Abstract: An optical data storage and retrieval system that includes a phase change storage medium and dual energy sources. The phase change material may store information by undergoing a transformation from one structural state to another structural state through application of energy. The system is equipped with two energy sources, neither of which alone provides sufficient energy to effect the transformation. The combination of both energy sources, however, provides sufficient energy to induce the transformation needed to record information. The energy from either source may be optical, thermal, electromagnetic, mechanical or magnetic energy.

Abstract: A light-plasmon coupling lens including an optically transparent substrate having a light incident surface and a light-plasmon coupling surface opposite the light incident surface. The light-plasmon coupling surface including at least a set of circular concentric peaks/valleys which form a Fourier sinusoidal pattern in the radial direction of the circular concentric peaks/valleys. A conformal layer of metal is deposited on the light-plasmon coupling surface of the substrate and has aperture at the center of thereof through which plasmons are transmitted. An optical recording medium including a light-plasmon coupling lens.

Abstract: An optical data storage and retrieval system that includes a phase change storage medium and dual energy sources. The phase change material may store information by undergoing a transformation from one structural state to another structural state through application of energy. The system is equipped with two energy sources, neither of which alone provides sufficient energy to effect the transformation. The combination of both energy sources, however, provides sufficient energy to induce the transformation needed to record information. The energy from either source may be optical, thermal, electromagnetic, mechanical or magnetic energy.

Abstract: A light-plasmon coupling lens including an optically transparent substrate having a light incident surface and a light-plasmon coupling surface opposite the light incident surface. The light-plasmon coupling surface including at least a set of circular concentric peaks/valleys which form a Fourier sinusoidal pattern in the radial direction of the circular concentric peaks/valleys. A conformal layer of metal is deposited on the light-plasmon coupling surface of the substrate and has aperture at the center of thereof through which plasmons are transmitted. An optical recording medium including a light-plasmon coupling lens.

Abstract: An optical recording medium includes a crystallizing layer for enhancing the crystallization of a phase change memory layer, an energy storage layer for aiding the state transformations of a phase change memory layer, and/or a modifying element for increasing absorption and contrast at short wavelengths. An optical data storage and retrieval system containing same. Also a light-plasmon coupling lens including an optically transparent substrate having a light incident surface and a light-plasmon coupling surface opposite the light incident surface. The light-plasmon coupling surface including at least a set of circular concentric peaks/valleys which form a Fourier sinusoidal pattern in the radial direction of the circular concentric peaks/valleys. A conformal layer of metal is deposited on the light-plasmon coupling surface of the substrate and has aperture at the center of thereof through which plasmons are transmitted.

Abstract: Methods of writing information to an optical memory device. The methods comprise the step of writing a mark to the active material of the optical memory device by irradiating the material with an applied energy source. In one embodiment, the applied energy source provides a plurality of energy pulses. In another embodiment, energy in excess of that required to form a mark is released and dissipated in a manner that minimizes mark enlargement, spurious mark formation, recrystallization and back crystallization. The methods are effective to provide better cooling characteristics through enhancement of the capacitive cooling contribution.

Abstract: An element for steering electromagnetic beams. The element includes a phase change material in combination with dielectric and other layers in a multilayer optical stack. The phase change material that is reversibly transformable between two or more structural states, where different structural states differ with respect to refractive index and/or extinction coefficient. The structural state of the phase change material establishes a phase angle state for the element that dictates the direction of propagation of an output beam produced from an incident electromagnetic beam. Depending on the structural state, the element adopts one of two principal phase angle states and a binary beam steering capability is achieved in which an incident electromagnetic beam can be redirected in either of two directions. In a preferred embodiment, the output beam is a reflected beam and the element includes a phase change material sandwiched between two dielectric materials and supported by a metal layer.

Abstract: An element for reflecting, transmitting, focusing, defocusing or wavefront correction of electromagnetic radiation in the terahertz frequency range. The elements include a grid of conductive strips including active regions comprising a chalcogenide phase change material. The chalcogenide material can be in an amorphous, crystalline or partially crystalline state. The dispersive characteristics of the grid (e.g. impedance, admittance, capacitance, inductance) influence one or more of the reflection, transmission, state of focusing or wavefront characteristics of incident electromagnetic radiation through the action of a stored phase taper formed by establishing a crystallinity gradient over a series of active chalcogenide regions or domains in one or more directions of the element.

Abstract: A photonic crystal having reversibly tunable photonic properties. The photonic crystal includes a phase change material having a plurality of structural states that vary with respect to fractional crystallinity. Optical constants including refractive index, extinction coefficient and permittivity vary as the fractional crystallinity of the phase change material is varied thereby providing tunability of photonic crystal properties. Variations among the structural states of the phase change material are reversibly effected through the addition of energy in forms including optical or electrical energy. The photonic crystals may include defects that provide photonic states within the photonic band gap. The position of these states is tunable through the control of the fractional crystallinity of the phase change material included in the photonic crystal. Electromagnetic radiation resonators including photonic crystals having photonic states in the photonic band gap are further provided.

Abstract: An element for steering electromagnetic beams. The element includes a phase change material in combination with dielectric and other layers in a multilayer optical stack. The phase change material that is reversibly transformable between two or more structural states, where different structural states differ with respect to refractive index and/or extinction coefficient. The structural state of the phase change material establishes a phase angle state for the element that dictates the direction of propagation of an output beam produced from an incident electromagnetic beam. Depending on the structural state, the element adopts one of two principal phase angle states and a binary beam steering capability is achieved in which an incident electromagnetic beam can be redirected in either of two directions. In a preferred embodiment, the output beam is a reflected beam and the element includes a phase change material sandwiched between two dielectric materials and supported by a metal layer.

Abstract: A reconfigurable and stationary element for the engineering of the wavefront of electromagnetic radiation. The element includes a phase change material that may be reversibly transformed between its crystalline and amorphous states. By forming a gradient in crystallinity, a phase taper may be stored in the phase change material of the instant element. The phase taper provides control of the phase angle of reflected or reradiated electromagnetic radiation. An incident wavefront of electromagnetic radiation interacts with the instant element and is reradiated with controlled propagation characteristics imposed by the stored phase taper. The instant element may provide non-specular reflection, beam steering, focusing, defocusing, symmetrical and asymmetrical cross section effects, and wavefront correction. In a preferred embodiment, a pattern of amorphous marks is formed within a crystalline matrix of phase change material.

Abstract: An element for reflecting, transmitting, focusing, defocusing or wavefront correction of electromagnetic radiation in the terahertz frequency range. The elements include a grid of conductive strips including active regions comprising a chalcogenide phase change material. The chalcogenide material can be in an amorphous, crystalline or partially crystalline state. The dispersive characteristics of the grid (e.g. impedance, admittance, capacitance, inductance) influence one or more of the reflection, transmission, state of focusing or wavefront characteristics of incident electromagnetic radiation through the action of a stored phase taper formed by establishing a crystallinity gradient over a series of active chalcogenide regions or domains in one or more directions of the element.

Abstract: A reconfigurable and stationary element for the engineering of the wavefront of electromagnetic radiation. The element includes a phase change material that may be reversibly transformed between its crystalline and amorphous states. By forming a gradient in crystallinity, a phase taper may be stored in the phase change material of the instant element. The phase taper provides control of the phase angle of reflected or reradiated electromagnetic radiation. An incident wavefront of electromagnetic radiation interacts with the instant element and is reradiated with controlled propagation characteristics imposed by the stored phase taper. The instant element may provide non-specular reflection, beam steering, focusing, defocusing, symmetrical and asymmetrical cross section effects, and wavefront correction. In a preferred embodiment, a pattern of amorphous marks is formed within a crystalline matrix of phase change material.

Abstract: A photonic crystal having reversibly tunable photonic properties. The photonic crystal includes a phase change material having a plurality of structural states that vary with respect to fractional crystallinity. Optical constants including refractive index, extinction coefficient and permittivity vary as the fractional crystallinity of the phase change material is varied thereby providing tunability of photonic crystal properties. Variations among the structural states of the phase change material are reversibly effected through the addition of energy in forms including optical or electrical energy. The photonic crystals may include defects that provide photonic states within the photonic band gap. The position of these states is tunable through the control of the fractional crystallinity of the phase change material included in the photonic crystal. Electromagnetic radiation resonators including photonic crystals having photonic states in the photonic band gap are further provided.

Abstract: An optical recording medium includes a crystallizing layer for enhancing the crystallization of a phase change memory layer, an energy storage layer for aiding the state transformations of a phase change memory layer, and/or a modifying element for increasing absorption and contrast at short wavelengths. An optical data storage and retrieval system containing same. Also a light-plasmon coupling lens including an optically transparent substrate having a light incident surface and a light-plasmon coupling surface opposite the light incident surface. The light-plasmon coupling surface including at least a set of circular concentric peaks/valleys which form a Fourier sinusoidal pattern in the radial direction of the circular concentric peaks/valleys. A conformal layer of metal is deposited on the light-plasmon coupling surface of the substrate and has aperture at the center of thereof through which plasmons are transmitted.