Search

We report on the numerical design optimization of a new kind of relatively simple porous-core photonic crystal fiber (PCF) for terahertz (THz) waveguiding. A novel twist is introduced in the regular hexagonal PCF by including a diamond-shaped porous-core inside the hexagonal cladding. The numerical results obtained from an efficient finite-element method, which confirms a high birefringence of the order 10^\mathrm -2 and low effective material loss of 0.07 cm ^\mathrm -1 at 0.7-THz operating frequency. The proposed PCF is anticipated to be useful in polarization sensitive THz appliances. [ABSTRACT FROM PUBLISHER]

We report on a polymer-based porous-core photonic crystal fiber for simultaneous high-birefringent and low-loss propagation of narrowband terahertz (THz) electromagnetic waves. The high birefringence is induced by using rotated elliptical air holes inside the porous-core. The fiber is numerically analyzed with an efficient finite-element method. The simulation results exhibit an extremely high birefringence of ~0.042 and a very low effective material loss of ~0.07 cm-1 at an operating frequency of 1 THz. Moreover, we have found an optimal rotation angle (θ) = n30 deg (n is an odd integer). Other modal features of the fiber, such as confinement loss, power fraction, effective area, bending loss, and dispersion, also have been analyzed. We anticipate that the proposed fiber would be suitable in polarization maintaining THz wave guidance applications. [ABSTRACT FROM AUTHOR]

A novel (to the best of our knowledge) kind of porous-core spiral photonic crystal fiber (PCF) is proposed in this letter. It illustrates a tradeoff managed between material absorption and bending loss for efficient guidance of terahertz (THz) waves using a circular lattice array of smaller air-holes inside the core of an equiangular spiral structure. With maximum porosity and operating frequency of 1 THz, bending loss of 4.16 \times 10^\mathrm -16 cm ^-1 and effective material loss of 0.1 cm ^-1 are reported. In addition, other modal characteristics, such as effective area, confinement loss, and fabrication techniques of the proposed fiber have been discussed. The proposed THz waveguide can be potentially used for efficient and convenient transmission of THz waves. [ABSTRACT FROM PUBLISHER]

We present a thorough numerical analysis of a highly birefringent slotted porous-core circular photonic crystal fiber (PCF) for terahertz (THz) wave guidance. The slot shaped air-holes break the symmetry of the porous-core which offers a very high birefringence whereas the compact geometry of the circular cladding confines most of the power in the fiber-core. The fiber structure reported in this letter exhibits simultaneously ultrahigh modal birefringence of 7.5 \times 10^-2 and a very low effective absorption loss of 0.07 cm ^-1 for $y$ -polarization mode at an operating frequency of 1 THz. It is highly anticipated that the slotted-core waveguide would be of very much convenience in many polarization maintaining THz appliances. [ABSTRACT FROM PUBLISHER]

A porous-core circular photonic crystal fiber is designed for low-loss terahertz (THz) wave propagation. The circular arrangement of air holes, both in the periodic cladding and the porous core, makes it possible to guide most of the optical power through low-loss air, which is confirmed by the rigorous analysis of modal properties of the fiber while maintaining the single-mode propagation condition. The simulation results, found by using an efficient finite element method, show that a flattened dispersion of ±0.09 ps/THz/cm within 0.9 to 1.3 THz and an ultra-low material loss of 0.053 cm-1 at f = 1 THz is obtained for the reported design at optimal parameters. This kind of structure can be fabricated using capillary stacking or a sol-gel technique and is expected to be useful for wideband imaging and telecom applications. [ABSTRACT FROM AUTHOR]

We propose a porous-core octagonal photonic crystal fiber for low-loss terahertz (THz) waveguiding. Great attention is given to the geometries of the fiber inside the core to increase the fraction of power transmitted through the air holes. At an operating frequency f = 1 THz, this design exhibits a low effective material loss which is approximately 0.05 cm-1 or 0.2 dB/cm. In addition to the confinement loss, some other properties like the power fraction of the core air holes, responses of the effective material loss, and power fraction with respect to frequency have been also reported. This design is useful for efficient transmission of broadband terahertz radiation. [ABSTRACT FROM AUTHOR]