We demonstrate a spectrally correlated photon-pair source at telecom wavelengths (spanning across the S-, C-, and L-bands), based on type-0 spontaneous parametric downconversion (SPDC) in a fiber-coupled Zn-indiffused MgO doped periodically poled lithium niobate (PPLN) ridge waveguide. Modal analysis of the waveguide performed through numerical finite element method (FEM) simulation indicates that device temperature can be used to dramatically vary and control the emission spectrum. Efficient photon-pair generation is measured over a broad wavelength range from ∼1520 - 1580 nm [full width at half maximum (FWHM) > 45 nm] with a coincidence-to-accidental ratio (CAR) as high as ∼668 and spectral brightness ∼2.5 × 10 pairs/s/mW/nm. Such sources can be employed in wavelength division multiplexed (WDM) quantum key distribution (QKD) over existing fiber-optic networks.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1364/OL.472045 | DOI Listing |
The study, reliable generation, and application of spectral and polarization-correlated biphotons is a widely researched area in the field of quantum technology. In this Letter, we report a bright narrowband source of spectral and polarization-correlated orthogonal photon-pairs around the telecom wavelength of 1560 nm from a fiber-pigtailed, type-II quasi-phase-matched, MgO-doped periodically poled lithium niobate (MgO:ppLN) ridge waveguide. We achieved a high spectral brightness of ∼5×10 photon pairs/s/mW/nm with a coincidence-to-accidental ratio (CAR) value of ∼427 and an emission bandwidth of ∼2.
View Article and Find Full Text PDFWe demonstrate a spectrally correlated photon-pair source at telecom wavelengths (spanning across the S-, C-, and L-bands), based on type-0 spontaneous parametric downconversion (SPDC) in a fiber-coupled Zn-indiffused MgO doped periodically poled lithium niobate (PPLN) ridge waveguide. Modal analysis of the waveguide performed through numerical finite element method (FEM) simulation indicates that device temperature can be used to dramatically vary and control the emission spectrum. Efficient photon-pair generation is measured over a broad wavelength range from ∼1520 - 1580 nm [full width at half maximum (FWHM) > 45 nm] with a coincidence-to-accidental ratio (CAR) as high as ∼668 and spectral brightness ∼2.
View Article and Find Full Text PDFWe demonstrate terahertz (THz) wave generation by wavelength conversion in a ridge-type/bulk periodically poled lithium niobate (RT-/bulk-PPLN) under almost the same experimental conditions. When using the RT-PPLN, the ridge structure works as a slab waveguide for the incident pump beam (wavelength: ∼1 μm), and the generated THz wave (∼200 μm) was emitted uniformly from the entire side surface of the crystal. The RT-PPLN has a much higher conversion efficiency from the pumping beam to the THz wave than the bulk-PPLN, and the ratio improved several ten times compared with those of previous studies.
View Article and Find Full Text PDFNonlinear crystalline ridge waveguides, e.g., lithium niobate-on-insulator ridge waveguides, feature high index contrast and strong optical confinement, thus dramatically enhancing nonlinear interaction and facilitating various nonlinear effects.
View Article and Find Full Text PDFThe power scaling of continuous-wave (CW) second harmonic generation (SHG) in a MgO:periodically poled lithium niobite (PPLN) ridge waveguide is investigated. The nonlinear coefficient and propagation loss factors of the MgO:PPLN waveguide are verified for future reference. The MgO:PPLN waveguide structure is determined according to a practical fiber coupling configuration, as well as the theoretical model of output power characteristics.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!