Recent progress in quantum nanophotonics brings novel ways for manipulating single photons in various nano-waveguides. Among them, one promising approach is to use optical nanofibres (ONFs), tapered optical fibres with sub-wavelength diameter waists. Here, we develop a hybrid system of an ONF and a single quantum dot (QD) operated at cryogenic temperatures.
View Article and Find Full Text PDFWe present a protocol for fabricating 1-D Photonic Crystal (PhC) cavities on subwavelength-diameter tapered optical fibers, optical nanofibers, using femtosecond laser-induced ablation. We show that thousands of periodic nano-craters are fabricated on an optical nanofiber by irradiating with just a single femtosecond laser pulse. For a typical sample, periodic nano-craters with a period of 350 nm and with diameter gradually varying from 50 - 250 nm over a length of 1 mm are fabricated on a nanofiber with diameter around 450 - 550 nm.
View Article and Find Full Text PDFWe demonstrate a method for making precise measurements of the diameter of a tapered optical fiber with a sub-wavelength diameter waist (an optical nanofiber). The essence of the method is to create a composite photonic crystal cavity by mounting a defect-mode grating on an optical nanofiber. The resultant cavity has a resonance wavelength that is sensitive to the nanofiber's diameter, allowing the diameter to be inferred from optical measurements.
View Article and Find Full Text PDFWe demonstrate cavity QED conditions in the Purcell regime for single quantum emitters on the surface of an optical nanofiber. The cavity is formed by combining an optical nanofiber and a nanofabricated grating to create a composite photonic crystal cavity. By using this technique, significant enhancement of the spontaneous emission rate into the nanofiber guided modes is observed for single quantum dots.
View Article and Find Full Text PDFWe implemented a photonic crystal nanofiber device by reversibly combining an optical nanofiber and a nanofabricated grating. Using the finite-difference time-domain method, we designed the system for minimal optical loss while tailoring the resonant wavelength and bandwidth of the device. Experimentally, we demonstrated that the combined system shows a strong photonic stop band in good agreement with numerical predictions.
View Article and Find Full Text PDF