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How Can Optical Engineers Use Weyl Semimetals?

Weyl semimetals possess many unusual electronic, thermal, and optical properties. For example, they exhibit surface Fermi arc states, chiral anomaly, unconventional charge and heat transport, strain-induced axial gauge fields, novel collective modes, unusual magneto-optical conductivity, and so on...

Majorization Theory for Unitary Control of Optical Absorption and Emission

Unitary control changes the absorption and emission of an object by transforming the external light modes. It is widely used and underlies coherent perfect absorption. We show that unitary control can achieve perfect violation or preservation of Kirchhoff's law in nonreciprocal objects, and uniform absorption or emission for any object using the mathematics of majorization...