance with the experiment, the ray-tracing calculation is performed at 532 nm.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3105339&req=5

f2: Ray tracing of light passing through the cloak system at 532 nm.The refractive index of the surrounding media is assumed to be 1.532. (a, b) Light incident on a cloaked bump at incident angles of (a) 45° and (b) 15°, showing almost no scattering. (c, d) Without cloaking, the bump strongly scatters the light into different directions. Although the cloak is designed at 590 nm, in accordance with the experiment, the ray-tracing calculation is performed at 532 nm.
Mentions: A ray-tracing calculation was performed to verify the design described above. As shown in Figure 2a and b, beams with TM polarization incident at two different angles are both reflected without distortion, numerically verifying the cloaking design given by equations (6–8). On the other hand, for transverse electric (TE) polarization (which does not exhibit a cloaking effect), the light is reflected into different directions by the two bottom facets, leading to significant splitting, which can be observed in the far field (Fig. 2c,d).

Bottom Line: All the invisibility cloaks demonstrated thus far, however, have relied on nano- or micro-fabricated artificial composite materials with spatially varying electromagnetic properties, which limit the size of the cloaked region to a few wavelengths.The cloak operates at visible frequencies and is capable of hiding, for a specific light polarization, three-dimensional objects of the scale of centimetres and millimetres.Our work opens avenues for future applications with macroscopic cloaking devices.

View Article: PubMed Central - PubMed

Affiliation: School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, UK.

ABSTRACT
Invisibility cloaks, which used to be confined to the realm of fiction, have now been turned into a scientific reality thanks to the enabling theoretical tools of transformation optics and conformal mapping. Inspired by those theoretical works, the experimental realization of electromagnetic invisibility cloaks has been reported at various electromagnetic frequencies. All the invisibility cloaks demonstrated thus far, however, have relied on nano- or micro-fabricated artificial composite materials with spatially varying electromagnetic properties, which limit the size of the cloaked region to a few wavelengths. Here, we report the first realization of a macroscopic volumetric invisibility cloak constructed from natural birefringent crystals. The cloak operates at visible frequencies and is capable of hiding, for a specific light polarization, three-dimensional objects of the scale of centimetres and millimetres. Our work opens avenues for future applications with macroscopic cloaking devices.

Show MeSH
Related in: MedlinePlus