Highly sensitive refractometer with a photonic-crystal-fiber long-period grating.
We present highly sensitive refractometers based on a long-period grating in a large-mode-area photonic crystal fiber (PCF). The maximum sensitivity is 1500 nm/refractive index unit at a refractive index of 1.33, to our knowledge the highest reported for any fiber grating. The minimal detectable index […]
Spectral-purity-enhancing layer for multilayer mirrors.
We demonstrate, both theoretically and experimentally, that special spectral-purity-enhancing multilayer mirror systems can be designed and fabricated to substantially reduce the level of out-of-band radiation expected in an extreme ultraviolet lithographic tool. A first proof of principle of applying such spectral-purity-enhancement layers showed reduced out-of-band reflectance by a […]
Random lasing in freely suspended dye-doped nematic liquid crystals.
Random lasing in fully disordered systems having organic and inorganic nature has been the subject of extensive studies since the beginning of the past decade. The interest mainly emerges from the unexpected role played by disorder in the laser action. The disorder was considered […]
Photonic generation of a microwave signal by incorporating a delay interferometer and a saturable absorber.
A novel approach to generate microwave signals is presented by employing a dual-wavelength erbium-doped fiber ring laser. By using a delay interferometer as a comb filter cascaded with a tunable bandpass filter and a saturable absorber formed by […]
Plasmonic electro-optic modulator design using a resonant metal grating.
A plasmonic electro-optic modulator design using an evanescently coupled resonant metal grating is numerically studied in this Letter. Owing to excitation and propagation of long-range surface plasmons between the metal grating nanowires, a deep and narrow reflection dip can be obtained. Improved modulation performance […]
Optofluidic variable aperture.
A variable aperture has been fabricated and demonstrated using polydimethylsiloxane-based optofluidic technology. The device consists of a deformable membrane, an air pressure chamber, a cavity filled with light-absorbing liquid, and a rigid transparent upper plate. The working principle of the device is based on the deformable capability of the thin […]
Near-infrared metamaterial films with reconfigurable transmissive/reflective properties.
A near-infrared metamaterial design that is reconfigurable between almost completely transmissive and reflective states is presented. The reconfiguration is enabled by tuning the anisotropic nematic liquid crystals used as a spacer layer between two silver nanoplates in a planar doubly periodic metamaterial. The design is optimized […]
Multiple-image hiding by information prechoosing.
The information inevitably lost in multiple-image hiding is discarded in advance by the operation of prechoosing information before the hiding process; thus both fidelity and multiplexing capacity can be improved significantly. Various characters of each image provide a great many possibilities for information prechoosing. The ideal low-pass filter […]
Femto-Newton light force measurement at the thermal noise limit.
The measurement of very small light forces has wide applications in many fields of physics. A common measurement method for small force detection is the determination of changes in the dynamic behavior of mechanical oscillators, either in amplitude or in frequency. The detection of […]
Miniaturized fiber inline Fabry-Perot interferometer fabricated with a femtosecond laser.
We report a miniaturized inline Fabry-Perot interferometer directly fabricated on a single-mode optical fiber with a femtosecond laser. The device had a loss of 16 dB and an interference visibility exceeding 14 dB. The device was tested and survived in high temperatures up […]
