Terahertz suspended core optical fiber

Abstract

The application provides a terahertz suspended core optical fiber, and belongs to the technical field of optical fibers, comprising an outer sleeve, a plurality of type I medium tubes and a plurality of type II medium tubes with the same number as the type I medium tubes; wherein the plurality of type I medium tubes are arranged in the outer sleeve, and each type I medium tube is tangent to the outer sleeve; the plurality of type II medium tubes are arranged in the outer sleeve, and one type II medium tube is arranged on the outer wall of each type I medium tube; based on the principle of modified total internal reflection, the dependence of a traditional suspended core optical fiber on a thin arm in structure is avoided; all the structural units are simple optical fiber structures with circular boundaries, which will have more prominent advantages in optical fiber manufacturing. The hollow porous structure can ensure that most of the energy in the mode is distributed in the air, and effectively reduces the absorption loss.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of optical fiber, in particular to a terahertz suspended core optical fiber. BACKGROUND

[0002] With the rapid development of optical communication technology, terahertz technology has been widely used in broadband communication, biomedical sensing, nondestructive testing, security sensitive applications and other fields. However, dielectric materials are easy to absorb terahertz waves, resulting in huge loss in practical application; reducing the inherent absorption of terahertz waves is one of the key factors to increase the transmission distance of terahertz waves, and low-loss terahertz waveguide is an important component required to provide transmission channel in terahertz system; one of the special advantages of suspended core optical fiber is that the optical fiber core can be isolated from external interference, which makes the suspended core optical fiber easy to be manually operated and supported by a support, so as to be free from the interference of the surrounding environment.

[0003] At present, the suspended core optical fiber disclosed in the prior art has the disadvantages of complex optical fiber structure, high preparation cost; on the other hand, the existing suspended core optical fiber has high loss and narrow dispersion range. SUMMARY

[0004] The present application aims to at least solve one of the problems in the prior art or related art.

[0005] To this end, the first aspect of the present application is to provide a terahertz suspended core optical fiber.

[0006] Therefore, according to the first aspect of the present application, a terahertz suspended core optical fiber is provided, comprising:

[0007] an outer sleeve tube;

[0008] a plurality of type I medium tubes, arranged in the outer sleeve tube, each type I medium tube being tangent to the outer sleeve tube;

[0009] a plurality of type II medium tubes, arranged in the outer sleeve tube, the number of type II medium tubes being the same as that of type I medium tubes, each type I medium tube being tangent to one type II medium tube on its outer wall;

[0010] wherein the radius of the type I medium tube is greater than the radius of the type II medium tube.

[0011] In a possible technical solution, further, there is no connection node between the plurality of type I medium tubes; there is no connection node between the plurality of type II medium tubes

[0012] In a possible technical solution, further, the tangent point between each type I medium tube and the outer sleeve tube is a first tangent point; the tangent point between each type I medium tube and the type II medium tube tangent thereto is a second tangent point;

[0013] The line between each first tangent point and the corresponding second tangent point passes through the center of the first type medium tube corresponding to the first tangent point.

[0014] In a possible technical solution, further, the area surrounded by the outer wall of the plurality of second type medium tubes is a first type hole, and the internal area of the second type medium tube is a second type hole; the area surrounded by the outer wall of the plurality of first type medium tubes, the outer wall of the plurality of second type medium tubes and the inner wall of the outer sleeve tube is a third type hole, and the internal area of the first type medium tube is a fourth type hole.

[0015] In a possible technical solution, further, the first type hole, the second type hole and the plurality of second type medium tubes constitute a core, the third type hole, the fourth type hole and the first type medium tube constitute a cladding, the effective refractive index of the core is greater than the effective refractive index of the cladding, and the optical principle is a modified total internal reflection effect.

[0016] In a possible technical solution, further, the first type hole, the second type hole, the third type hole and the fourth type hole are all filled with air.

[0017] In a possible technical solution, further, the thickness of the outer sleeve tube is greater than or equal to 0.2 mm, the thickness of the first type medium tube is 10 μm-100 μm, and the thickness of the second type medium tube is 10 μm-100 μm.

[0018] In a possible technical solution, further, the number of the first type medium tubes is 3, 4, 5 or 6.

[0019] In a possible technical solution, further, the material of the outer sleeve tube, the first type medium tube and the second type medium tube is any one of silica, soft glass or plastic.

[0020] In a possible technical solution, further, the outer sleeve tube, the first type medium tube and the second type medium tube are all circular tubes.

[0021] According to the first aspect of the present application, the working principle of the terahertz suspended core optical fiber is as follows:

[0022] The total internal reflection phenomenon describes that when light propagates from a high refractive index medium (core) to a low refractive index medium (cladding), it will be totally reflected without entering the cladding if the angle of incidence exceeds the critical angle. The modified total internal reflection principle is an extension of this phenomenon, in which the cladding may no longer be a uniform medium, but is composed of low refractive index microstructures (such as air holes). The interaction of these microstructures with the high refractive index core affects the propagation path of light, and the terahertz suspended core optical fiber according to the first aspect of the present application is based on this principle.

[0023] According to the terahertz suspended core optical fiber of the first aspect of the present application, the beneficial effects are as follows: the optical transmission principle of the terahertz suspended core optical fiber of the present application is based on the modified total internal reflection principle, avoiding the dependence on the thin arm in the manufacturing of the traditional suspended core optical fiber; this improvement has a positive impact on the optical fiber manufacturing process; such a structure can ensure that most of the energy in the mode is distributed in the air hole, effectively reducing the absorption loss; the optical fiber core is supported by the support, realizing effective isolation from the surrounding environment, reducing external interference, and improving the stability of the optical fiber. The optical fiber structure is simple, all the boundaries are circular, which not only facilitates manufacturing, but also enhances the anti-deformation ability of the optical fiber. The optical fiber has extremely low loss and wide and flat dispersion characteristics, ensuring high performance of the signal in long-distance transmission.

[0024] Additional aspects and advantages of the application will become apparent from the following description with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0025] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description, taken in conjunction with the following drawings in which:

[0026] Figure 1 The structural schematic diagram of the terahertz suspended core optical fiber according to the embodiment one and the embodiment two of the present application is shown;

[0027] Figure 2 The electric field field strength distribution schematic diagram of the terahertz suspended core optical fiber according to the embodiment one of the present application is shown;

[0028] Figure 3 The confinement loss and absorption loss curve diagram of the terahertz suspended core optical fiber according to the embodiment one of the present application is shown;

[0029] Figure 4 The dispersion curve diagram of the terahertz suspended core optical fiber according to the embodiment one of the present application is shown;

[0030] Figure 5 The total loss curve diagram of the terahertz suspended core optical fiber according to the embodiment two of the present application is shown;

[0031] Figure 6 The dispersion curve diagram of the terahertz suspended core optical fiber according to the embodiment two of the present application is shown;

[0032] Figure 7 The structural schematic diagram of the terahertz suspended core optical fiber according to the embodiment three of the present application is shown;

[0033] Figure 8 The structural schematic diagram of the terahertz suspended core optical fiber according to the embodiment four of the present application is shown;

[0034] Figure 9 A structural schematic diagram of a terahertz suspended core optical fiber according to Embodiment Five of the present application is shown.

[0035] wherein, Figures 1 to 9 The correspondence between the reference signs and the component names is as follows:

[0036] 1, outer sleeve tube;

[0037] 2, a plurality of type I medium tubes 2, arranged in the outer sleeve tube 1, each type I medium tube 2 is tangent to the outer sleeve tube 1;

[0038] 3, a plurality of type II medium tubes 3, arranged in the outer sleeve tube 1, each type I medium tube 2 is tangent to the outer sleeve tube 1. DETAILED DESCRIPTION

[0039] In order to more clearly understand the above-mentioned purposes, features and advantages of the present application, the present application will be further described in detail below with reference to the drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0040] In the following description, many specific details are set forth in order to provide a thorough understanding of the present application, however, the present application can also be implemented in other ways different from those described herein, therefore, the scope of protection of the present application is not limited by the specific embodiments disclosed below.

[0041] The following refers to Figures 1 to 9 A terahertz suspended core optical fiber according to some embodiments of the present application is described.

[0042] Embodiment One

[0043] A terahertz suspended core optical fiber, comprising:

[0044] an outer sleeve tube 1;

[0045] a plurality of type I medium tubes 2, arranged in the outer sleeve tube 1, each type I medium tube 2 is tangent to the outer sleeve tube 1;

[0046] a plurality of type II medium tubes 3, arranged in the outer sleeve tube 1, each type I medium tube 2 is tangent to the outer sleeve tube 1.

[0047] It should be noted that the radius of the type I medium tube 2 is greater than the radius of the type II medium tube 3.

[0048] It should be noted that there are no connection nodes between the plurality of type I medium tubes 2; there are no connection nodes between the plurality of type II medium tubes 3.

[0049] It should be noted that the tangent point between each I-type medium tube 2 and the outer sleeve tube 1 is a first tangent point; the tangent point between each I-type medium tube 2 and the II-type medium tube 3 tangent to the I-type medium tube 2 is a second tangent point.

[0050] The line between each first tangent point and the corresponding second tangent point passes through the center of the I-type medium tube 2 corresponding to the first tangent point.

[0051] It should be noted that the area surrounded by the outer walls of the plurality of II-type medium tubes 3 is a first hole 31, and the internal area of the II-type medium tube 3 is a second hole 32; the area surrounded by the outer walls of the plurality of I-type medium tubes 2, the outer walls of the plurality of II-type medium tubes 3, and the inner wall of the outer sleeve tube 1 is a third hole 21, and the internal area of the I-type medium tube 2 is a fourth hole 22.

[0052] It should be noted that the first hole 31, the second hole 32, and the plurality of II-type medium tubes 3 constitute a core; the third hole 21, the fourth hole 22, and the I-type medium tube 2 constitute a cladding, and the effective refractive index of the core is greater than the effective refractive index of the cladding, and the optical principle is a modified total internal reflection effect.

[0053] It should be noted that the first hole 31, the second hole 32, the third hole 21, and the fourth hole 22 are all filled with air.

[0054] It should be noted that the thickness of the outer sleeve tube 1 is greater than or equal to 0.2 mm, the thickness of the I-type medium tube 2 is 10 μm-100 μm; the thickness of the II-type medium tube 3 is 10 μm-100 μm.

[0055] It should be noted that the number of I-type medium tubes 2 is 3, 4, 5, or 6.

[0056] It should be noted that the materials of the outer sleeve tube 1, the I-type medium tube 2, and the II-type medium tube 3 are the same, and the material is any one of silica, soft glass, or plastic

[0057] It should be noted that the outer sleeve tube 1, the I-type medium tube 2, and the II-type medium tube 3 are all circular tubes

[0058] Referring to Figure 1 , Figure 2 , Figure 3 and Figure 4 , specifically, in the present embodiment, the thickness of the outer sleeve tube 1 is equal to 0.2 mm, the thickness of the I-type medium tube 2 is 20 μm; the thickness of the II-type medium tube 3 is 20 μm, the outer radius of the I-type medium tube 2 is 1.8 mm, and the outer radius of the II-type medium tube 3 is 350 μm; the number of I-type medium tubes 2 and II-type medium tubes 3 is both 4, and the radius of the inscribed circle of the first hole 31 is 300 μm.

[0059] It should be noted that, under the parameter conditions that the thickness of the outer sleeve 1 is equal to 0.2 mm, the thickness of the type I medium tube 2 is 20 μm, the thickness of the type II medium tube 3 is 20 μm, the outer radius of the type I medium tube 2 is 1.8 mm, the outer radius of the type II medium tube 3 is 350 μm, the number of the type I medium tube 2 and the type II medium tube 3 is both 4, and the radius of the inner circle of the first type of hole 31 is 300 μm:

[0060] When the working frequency is 0.5 THz, the confinement loss of the terahertz suspended core optical fiber in the embodiment is 5.57 x 10 - 4 dB / cm, and the absorption loss is 2.26 x 10 -2 dB / cm.

[0061] When the working frequency is in the range of 0.4 THz-1.2 THz, the terahertz suspended core optical fiber in the embodiment can achieve a confinement loss as low as 1.01 x 10 -13 dB / cm, and an absorption loss as low as 1.1 x 10 -2 dB / cm.

[0062] When the working frequency is in the range of 0.4 THz-0.7 THz, the terahertz suspended core optical fiber in the embodiment can achieve a total loss lower than 0.0868 dB / cm, and the low-loss bandwidth is 0.3 THz.

[0063] It should be noted that, by changing the thickness of the type I medium tube 2 and the type II medium tube 3, the dispersion variation curve under different frequencies is obtained. According to the calculation, when the thickness of the type I medium tube 2 and the type II medium tube 3 is both 10 μm, the terahertz suspended core optical fiber in the embodiment can achieve a dispersion of 0.17 ± 0.45 ps / THz / cm, when the thickness of the type I medium tube 2 and the type II medium tube 3 is both 15 μm, the terahertz suspended core optical fiber in the embodiment can achieve a dispersion of 0.48 ± 0.48 ps / THz / cm, when the thickness of the type I medium tube 2 and the type II medium tube 3 is both 20 μm, the terahertz suspended core optical fiber in the embodiment can achieve a dispersion of 0.45 ± 0.83 ps / THz / cm, and the dispersion of the terahertz suspended core optical fiber in the embodiment is almost flat in the range of 500 GHz (0.4-0.9 THz).

[0064] It should be noted that the confinement loss of the terahertz suspended core optical fiber in the embodiment is calculated by the following formula:

[0065]

[0066] wherein, L c represents the confinement loss, f represents the working frequency, c represents the speed of light, Im(n eff ) represents the imaginary part of the effective refractive index, and Im(n eff) varies with the outer radius of the class-I dielectric tube;

[0067] The absorption loss of the terahertz suspended core optical fiber of the embodiment is calculated by the following formula:

[0068]

[0069] wherein, α eff represents the absorption loss, ε0 represents the dielectric constant, μ0 represents the vacuum permeability, n mat represents the refractive index of the material, α mat represents the intrinsic EML of the bulk material, E represents the electric field component, S z represents the z-direction component of the Poynting vector, H * represents the magnetic field component, A represents the integral variable, α mat varies with the thickness of the class-I dielectric tube and the class-II dielectric tube.

[0070] The dispersion of the terahertz suspended core optical fiber of the embodiment is calculated by the following formula:

[0071]

[0072] wherein, β2 represents the dispersion, n eff represents the effective refractive index, ω represents the angular frequency, and c represents the speed of light.

[0073] According to the terahertz suspended core optical fiber of the embodiment, the modified total internal reflection principle is used, and the dependence on the thin arm in the manufacturing of the conventional suspended core optical fiber is avoided. This improvement has a positive impact on the optical fiber manufacturing process. The structure can ensure that most of the energy in the mode is distributed in the air hole, effectively reducing the absorption loss. The optical fiber core is supported by the support, effectively isolating the surrounding environment, reducing external interference, and improving the stability of the optical fiber. The optical fiber structure is simple, and all the boundaries are circular, which not only facilitates the manufacturing, but also enhances the anti-deformation ability of the optical fiber. The optical fiber has extremely low loss and wide and flat dispersion characteristics, ensuring high performance of the signal in long-distance transmission.

[0074] Embodiment two

[0075] A terahertz suspended core optical fiber comprises:

[0076] an outer sleeve 1;

[0077] a plurality of class-I dielectric tubes 2 arranged in the outer sleeve 1, each class-I dielectric tube 2 being tangent to the outer sleeve 1;

[0078] a plurality of class-II dielectric tubes 3 arranged in the outer sleeve 1, the number of the class-II dielectric tubes 3 being the same as that of the class-I dielectric tubes 2, and each class-I dielectric tube 2 being tangent to one class-II dielectric tube 3 on the outer wall of the class-I dielectric tube 2.

[0079] It should be noted that the radius of the first type medium tube 2 is greater than the radius of the second type medium tube 3.

[0080] It should be noted that there is no connection node between the plurality of first type medium tubes 2, and there is no connection node between the plurality of second type medium tubes 3.

[0081] It should be noted that the tangent point between each first type medium tube 2 and the outer sleeve tube 1 is a first tangent point, and the tangent point between each first type medium tube 2 and the second type medium tube 3 tangent to it is a second tangent point.

[0082] The line between each first tangent point and the corresponding second tangent point passes through the center of the first type medium tube 2 corresponding to the first tangent point.

[0083] It should be noted that the area surrounded by the outer walls of the plurality of second type medium tubes 3 is a first type hole 31, and the internal area of the second type medium tube 3 is a second type hole 32; the area surrounded by the outer walls of the plurality of first type medium tubes 2, the outer walls of the plurality of second type medium tubes 3, and the inner wall of the outer sleeve tube 1 is a third type hole 21, and the internal area of the first type medium tube 2 is a fourth type hole 22.

[0084] It should be noted that the first type hole 31, the second type hole 32, and the plurality of second type medium tubes 3 constitute a core; the third type hole 21, the fourth type hole 22, and the first type medium tube 2 constitute a cladding, and the effective refractive index of the core is greater than the effective refractive index of the cladding, and the optical principle is a modified total internal reflection effect.

[0085] It should be noted that the first type hole 31, the second type hole 32, the third type hole 21, and the fourth type hole 22 are all filled with air.

[0086] It should be noted that the thickness of the outer sleeve tube 1 is greater than or equal to 0.2 mm, the thickness of the first type medium tube 2 is 10 μm-100 μm; the thickness of the second type medium tube 3 is 10 μm-100 μm.

[0087] It should be noted that the number of first type medium tubes 2 is 3, 4, 5, or 6.

[0088] It should be noted that the materials of the outer sleeve tube 1, the first type medium tube 2, and the second type medium tube 3 are the same, and the material is any one of silica, soft glass, or plastic.

[0089] It should be noted that the outer sleeve tube 1, the first type medium tube 2, and the second type medium tube 3 are all circular tubes.

[0090] Referring to Figure 1 , Figure 5 and Figure 6As shown, specifically, in the present embodiment, the outer sleeve 1 has a thickness of 0.2 mm, the type I medium tube 2 has an outer radius of 1.0 mm, and the type II medium tube 3 has an outer radius of 170 μm; the number of the type I medium tube 2 and the type II medium tube 3 is both 4, and the radius of the inscribed circle of the first type of hole 31 is 160 μm.

[0091] It should be noted that, under the parameter conditions that the outer sleeve 1 has a thickness of 0.2 mm, the type I medium tube 2 has an outer radius of 1.0 mm, the type II medium tube 3 has an outer radius of 170 μm; the number of the type I medium tube 2 and the type II medium tube 3 is both 4, and the radius of the inscribed circle of the first type of hole 31 is 160 μm:

[0092] When the thickness of the type I medium tube 2 is 10 μm; the thickness of the type II medium tube 3 is 10 μm, and the working frequency is in the range of 0.69 THz-1.1 THz, the terahertz suspended-core optical fiber of the present embodiment can achieve a total loss of less than 0.0868 dB / cm and a low-loss bandwidth of 0.41 THz;

[0093] When the thickness of the type I medium tube 2 is 15 μm; the thickness of the type II medium tube 3 is 15 μm, and the working frequency is in the range of 0.594 THz-0.875 THz, the terahertz suspended-core optical fiber of the present embodiment can achieve a total loss of less than 0.0868 dB / cm and a low-loss bandwidth of 0.281 THz;

[0094] When the thickness of the type I medium tube 2 is 20 μm; the thickness of the type II medium tube 3 is 20 μm, and the working frequency is in the range of 0.535 THz-0.747 THz, the terahertz suspended-core optical fiber of the present embodiment can achieve a total loss of less than 0.0868 dB / cm and a low-loss bandwidth of 0.212 THz.

[0095] It should be noted that, by changing the thickness of the type I medium tube 2 and the type II medium tube 3, the dispersion variation curve under different frequencies is obtained, and according to the calculation, when the thickness of the type I medium tube 2 and the type II medium tube 3 is both 20 μm, the terahertz suspended-core optical fiber of the present embodiment can achieve a dispersion of 0.4±0.8 ps / THz / cm.

[0096] It should be noted that the confinement loss of the terahertz suspended-core optical fiber of the present embodiment is calculated by the following formula:

[0097]

[0098] wherein, L c represents the confinement loss, f represents the working frequency, c represents the speed of light, Im(n eff represents the imaginary part of the effective refractive index, and Im(n eff varies with the outer radius of the type I medium tube;

[0099] The absorption loss of the terahertz suspended core optical fiber of the embodiment is calculated by the following formula:

[0100]

[0101] wherein, α eff represents the absorption loss, ε0 represents the dielectric constant, μ0 represents the vacuum permeability, n mat represents the refractive index of the material, α mat represents the inherent EML of the bulk material, E represents the electric field component, S z represents the z-direction component of the Poynting vector, H * represents the magnetic field component, A represents the integral variable, α mat follows the thickness change of the type I dielectric tube and the type II dielectric tube.

[0102] The dispersion of the terahertz suspended core optical fiber of the embodiment is calculated by the following formula:

[0103]

[0104] wherein, β2 represents the dispersion, n eff represents the effective refractive index, ω represents the angular frequency, and c represents the speed of light.

[0105] According to the terahertz suspended core optical fiber of the embodiment, the modified total internal reflection principle is used, and the dependence on the thin arm in the manufacturing of the conventional suspended core optical fiber is avoided. This improvement has a positive impact on the optical fiber manufacturing process. The structure can ensure that most of the energy in the mode is distributed in the air hole, effectively reducing the absorption loss. The optical fiber core is supported by the support, effectively isolating the surrounding environment, reducing external interference, and improving the stability of the optical fiber. The optical fiber structure is simple, and all the boundaries are circular, which not only facilitates the manufacturing, but also enhances the deformation resistance of the optical fiber. The optical fiber has extremely low loss and wide and flat dispersion characteristics, ensuring high performance of the signal in long-distance transmission.

[0106] Embodiment three

[0107] A terahertz suspended core optical fiber comprises:

[0108] an outer sleeve 1;

[0109] a plurality of type I dielectric tubes 2 arranged in the outer sleeve 1, each type I dielectric tube 2 being tangent to the outer sleeve 1;

[0110] a plurality of type II dielectric tubes 3 arranged in the outer sleeve 1, the number of the type II dielectric tubes 3 being the same as that of the type I dielectric tubes 2, and each type I dielectric tube 2 being tangent to one type II dielectric tube 3 arranged on the outer wall of the type I dielectric tube 2.

[0111] It should be noted that the radius of the type I dielectric tube 2 is greater than the radius of the type II dielectric tube 3.

[0112] It should be noted that there is no connection node between the plurality of type I medium tubes 2; there is no connection node between the plurality of type II medium tubes 3.

[0113] It should be noted that the tangent point between each type I medium tube 2 and the outer sleeve tube 1 is a first tangent point; the tangent point between each type I medium tube 2 and the type II medium tube 3 tangent to it is a second tangent point.

[0114] The line between each first tangent point and the corresponding second tangent point passes through the center of the type I medium tube 2 corresponding to the first tangent point.

[0115] It should be noted that the area surrounded by the outer walls of the plurality of type II medium tubes 3 is a first type hole 31, and the internal area of the type II medium tube 3 is a second type hole 32; the area surrounded by the outer walls of the plurality of type I medium tubes 2, the outer walls of the plurality of type II medium tubes 3, and the inner wall of the outer sleeve tube 1 is a third type hole 21, and the internal area of the type I medium tube 2 is a fourth type hole 22.

[0116] It should be noted that the first type hole 31, the second type hole 32, and the plurality of type II medium tubes 3 constitute a core; the third type hole 21, the fourth type hole 22, and the type I medium tube 2 constitute a cladding, and the effective refractive index of the core is greater than the effective refractive index of the cladding, and the optical principle is the modified total internal reflection effect.

[0117] It should be noted that the first type hole 31, the second type hole 32, the third type hole 21, and the fourth type hole 22 are all filled with air.

[0118] It should be noted that the thickness of the outer sleeve tube 1 is greater than or equal to 0.2 mm, the thickness of the type I medium tube 2 is 10 μm-100 μm; the thickness of the type II medium tube 3 is 10 μm-100 μm.

[0119] It should be noted that the number of type I medium tubes 2 is 3, 4, 5, or 6.

[0120] It should be noted that the materials of the outer sleeve tube 1, the type I medium tube 2, and the type II medium tube 3 are the same, and the material is any one of silica, soft glass, or plastic.

[0121] It should be noted that the outer sleeve tube 1, the type I medium tube 2, and the type II medium tube 3 are all circular tubes.

[0122] Referring to Figure 7 It should be noted that in the present embodiment, the thickness of the outer sleeve tube 1 is equal to 0.2 mm, the outer radius of the type I medium tube 2 is 1.4 mm, and the outer radius of the type II medium tube 3 is 230 μm; the number of type I medium tubes 2 and type II medium tubes 3 is both 3, the radius of the inscribed circle of the first type hole 31 is 100 μm, the thickness of the type I medium tube 2 is 20 μm; the thickness of the type II medium tube 3 is 20 μm.

[0123] It should be noted that, in the parameter condition that the thickness of the outer sleeve 1 is equal to 0.2mm, the outer radius of the type I medium tube 2 is 1.4mm, the outer radius of the type II medium tube 3 is 230μm, the number of the type I medium tube 2 and the type II medium tube 3 is both 3, the radius of the inner circle of the first type hole 31 is 100μm, the thickness of the type I medium tube 2 is 20μm, and the thickness of the type II medium tube 3 is 20μm:

[0124] When the working frequency is 0.5THz, the confinement loss of the terahertz suspended core optical fiber in the embodiment is 3.32×10 - 3 dB / cm, and the absorption loss is 2.7×10 -2 dB / cm.

[0125] When the working frequency is in the range of 0.4THz-1.1THz, the terahertz suspended core optical fiber in the embodiment can realize a confinement loss as low as 1.3×10 -12 dB / cm, and an absorption loss as low as 1.31×10 -2 dB / cm.

[0126] When the working frequency is in the range of 0.4THz-0.73THz, the terahertz suspended core optical fiber in the embodiment can realize a total loss lower than 0.0868dB / cm, and a low-loss bandwidth of 0.33THz.

[0127] It should be noted that the confinement loss of the terahertz suspended core optical fiber in the embodiment is calculated by the following formula:

[0128]

[0129] Wherein, L c represents the confinement loss, f represents the working frequency, c represents the speed of light, Im(n eff ) represents the imaginary part of the effective refractive index, and Im(n eff ) changes with the change of the outer radius of the type I medium tube.

[0130] The absorption loss of the terahertz suspended core optical fiber in the embodiment is calculated by the following formula:

[0131]

[0132] Wherein, α eff represents the absorption loss, ε0 represents the dielectric constant, μ0 represents the vacuum permeability, n mat represents the refractive index of the material, α mat represents the intrinsic EML of the bulk material, E represents the electric field component, S z represents the z-direction component of the Poynting vector, H * represents the magnetic field component, and A represents the integral variable, α matThe thickness of the first type medium tube and the second type medium tube changes with the thickness of the outer sleeve tube.

[0133] According to the present embodiment, the terahertz suspended core optical fiber is based on the modified total internal reflection principle, avoiding the dependence on the thin arm in the manufacturing of the conventional suspended core optical fiber; this improvement has a positive impact on the optical fiber manufacturing process; such a structure can ensure that most of the energy in the mode is distributed in the air hole, effectively reducing the absorption loss; the optical fiber core is supported by the support, achieving effective isolation from the surrounding environment, reducing external interference, and improving the stability of the optical fiber. The optical fiber structure is simple, and all the boundaries are circular, which not only facilitates manufacturing, but also enhances the deformation resistance of the optical fiber. The optical fiber has extremely low loss and wide and flat dispersion characteristics, ensuring high performance of the signal in long-distance transmission.

[0134] Embodiment four

[0135] A terahertz suspended core optical fiber comprises:

[0136] An outer sleeve tube 1;

[0137] A plurality of first type medium tubes 2 are arranged in the outer sleeve tube 1, and each first type medium tube 2 is tangent to the outer sleeve tube 1.

[0138] A plurality of second type medium tubes 3 are arranged in the outer sleeve tube 1, and each first type medium tube 2 is tangent to one second type medium tube 3.

[0139] It should be noted that the radius of the first type medium tube 2 is greater than the radius of the second type medium tube 3.

[0140] It should be noted that there are no connection nodes between the plurality of first type medium tubes 2; there are no connection nodes between the plurality of second type medium tubes 3.

[0141] It should be noted that the tangent point between each first type medium tube 2 and the outer sleeve tube 1 is a first tangent point; the tangent point between each first type medium tube 2 and the second type medium tube 3 tangent to it is a second tangent point.

[0142] The line between each first tangent point and the corresponding second tangent point passes through the center of the first type medium tube 2 corresponding to the first tangent point.

[0143] It should be noted that the area surrounded by the outer wall of the plurality of second type medium tubes 3 is a first type hole 31, and the internal area of the second type medium tube 3 is a second type hole 32; the area surrounded by the outer wall of the plurality of first type medium tubes 2, the outer wall of the plurality of second type medium tubes 3, and the inner wall of the outer sleeve tube 1 is a third type hole 21, and the internal area of the first type medium tube 2 is a fourth type hole 22.

[0144] It should be noted that the first type of hole 31, the second type of hole 32 and the plurality of type II medium tubes 3 constitute the core; the third type of hole 21, the fourth type of hole 22 and the type I medium tube 2 constitute the cladding, the effective refractive index of the core is greater than the effective refractive index of the cladding, and the optical principle is the modified total internal reflection effect.

[0145] It should be noted that the first type of hole 31, the second type of hole 32, the third type of hole 21 and the fourth type of hole 22 are all filled with air.

[0146] It should be noted that the thickness of the outer sleeve 1 is greater than or equal to 0.2mm, the thickness of the type I medium tube 2 is 10μm-100μm; the thickness of the type II medium tube 3 is 10μm-100μm.

[0147] It should be noted that the number of type I medium tubes 2 is 3, 4, 5 or 6.

[0148] It should be noted that the material of the outer sleeve 1, the type I medium tube 2 and the type II medium tube 3 is the same, and the material is any one of silica, soft glass or plastic.

[0149] It should be noted that the outer sleeve 1, the type I medium tube 2 and the type II medium tube 3 are all circular tubes.

[0150] Referring to Figure 8 It should be noted that the thickness of the outer sleeve 1 is equal to 0.2mm, the outer radius of the type I medium tube 2 is 1.2mm, the outer radius of the type II medium tube 3 is 350μm; the number of type I medium tubes 2 and type II medium tubes 3 is both 5, the radius of the inscribed circle of the first type of hole 31 is 250μm, the thickness of the type I medium tube 2 is 20μm; the thickness of the type II medium tube 3 is 20μm.

[0151] It should be noted that under the parameter conditions that the thickness of the outer sleeve 1 is equal to 0.2mm, the outer radius of the type I medium tube 2 is 1.2mm, the outer radius of the type II medium tube 3 is 350μm; the number of type I medium tubes 2 and type II medium tubes 3 is both 5, the radius of the inscribed circle of the first type of hole 31 is 250μm, the thickness of the type I medium tube 2 is 20μm; the thickness of the type II medium tube 3 is 20μm:

[0152] When the working frequency is 0.5THz, the confinement loss of the terahertz suspended core optical fiber of the embodiment is 9.1×10 - 3 dB / cm, and the absorption loss is 2.85×10 -2 dB / cm.

[0153] When the working frequency is in the range of 0.4THz-1.1THz, the terahertz suspended core optical fiber of the embodiment can realize a confinement loss as low as 6.94×10 -14 dB / cm, and an absorption loss as low as 1.5×10-2 dB / cm;

[0154] When the working frequency is 0.41 THz-0.72 THz, the total loss of the terahertz suspended core optical fiber in the embodiment is less than 0.0868 dB / cm, and the low-loss bandwidth is 0.31 THz.

[0155] It should be noted that the confinement loss of the terahertz suspended core optical fiber in the embodiment is calculated by the following formula:

[0156]

[0157] Wherein, L c represents the confinement loss, f represents the working frequency, c represents the speed of light, Im(n eff ) represents the imaginary part of the effective refractive index, Im(n eff ) changes with the outer radius of the type I dielectric tube;

[0158] The absorption loss of the terahertz suspended core optical fiber in the embodiment is calculated by the following formula:

[0159]

[0160] Wherein, a eff represents the absorption loss, ε0 represents the dielectric constant, μ0 represents the vacuum permeability, n mat represents the refractive index of the material, a mat represents the intrinsic EML of the bulk material, E represents the electric field component, S z represents the z-direction component of the Poynting vector, H * represents the magnetic field component, A represents the integral variable, a mat changes with the thickness of the type I dielectric tube and the type II dielectric tube.

[0161] According to the terahertz suspended core optical fiber in the embodiment, based on the modified total internal reflection principle, the dependence of the traditional suspended core optical fiber on the thin arm in the manufacturing process is avoided; this improvement has a positive impact on the optical fiber manufacturing process; such structure can ensure that most of the energy in the mode is distributed in the air hole, effectively reducing the absorption loss; the optical fiber core is supported by the bracket, realizing effective isolation from the surrounding environment, reducing external interference, and improving the stability of the optical fiber. The optical fiber structure is simple, all the boundaries are circular, which not only facilitates manufacturing, but also enhances the deformation resistance of the optical fiber. The optical fiber has extremely low loss and wide and flat dispersion characteristics, ensuring high performance of the signal in long-distance transmission.

[0162] Embodiment five

[0163] A terahertz suspended core optical fiber comprises:

[0164] An outer sleeve 1;

[0165] a plurality of first medium tubes 2 are arranged in the outer sleeve 1, each first medium tube 2 is tangent to the outer sleeve 1;

[0166] a plurality of second medium tubes 3 are arranged in the outer sleeve 1, the number of the second medium tubes 3 is same as that of the first medium tubes 2, and each first medium tube 2 is tangent to one second medium tube 3.

[0167] It should be noted that the radius of the first medium tube 2 is greater than the radius of the second medium tube 3.

[0168] It should be noted that there is no connection node between the plurality of first medium tubes 2, and there is no connection node between the plurality of second medium tubes 3.

[0169] It should be noted that the tangent point between each first medium tube 2 and the outer sleeve 1 is a first tangent point, and the tangent point between each first medium tube 2 and the second medium tube 3 tangent to it is a second tangent point.

[0170] The line between each first tangent point and the corresponding second tangent point passes through the center of the first medium tube 2 corresponding to the first tangent point.

[0171] It should be noted that the area surrounded by the outer wall of the plurality of second medium tubes 3 is a first hole 31, and the internal area of the second medium tube 3 is a second hole 32; the area surrounded by the outer wall of the plurality of first medium tubes 2, the outer wall of the plurality of second medium tubes 3 and the inner wall of the outer sleeve 1 is a third hole 21, and the internal area of the first medium tube 2 is a fourth hole 22.

[0172] It should be noted that the first hole 31, the second hole 32 and the plurality of second medium tubes 3 constitute a core, the third hole 21, the fourth hole 22 and the first medium tube 2 constitute a cladding, the effective refractive index of the core is greater than the effective refractive index of the cladding, and the optical principle is the modified total internal reflection effect.

[0173] It should be noted that the first hole 31, the second hole 32, the third hole 21 and the fourth hole 22 are filled with air.

[0174] It should be noted that the thickness of the outer sleeve 1 is greater than or equal to 0.2 mm, the thickness of the first medium tube 2 is 10 μm-100 μm, and the thickness of the second medium tube 3 is 10 μm-100 μm.

[0175] It should be noted that the number of the first medium tube 2 is 3, 4, 5 or 6.

[0176] It should be noted that the material of the outer sleeve 1, the first medium tube 2 and the second medium tube 3 is the same, and the material is any one of silica, soft glass or plastic.

[0177] It should be noted that the outer sleeve 1, the type I medium tube 2 and the type II medium tube 3 are all circular tubes.

[0178] Referring to Figure 9 It is shown that, specifically, in the present embodiment, the outer sleeve 1 has a thickness of 0.2mm, the type I medium tube 2 has an outer radius of 1.0mm, and the type II medium tube 3 has an outer radius of 400μm; the number of the type I medium tube 2 and the type II medium tube 3 is both 6, the radius of the inscribed circle of the first type hole 31 is 420μm, the thickness of the type I medium tube 2 is 20μm, and the thickness of the type II medium tube 3 is 20μm.

[0179] It should be noted that, under the parameter conditions that the outer sleeve 1 has a thickness of 0.2mm, the type I medium tube 2 has an outer radius of 1.0mm, the type II medium tube 3 has an outer radius of 400μm; the number of the type I medium tube 2 and the type II medium tube 3 is both 6, the radius of the inscribed circle of the first type hole 31 is 420μm, the thickness of the type I medium tube 2 is 20μm, and the thickness of the type II medium tube 3 is 20μm:

[0180] When the working frequency is 0.5THz, the confinement loss of the terahertz suspended core optical fiber of the present embodiment is 6.06×10 - 2 dB / cm, and the absorption loss is 2.54×10 -2 dB / cm.

[0181] When the working frequency is in the range of 0.4THz-1.1THz, the terahertz suspended core optical fiber of the present embodiment can achieve a confinement loss as low as 8.01×10 -12 dB / cm, and an absorption loss as low as 1.32×10 -2 dB / cm.

[0182] When the working frequency is in the range of 0.5THz-0.71THz, the terahertz suspended core optical fiber of the present embodiment can achieve a total loss lower than 0.0868dB / cm, and the low-loss bandwidth is 0.21THz.

[0183] It should be noted that the confinement loss of the terahertz suspended core optical fiber of the present embodiment is calculated by the following formula:

[0184]

[0185] wherein, L c represents the confinement loss, f represents the working frequency, c represents the speed of light, Im(n eff ) represents the imaginary part of the effective refractive index, and Im(n eff ) varies with the outer radius of the type I medium tube.

[0186] The absorption loss of the terahertz suspended core optical fiber of the present embodiment is calculated by the following formula:

[0187]

[0188] wherein, α eff represents absorption loss, ε0represents dielectric constant, μ0represents vacuum permeability, n mat represents the refractive index of the material, α mat represents the intrinsic EML of the bulk material, E represents the electric field component, S z represents the z-direction component of the Poynting vector, H * represents the magnetic field component, A represents the integral variable, α mat follows the thickness change of the type I dielectric tube and the type II dielectric tube.

[0189] According to the terahertz suspended core optical fiber of the embodiment, the modified total internal reflection principle is used, the dependence on the thin arm in the manufacturing of the conventional suspended core optical fiber is avoided, the improvement has a positive influence on the optical fiber manufacturing process, most of the energy in the mode is distributed in the air hole, the absorption loss is effectively reduced, the optical fiber core is supported by the support, the effective isolation from the surrounding environment is realized, the external interference is reduced, and the stability of the optical fiber is improved. The optical fiber structure is simple, all the boundaries are circular, which not only facilitates the manufacturing, but also enhances the deformation resistance of the optical fiber. The optical fiber has extremely low loss and wide and flat dispersion characteristics, and the high performance of the signal in long distance transmission is ensured.

[0190] In the present application, the term "a plurality of" refers to two or more, unless otherwise explicitly limited. The terms "mount", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, "connect" can be fixed connection, or detachable connection, or integrally connected; "connected" can be directly connected, or indirectly connected through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0191] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "specific embodiments" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present application, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0192] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A terahertz suspended core optical fiber, characterized in that, include: Outer tube (1); Multiple Class I media tubes (2) are disposed inside the outer sleeve (1), and each Class I media tube (2) is tangent to the outer sleeve (1); Multiple Type II media tubes (3) of the same number as the Type I media tubes (2) are disposed inside the outer sleeve (1), and one Type II media tube (3) is disposed tangentially on the outer wall of each Type I media tube (2). The area enclosed by the outer walls of multiple Class II dielectric tubes (3) is a Class I hole (31), and the inner area of ​​the Class II dielectric tubes (3) is a Class II hole (32); the area enclosed by the outer walls of multiple Class I dielectric tubes (2), the outer walls of multiple Class II dielectric tubes (3), and the inner wall of the outer sleeve (1) is a Class III hole (21), and the inner area of ​​the Class I dielectric tubes (2) is a Class IV hole (22). The Class I hole (31), the Class II hole (32), and the multiple Class II dielectric tubes (3) constitute the fiber core; the Class III hole (21), the Class IV hole (22), and the Class I dielectric tubes (2) constitute the cladding. The effective refractive index of the fiber core is greater than that of the cladding, and its optical principle is a modified total internal reflection effect. The tangent point between each of the Class I media tubes (2) and the outer tube (1) is the first tangent point, and the tangent point between each of the Class I media tubes (2) and the Class II media tube (3) that is tangent to it is the second tangent point; The line connecting each first tangent point and the corresponding second tangent point passes through the center of the type I medium tube (2) corresponding to the first tangent point; Among them, the outer tube (1), the type I medium tube (2) and the type II medium tube (3) are all circular tubes; the radius of the type I medium tube (2) is greater than the radius of the type II medium tube (3).

2. The terahertz suspended core optical fiber according to claim 1, characterized in that, There are no connection nodes between multiple Class I media tubes (2); there are no connection nodes between multiple Class II media tubes (3).

3. The terahertz suspended core optical fiber according to claim 1, characterized in that, The first type of hole (31), the second type of hole (32), the third type of hole (21) and the fourth type of hole (22) are all filled with air.

4. A terahertz suspended core optical fiber according to claim 1, characterized in that, The outer tube (1) has a thickness greater than or equal to 0.2 mm, the Class I medium tube (2) has a thickness of 10 μm-100 μm, and the Class II medium tube (3) has a thickness of 10 μm-100 μm.

5. A terahertz suspended core optical fiber according to claim 1, characterized in that, The number of the Class I media tubes (2) is 3, 4, 5 or 6.

6. A terahertz suspended core optical fiber according to claim 1, characterized in that, The outer tube (1), the type I medium tube (2), and the type II medium tube (3) are made of the same material, which is any one of silicon dioxide, soft glass, or plastic.

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