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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

Effect of calcite dispersion on cloaking calculated by ray tracing.(a) The deviation angles of the beams with TM polarization reflected by the cloak with the design parameters indicated in Figure 1c. (b) Same as a, but for a slightly modified cloak geometry so that perfect cloaking occurs at wavelength of 532 nm, consistent with the experimental observations for the green laser beam. (c) The effect of dispersion for TE polarization in terms of the variation of reflection angles relative to those at λ=590 nm. In all the figures, the incident angle was set to 64.5°.
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f5: Effect of calcite dispersion on cloaking calculated by ray tracing.(a) The deviation angles of the beams with TM polarization reflected by the cloak with the design parameters indicated in Figure 1c. (b) Same as a, but for a slightly modified cloak geometry so that perfect cloaking occurs at wavelength of 532 nm, consistent with the experimental observations for the green laser beam. (c) The effect of dispersion for TE polarization in terms of the variation of reflection angles relative to those at λ=590 nm. In all the figures, the incident angle was set to 64.5°.

Mentions: The dispersion of calcite has a slight effect on the cloaking performance, which was shown by the measurement with red laser beam in Figure 3h and the rainbow edge effect in Figure 4c. A ray tracing calculation was carried out to quantitatively analyse the influence of calcite dispersion on the cloaking performance. A beam with TM polarization, once reflected by the cloak, is generally split into two except at the wavelength where the cloaking condition is rigorously satisfied. The two reflected beams deviate from that reflected by a horizontal flat mirror by an angle of φ1 and φ2, respectively, and the angle formed by the two beams is φ1–φ2. Figure 5a shows the ray tracing results for a cloak with the design parameters indicated in Figure 1c and an incident angle θ=64.5°. The cloak works perfectly at the design wavelength close to 590 nm, which is confirmed by the ray-tracing calculation. The deviation angles φ1, φ2 of the reflected beams are <1° across the visible range from 400 to 700 nm.


Macroscopic invisibility cloaking of visible light.

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

Effect of calcite dispersion on cloaking calculated by ray tracing.(a) The deviation angles of the beams with TM polarization reflected by the cloak with the design parameters indicated in Figure 1c. (b) Same as a, but for a slightly modified cloak geometry so that perfect cloaking occurs at wavelength of 532 nm, consistent with the experimental observations for the green laser beam. (c) The effect of dispersion for TE polarization in terms of the variation of reflection angles relative to those at λ=590 nm. In all the figures, the incident angle was set to 64.5°.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

f5: Effect of calcite dispersion on cloaking calculated by ray tracing.(a) The deviation angles of the beams with TM polarization reflected by the cloak with the design parameters indicated in Figure 1c. (b) Same as a, but for a slightly modified cloak geometry so that perfect cloaking occurs at wavelength of 532 nm, consistent with the experimental observations for the green laser beam. (c) The effect of dispersion for TE polarization in terms of the variation of reflection angles relative to those at λ=590 nm. In all the figures, the incident angle was set to 64.5°.
Mentions: The dispersion of calcite has a slight effect on the cloaking performance, which was shown by the measurement with red laser beam in Figure 3h and the rainbow edge effect in Figure 4c. A ray tracing calculation was carried out to quantitatively analyse the influence of calcite dispersion on the cloaking performance. A beam with TM polarization, once reflected by the cloak, is generally split into two except at the wavelength where the cloaking condition is rigorously satisfied. The two reflected beams deviate from that reflected by a horizontal flat mirror by an angle of φ1 and φ2, respectively, and the angle formed by the two beams is φ1–φ2. Figure 5a shows the ray tracing results for a cloak with the design parameters indicated in Figure 1c and an incident angle θ=64.5°. The cloak works perfectly at the design wavelength close to 590 nm, which is confirmed by the ray-tracing calculation. The deviation angles φ1, φ2 of the reflected beams are <1° across the visible range from 400 to 700 nm.

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