Ultra-sensitive DNA detection with single-base mismatch resolution using a tapered thin-diameter photonic crystal fiber interferometer.

A tapered thin-diameter photonic crystal fiber interferometer (TTD-PCFI) biosensor is proposed and demonstrated for DNA hybridization detection with an ultra-low limit of detection (LoD) and high specificity. The TTD-PCFI is fabricated by arc-discharged melting and adiabatic tapering, with a lower loss and stronger evanescent optical field. The fabricated TTD-PCFI with a diameter of 8.

Label-free, ultra-low detection limit DNA biosensor using high quality optical microcavity functionalized by DNA tetrahedral nanostructure probes.

This study proposes and demonstrates a novel label-free DNA biosensor using high quality optical microcavity functionalized by 3D DNA nanostructure probes. To achieve ultra-low limit DNA biosensing, optical sensing interface of the hollow-core, thin wall-thickness microcavity was functionalized by self-assembled DNA tetrahedral nanostructure (DTN) probes with size of 17 bp and length of ∼5.8 nm.

Highly sensitive RI and temperature sensor based on an asymmetric fiber coupler.

We propose and demonstrate a highly sensitive refractive index (RI) and temperature sensor based on an asymmetric fiber coupler (AFC). The AFC was fabricated by weak fusion of a pre-stretched single-mode fiber and a few-mode fiber. An ultra-sensitivity RI can be achieved near the dispersion turning point (DTP).

Broadband tunable single-longitudinal-mode erbium-doped fiber ring laser based on a microfiber knot resonator.

We propose and demonstrate a broadband tunable single-longitudinal-mode (SLM) erbium-doped fiber laser based on a microfiber knot resonator (MKR). The MKR is made from a double-ended fiber taper and employed for SLM filtering based on the Vernier effect. An unpumped erbium-doped fiber is used in the fiber laser cavity to suppress mode-hopping for a stabilized SLM laser operation.

Optofluidic microcapillary biosensor for label-free, low glucose concentration detection.

We demonstrate label-free detection of low glucose concentration based on whispery gallery mode resonance in an optofluidic microcapillary (OFMC) biosensor. The wall surface of the OFMC is bio-chemically functionalized to detect cellular-level glucose concentration as low as 2.78 mM.

Novel temperature-independent microfiber sensor fabricated with the tapering-twisting-tapering technique.

In this paper, a novel twist and refractive index microfiber sensor fabricated with the tapering-twisting-tapering technique has been proposed and demonstrated, for the first time to the best of our knowledge. Experimental results show that the interference intensity of the microfiber increases with the increment of pre-tapered length and the intervening twist number. The sensitivity of the microfiber sensor with respect to twist is found to be 2.

High efficiency mode-locked, cylindrical vector beam fiber laser based on a mode selective coupler.

We propose and demonstrate an all-fiber passively mode-locked laser with a figure-8 cavity, which generates pulsed cylindrical vector beam output based on a mode selective coupler (MSC). The MSC made of a two mode fiber and a standard single mode fiber is used as both the intracavity transverse mode converter and mode splitter with a low insertion loss of about 0.65 dB.

Focus modulation of cylindrical vector beams by using 1D photonic crystal lens with negative refraction effect.

Sub-wavelength focusing of cylindrical vector beams (CVBs) has attracted great attention due to the specific physical effects and the applications in many areas. More powerful, flexible and effective ways to modulate the focus transversally and also longitudinally are always being pursued. In this paper, cylindrically symmetric lens composed of negative-index one-dimensional photonic crystal is proposed to make a breakthrough.