摘要:
A device is provided for generating a photonic signal having a phase different from an input photonic signal that is incident on the device. The input photonic signal has an signal frequency, signal bandwidth, and a signal intensity. The device comprises a plurality of material layers. The material layers are arranged such that the device exhibits a photonic band gap structure. The photonic band gap structure exhibits a transmission band edge that corresponds to the input photonic signal frequency. A second photonic signal is generated at a second photonic frequency preferably close to a second band edge. The interaction of the input photonic signal with the second photonic signal generates a phase shift of order &pgr; for relatively small input intensities.
摘要:
Non-linear reflectivity and non-linear transmissivity of a first photonic signal incident on a photonic band gap (PBG) structure are controlled by applying a second photonic signal to the PBG structure while the first photonic signal is incident on the PBG structure. The first and second photonic signals have respective frequencies near a low frequency, first order band gap edge and a high frequency, second order band gap edge resonance peak of the PBG structure. The first photonic signal undergoes enhanced non-linear gain near the band gap edges when a predetermined phase difference is imposed between the first and second photonic signals, resulting in dramatic reflectivity and transmissivity changes for a band gap structure of only a few microns in length.
摘要:
We have shown that a single layer of a 3D Zero Index Material (ZIM) has omnidirectional reflection properties. In the range between the electric plasma frequency and the magnetic plasma frequency, ZIM reflect radiation for all angles of incidence and polarization with reflectivities of ˜99%. In addition, with increasing angles of incidence, the reflecting band does not shift in frequency but actually widens. The operational bandwidth can be 100% or greater by increasing the separation between the electric and magnetic plasma frequencies. We have also shown that in the spectral region that allows the omnidirectional gap, ZIM can be used as the cladding of hollow waveguides with better performance than traditional hollow waveguides.
摘要:
A photonic band gap (PBG) device is provided for frequency up and/or down-converting first and second photonic signals incident on the device to produce a down-converted output photonic signal. When the first and second incident photonic signals have respective first and second frequencies ω3 and ω2, the down-converted photonic signal has a third frequency ω1=ω3−ω2. When the first incident field has a frequency ω1, the first up-converted photonic signal has a second frequency ω3=ω1+ω2. The second up-converted photonic signal has a third frequency ω3=ω1+ω2. Thus, the PBG device can be used to generate coherent near- and mid-IR signals by frequency down-converting photonic signals from readily available photonic signal sources, or red, blue, and ultraviolet signals by up-converting the same readily available photonic signal sources. The PBG device includes a layered stack having a plurality of first material layers and a plurality of second material layers. The first and second material layers are arranged such that the PBG device exhibits a photonic band gap structure exhibiting first, second and third transmission band edges respectively corresponding to the first, second, and third frequencies. An interaction of the first and second photonic signals with the arrangement of layers in the metal stack causes a mixing process to generate the both up and down-converted photonic signal at the third frequency.
摘要:
A waveguide has upper and lower cladding regions. A core of the waveguide made of a non-linear optical polymer is positioned between the upper and lower cladding regions. A first electrode is connected to the upper cladding region and a second electrode is connected to the lower cladding region. The upper cladding region and the lower cladding region are made of photonic band gap materials and have multiple periods of cladding layers with each period having a first layer having a linear refractive index of n1 and each period having a second layer having a linear refractive index of n2. The waveguide allows for minimal distances to exist between the electrodes while allowing for virtual lossless cm-long transmission of propagating light. By applying a voltage to the electrodes, the propagated light can be modulated.
摘要:
A device and method of optics propagation and signal control integrated with micro-electro-mechanical-switches (MEMS). This device modifies optical transmission properties of a transparent multilayer metal stack by mechanically varying the thickness of an air gap between layers in the stack This is accomplished by utilizing MEMS coupled with the stack to change the optical path in a given layer of the transparent multilayer metal stack. This can be accomplished by developing a hybrid combination of transparent multilayer stacks and MEMS, wherein an air gap is used as one of the dielectric layers. The air gap thickness can be controlled by the MEMS device thereby enabling dramatic control of the optical path.
摘要:
An LCD device for displaying an image includes pixel control electrodes constructed as a transparent metal stack having a photonic band gap (PBG) structure that transmits a visible range of wavelengths and suppresses a non-visible range of wavelengths. A liquid crystal layer between the pixel control electrodes controls the transmission of light in response to a voltage applied across the pixel control electrodes. A light emitting structure (LES), such as a light emitting diode (LED) or light emitting polymer (LEP) device includes a cathode electrode, a substrate, an active layer for emitting visible light, and a transparent anode electrode having a PBG structure.