Abstract: A multi-wavelength surface plasmon laser that simultaneously emits surface plasmons having a large number of wavelengths and includes an active layer whose thickness changes with position, and a metal cavity whose length changes with position so that light of different wavelengths is emitted according to position. Surface plasmons are generated at the interface between a metal layer and a semiconductor layer in response to the light of different wavelengths. The surface plasmons having different wavelengths may be resonated in the metal cavity whose length changes with position and may be emitted to the outside.

Abstract: Provided are a speckle-based authentication apparatus, an authentication system that includes the speckle-based authentication apparatus, and an authentication method using the speckle-based authentication apparatus. The speckle-based authentication apparatus includes an optical source configured to radiate light onto an object that is placed apart from the optical source; and a detector configured to detect a speckle pattern generated from the object in response to the light being radiated onto the object and detect location information of the object. Thus, the object is authenticated by comparing the speckle pattern detected by the detector with a speckle pattern stored in advance.

Abstract: According to an aspect of an exemplary embodiment, an authentication apparatus for authenticating an object includes an input coupler configured to receive incident light and generate surface plasmons from the incident light; and an output coupler configured to output a speckle pattern based on the surface plasmons.

Abstract: A multi-wavelength surface plasmon laser that simultaneously emits surface plasmons having a large number of wavelengths and includes an active layer whose thickness changes with position, and a metal cavity whose length changes with position so that light of different wavelengths is emitted according to position. Surface plasmons are generated at the interface between a metal layer and a semiconductor layer in response to the light of different wavelengths. The surface plasmons having different wavelengths may be resonated in the metal cavity whose length changes with position and may be emitted to the outside.

Abstract: Provided are nanostructures and optical devices having the nanostructures. The nanostructure may include a carbon nanomaterial layer, a nanopattern formed on the carbon nanomaterial layer, and a metal layer formed on a surface of the nanopattern. The nanostructure may be formed in a ring shape, and the metal layer may include a plurality of metal layers formed of different metals.

Abstract: An apparatus for outputting directional light includes a light-emitting structure including a light-emitting layer that emits light, and an optical antenna layer disposed on the light-emitting structure, wherein the optical antenna layer includes a light feeder configured to resonate light output from the light-emitting layer and a light reflector configure to reflect light output from the light feeder to have directivity. The light feeder and the light reflector are formed on a surface of the optical antenna layer.

Abstract: A surface plasmon polariton modulator capable of locally varying a physical property of a dielectric material to control a surface plasmon polariton. The surface plasmon polariton modulator includes a dielectric layer, including first and second dielectric portions, which is interposed between two metal layers. The second dielectric portion has a refractive index which varies with an electric field, a magnetic field, heat, a sound wave, or a chemical and/or biological operation applied thereto. The surface plasmon polariton modulator is configured to control one of an advancing direction, an intensity, a phase, or the like of a surface plasmon using an electric signal. The surface plasmon polariton modulator can operate as a surface plasmon polariton multiplexer or a surface plasmon polariton demultiplexer.

Abstract: A surface plasmon polariton modulator capable of locally varying a physical property of a dielectric material to control a surface plasmon polariton. The surface plasmon polariton modulator includes a dielectric layer, including first and second dielectric portions, which is interposed between two metal layers. The second dielectric portion has a refractive index which varies with an electric field, a magnetic field, heat, a sound wave, or a chemical and/or biological operation applied thereto. The surface plasmon polariton modulator is configured to control one of an advancing direction, an intensity, a phase, or the like of a surface plasmon using an electric signal. The surface plasmon polariton modulator can operate as a surface plasmon polariton multiplexer or a surface plasmon polariton demultiplexer.

Abstract: A surface plasmon polariton modulator capable of locally varying a physical property of a dielectric material to control a surface plasmon polariton. The surface plasmon polariton modulator includes a dielectric layer, including first and second dielectric portions, which is interposed between two metal layers. The second dielectric portion has a refractive index which varies with an electric field, a magnetic field, heat, a sound wave, or a chemical and/or biological operation applied thereto. The surface plasmon polariton modulator is configured to control one of an advancing direction, an intensity, a phase, or the like of a surface plasmon using an electric signal. The surface plasmon polariton modulator can operate as a surface plasmon polariton multiplexer or a surface plasmon polariton demultiplexer.