Integrated photonic circuit and set consisting of an integrated photonic circuit of this type and an optical fiber
Patent Information
- Application Number
- EP2024798826
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2023-10-31
- Filing Date
- 2024-10-28
- Publication Date
- 2026-09-09
AI Technical Summary
Existing integrated photonic circuits face challenges in achieving high coupling efficiency between optical fibers and waveguides, particularly due to complex waveguide transitions and material refractive index differences, which complicate the production process.
The integrated photonic circuit features a waveguide with a defense section and a coupling device that tapers in opposite directions, allowing for broadband and highly efficient coupling. The waveguide transitions from a rib structure to a strip structure, with the coupling device covering the transition section, enabling efficient light coupling.
This solution simplifies the production process and optimizes coupling efficiency, enabling reliable and accurate transmission of optical signals in applications like quantum computers and telecommunications systems.
Smart Images
Figure EP2024080453_08052025_PF_FP_ABST
Abstract
Description
[0001] Integrated photonic circuit and a set comprising such an integrated photonic circuit and an optical fiber
[0002] Description
[0003] The invention relates to an integrated photonic circuit having features of claim 1 and a set consisting of at least one such integrated photonic circuit and at least one optical fiber having features of claim 13.
[0004] One of the most common methods for coupling light into or out of a chip-integrated waveguide using a fiber is so-called edge coupling. In edge coupling, the respective ends of the fiber and the waveguide are aligned in the same direction.
[0005] For a highly efficient fiber-to-chip interface of an integrated photonic circuit, the waveguide mode must be matched to the fiber mode to achieve high mode overlap. Tapered waveguide transitions and / or connecting sections can be used for this purpose.
[0006] CN 115793140 A discloses a tapered waveguide with a coupling device, wherein the waveguide and the coupling device are each tapered in opposite directions to increase coupling efficiency. The implementation of such waveguide transitions is often complex. It is therefore an object of the present invention to provide an integrated photonic circuit and a set comprising at least one integrated photonic circuit and at least one fiber, wherein production can be implemented using simple means and coupling efficiency can be optimized.
[0007] The above object is achieved by an integrated photonic circuit having the features of claim 1. The integrated photonic circuit comprises at least one waveguide for guiding light and at least one coupling device for coupling light into the waveguide and / or for coupling light out of the waveguide. The waveguide can have a cross-section of 0.6 pm (micrometers) by 1 pm.
[0008] The waveguide has at least one end for coupling in and / or out light. The waveguide has a tapered section at its end. The tapered section extends partially, in particular completely, along a longitudinal direction. The waveguide is tapered along the tapered section towards the end of the waveguide. The tapered section can have a length of 400 pm.
[0009] The tapered section of the waveguide has a first section and a second section. In the first section, the waveguide is designed as a rib waveguide (semi-etched, rib waveguide). In the second section, the waveguide is designed as a strip waveguide (fully etched, strip waveguide). The first section and the second section are adjacent to one another. The waveguide designed as a rib waveguide (semi-etched) can be arranged on a waveguide layer whose layer thickness decreases continuously and steadily in the longitudinal direction until it is zero, in particular at the transition between the first section and the second section. In other words, no waveguide layer is formed in the second section (or the thickness of the waveguide layer is zero in the second section).
[0010] The coupling device covers the tapered section, in particular the second section, at least in part. The coupling device is tapered at least in part, in particular completely, along the longitudinal direction, toward the end of the waveguide. The waveguide and the coupling device are tapered, in particular, in opposite directions.
[0011] This enables broadband and highly efficient coupling. This enables applications such as quantum computers and telecommunications systems, which rely on high coupling efficiencies to ensure reliable and accurate transmission of optical signals between individual components, to be implemented. The modes of the waveguide and the fiber can be converted with high coupling efficiency.
[0012] With the help of transitions to very small strip waveguides (which are realized by a full etching step of the waveguide layer, e.g., LNOI (lithium niobate on insulator)), it becomes possible to "squeeze" the light from the waveguide (higher refractive index) into the coupling device or a specific cladding layer (lower refractive index). The enlargement of the waveguide mode (within the coupling device) enables highly efficient coupling between waveguides and fibers.
[0013] According to a further development of the integrated photonic circuit, the waveguide in the tapered section and / or the coupling device can each be configured to taper in a width direction along the longitudinal direction. Alternatively or additionally, the waveguide in the tapered section and / or the coupling device can each be configured to taper in a height direction along the longitudinal direction. In other words, the width and / or height of the waveguide in the tapered section and / or the coupling device can decrease along the longitudinal direction in the direction of the respective taper.
[0014] This allows the respective mode in the waveguide or coupling device to be adjusted in height (vertical) and width (lateral). This allows for (almost) adiabatic mode narrowing or conversion.
[0015] According to a further development of the integrated photonic circuit, the tapered section can be configured to taper continuously along the longitudinal direction. Alternatively or additionally, the coupling device can be configured to taper continuously along the longitudinal direction.
[0016] This allows for (nearly) adiabatic mode narrowing or conversion. To achieve this, the waveguide's cross-section can be changed longitudinally (toward the end of the waveguide) slowly enough to satisfy the adiabatic transmission conditions. This leads to losses being avoided or at least reduced.
[0017] According to a development of the integrated photonic circuit, the integrated photonic circuit can comprise at least two gaps. The gaps can extend along the longitudinal direction. The tapered section and / or the coupling device can be arranged, in particular centrally, between the two gaps. The two gaps can each laterally delimit the tapered section and / or the coupling device with respect to the longitudinal direction. The gaps can be designed as air gaps. The gaps can be designed as etched trenches. The gaps can penetrate the waveguide layer and / or the chip at least partially, in particular completely.
[0018] This allows the mode guidance to be further improved.
[0019] According to a further development of the integrated photonic circuit, the coupling device can be formed at least partially, in particular completely, from at least one polymer and / or silicon nitride.
[0020] This allows the coupling device to be implemented using simple means.
[0021] According to a further development of the integrated photonic circuit, the coupling device can be manufactured using a 3D printing process. This allows the coupling device to be manufactured using simple means. The coupling device (e.g., made of polymer) can be simply printed onto a chip.
[0022] According to a further development of the integrated photonic circuit, the coupling device can have two side sections. The tapered section, in particular the second section, can be arranged at least partially between the two side sections. The side sections and the tapered section arranged between the two side sections, in particular the second section, can be covered at least partially by a covering layer.
[0023] This allows the coupling device to be implemented using simple means. A polymer printing process is also unnecessary. This allows for lateral mode guidance along the width direction through the two side sections and vertical mode guidance along the height direction through the cover layer.
[0024] According to a further development of the integrated photonic circuit, the side sections can be formed at least partially, in particular entirely, from silicon dioxide. The cover layer can be formed at least partially, in particular entirely, from silicon nitride.
[0025] This allows the mode to be optimally enclosed or guided and converted within the coupling device. According to a further development of the integrated photonic circuit, the covering layer can be formed from several alternately arranged layers of silicon dioxide and silicon nitride. The individual layers can be deposited, for example, using standard CVD (chemical vapor deposition) processes.
[0026] This can prevent or at least reduce stress in the (relatively thick) silicon nitride covering layer, which could otherwise lead to a possible crack in the covering layer.
[0027] According to a further development of the integrated photonic circuit, the coupling device can have a coupling surface for coupling light into the coupling device and / or for coupling light out of the coupling device. The coupling surface can be arranged at an angle to the longitudinal direction, the width direction, and / or the height direction. This angle can be a Brewster angle.
[0028] At the Brewster angle, minimal reflections (theoretically no reflections) occur for parallel polarized light, which can lead to maximum transmission. The Brewster angle depends on the refractive indices of the respective materials at the interface. The Brewster angle can be calculated using the following formula:
[0029] Where 0 is the Brewster angle, nl is the refractive index of the material from which the light beam emerges and n2 is the refractive index of the material into which the light beam enters. Thus, the Brewster angle for a glass-air transition (n G ias = 1.5 and n Luft = 1) is approximately 34°. For a silicon nitride-glass transition, the Brewster angle is 54°. The Brewster angle can be calculated for transitions between different materials. The geometry of the coupling device, especially the coupling surface, can thus be adapted to different materials.
[0030] This allows Fresnel losses (due to differences in refractive index) to be avoided or at least reduced.
[0031] According to a further development of the integrated photonic circuit, the coupling device can be arranged on a chip. The coupling device can protrude from the chip at least in sections, in particular with the coupling surface, along the longitudinal direction.
[0032] The chip can consist of a silicon layer as the base and a (thin) silicon dioxide layer (buffer layer) arranged on the silicon layer. The waveguide layer can be arranged on the silicon dioxide layer. In other words, a silicon dioxide layer (buffer layer) can be arranged between the waveguide layer and the base (silicon layer) of the chip.
[0033] This allows the fiber to be brought into contact with the coupling surface of the coupling device, with the fiber being arranged at a distance from the chip. This increases the tolerance in the contact between the fiber and the coupling surface of the coupling device. The negative influence (or interference) of the chip or any irregularities present on the chip (or their geometry) can be prevented or at least reduced.
[0034] According to a further development of the integrated photonic circuit, the waveguide (or the waveguide layer) can be formed from lithium niobate, silicon nitride, barium titanate, aluminum oxide, aluminum nitride, titanium dioxide, silicon carbide, silicon, gallium phosphide, silicon oxynitride, gallium arsenide, gallium nitride, indium phosphide, chalcogenide, lithium tantalate, diamond and / or an electroactive polymer compound.
[0035] This allows the waveguide to be used flexibly and adapted to different applications and materials.
[0036] According to a further development of the integrated photonic circuit, the tapered section, in particular the second section, can be produced at least in sections, in particular completely, by means of ion beam milling or cathode sputtering.
[0037] This allows the thickness of the waveguide layer to be processed or thinned. The continuous reduction in thickness of the waveguide layer in the longitudinal direction (toward the coupling device) can thus be implemented simply and precisely. Thus, with a single (subsequent) etching step, the first section, in which the waveguide has a rib structure, and the second section, in which the waveguide has a stripe structure, can be implemented. Further etching steps are unnecessary.
[0038] If the layer thickness of the waveguide layer reduced by ion thinning or cathode sputtering is smaller than the etching depth of the etching step for the formation of the waveguide in the second section, both a complete etching step in the second section for the strip waveguide and a partial etching step for the ridge waveguide in the first section can be realized.
[0039] The above object is achieved by a set having the features of claim 13. The set comprises at least one integrated photonic circuit according to the above embodiments and at least one optical fiber. The fiber can be a single-mode fiber.
[0040] With regard to the advantages that can be achieved, reference is made to the relevant explanations regarding the integrated photonic circuit. The measures described in connection with the integrated photonic circuit and / or those explained below can be used to further configure the set.
[0041] According to a further development of the set, the optical fiber can have one end with a fiber surface for coupling light out of the fiber and / or for coupling light into the fiber. The fiber surface and the coupling surface of the coupling device can be plane-parallel to one another. This allows the fiber and the coupling device to be precisely matched to one another or brought into precise contact. This allows a precise transition between the coupling surface and the fiber surface to be implemented.
[0042] According to a further development of the set, several waveguides and / or several fibers can be arranged next to one another on the integrated photonic circuit.
[0043] This allows arrays of waveguides or fibers, which are arranged parallel to each other, to be implemented on a (single) integrated photonic circuit.
[0044] Further features, details and advantages of the invention will become apparent from the wording of the claims and from the following description of embodiments with reference to the drawings. They show schematically:
[0045] Fig. 1 shows a detail of a perspective view of an integrated photonic circuit according to a first embodiment;
[0046] Fig. 2 shows a section of a sectional view of the integrated photonic circuit according to a second embodiment;
[0047] Fig. 3 shows a section of a sectional view of the integrated photonic circuit according to a third embodiment; Fig. 4 shows a section of a side view of the integrated photonic circuit according to a fourth embodiment;
[0048] Fig. 5 shows a section of a side view of the integrated photonic circuit according to a fifth embodiment;
[0049] Fig. 6 shows a section of a plan view of the integrated photonic circuit according to a sixth embodiment;
[0050] Fig. 7 shows a section of a plan view of the integrated photonic circuit according to a seventh embodiment;
[0051] Fig. 8 shows a detail of a perspective sectional view of the integrated photonic circuit according to an eighth embodiment.
[0052] In the following description and in the figures, corresponding components and elements have the same
[0053] Reference symbols. For the sake of clarity, not all reference symbols are shown in all figures.
[0054] Figure 1 shows a section of a perspective view of an integrated photonic circuit 10 according to a first embodiment.
[0055] The integrated photonic circuit 10 comprises at least one waveguide 12 for guiding light and at least one coupling device 14 for coupling light into the waveguide 12 and / or for coupling light out of the waveguide 12. The waveguide 12 is exposed in Figure 1. In other words, air or a vacuum can be arranged above the waveguide 12. In practice, for example, after the waveguide 12 has been formed and / or the coupling device 14 has been attached, a cover layer 26 (cf. Figure 2), for example made of silicon dioxide or polymer adhesive, can be applied. The cover layer 26 can protect the waveguide 12 and improve the optical properties.
[0056] The waveguide 12 has at least one end 16 for coupling in and / or out light. At its end 16, the waveguide 12 has a tapered section 18. The tapered section 18 extends at least partially, in particular completely, along a longitudinal direction 11. The waveguide 12 is tapered along the tapered section 18 towards the end 16 of the waveguide 12. In other words, a cross-section of the waveguide 12 becomes smaller towards the end 16 of the waveguide 12.
[0057] The tapered section 18 has a first section 20 and a second section 22. In the first section 20, the waveguide 12 is designed as a rib waveguide (half-etched). In the second section 22, the waveguide 12 is designed as a strip waveguide (fully etched). The first section 20 and the second section 22 are adjacent to one another.
[0058] The coupling device 14 covers the tapered section 18, in this case the second section 22, in sections. It is also conceivable for the coupling device 14 to completely cover the tapered section 18, in particular the second section 22. In this case, the coupling device 14 is designed to taper in sections along the longitudinal direction 11, towards the end 16 of the waveguide 12. It is also conceivable for the coupling device 14 to be designed to taper completely along the longitudinal direction 11, towards the end 16 of the waveguide 12. The coupling device 14 and the tapered section 18 of the waveguide 12 are designed to taper in opposite directions.
[0059] In the present case, the waveguide 12 tapers along the longitudinal direction 11 in a width direction 13 and a height direction 15. In other words, the height and width of the waveguide 12 decrease towards the end 16 of the waveguide 12. In the present case, the coupling device 14 tapers along the longitudinal direction in the width direction 13 and the height direction 15. In other words, the height and width of the coupling device 14 decrease towards the end 16 of the waveguide 12.
[0060] Thus, a mode matching between the mode in the waveguide 12 and the mode in the coupling device 14 along the width direction 13 and along the height direction 15 can be implemented.
[0061] In the present case, the tapered section 18 and the coupling device 14 are each designed to taper continuously along the longitudinal direction 11. The tapered section 18 of the waveguide 12 and the coupling device 14 are designed to taper in opposite directions in the longitudinal direction 11. In particular, the waveguide 12 provides a continuous and steady transition of the waveguide 12 (or its cross-section) from the first section 20 to the second section 22.
[0062] The tapered section 18, in particular the second section 22, can be produced at least in sections, in particular completely, by means of ion thinning or cathode sputtering.
[0063] The coupling device 14 is made of polymer in the present case. The coupling device 14 can be manufactured using a 3D printing process. For example, the coupling device 14 can be realized by printing the polymer onto (e.g., onto a chip 32).
[0064] The coupling device 14 is arranged on a chip 32. In the second section 22, the waveguide 12 is arranged directly on the chip 32 as a strip waveguide. In the first section 20, the waveguide 12 is arranged along with a waveguide layer 21 as a rib waveguide, in the first section 20. The waveguide layer 21 has a thickness that decreases continuously in the longitudinal direction 11.
[0065] In the present case, the chip 32 consists of a silicon layer as a base and a (thin) silicon dioxide layer (buffer layer) arranged on the silicon layer. The waveguide layer 21 is arranged on the silicon dioxide layer. In other words, a silicon dioxide layer (buffer layer) is arranged between the waveguide layer 21 and the base (silicon layer) of the chip 32. For reasons of clarity, neither the base layer (silicon layer) nor the buffer layer (silicon dioxide layer) of the chip 32 is shown.
[0066] The waveguide 12 and / or the waveguide layer 21 can each be formed from lithium niobate, silicon nitride, barium titanate, aluminum oxide, aluminum nitride, titanium dioxide, silicon carbide, silicon, gallium phosphide, silicon oxynitride, gallium arsenide, gallium nitride, indium phosphide, chalcogenide, lithium tantalate, diamond and / or an electroactive polymer compound.
[0067] The coupling device 14 has a coupling surface 28 for coupling light into the coupling device 14 and / or for coupling light out of the coupling device 14. An optical fiber 36 is used for coupling or decoupling light. The optical fiber 36 has an end 38 which has a fiber surface 40 for coupling light out of the fiber 36 and / or for coupling light into the fiber 36 (cf. Figures 4 to 7). The fiber surface 40 of the fiber 36 and the coupling surface 28 of the coupling device 14 are designed to be plane-parallel to one another in the present case.
[0068] On the integrated photonic circuit 10, several waveguides 12 and / or several fibers 36 can be arranged next to one another (for example in an array) (not shown).
[0069] Figure 2 shows a section of a sectional view of the integrated photonic circuit 10 according to a second exemplary embodiment. Figure 2 shows a section transverse to the longitudinal direction 11. The second exemplary embodiment differs from the first exemplary embodiment shown in Figure 1 in the following:
[0070] The coupling device 14 has two side sections 24. The tapered section 18, in particular the second section 22, is arranged at least in sections between the two side sections 24. The side sections 24 and the section of the waveguide 12 arranged between the side sections 24 are each arranged on the chip 32. In the present case, a cover layer 26 covers at least in sections the two side sections 24 and the section of the waveguide 12 arranged between the two side sections 24.
[0071] The covering layer 26 can be applied after the formation or production of the waveguide 12. The covering layer 26 can be deposited evenly over the waveguide layer 21 or the waveguide 12. As a result, the contour of the waveguide 12 and / or the side sections 24 can be transferred upwards onto the surface (with respect to the height direction 15) of the covering layer 26, as shown here in Figure 2.
[0072] The side sections 24 can be formed at least partially, in particular entirely, from silicon dioxide. The cover layer 26 can be formed at least partially, in particular entirely, from silicon nitride.
[0073] Thus, mode matching (or guiding) between the mode in the waveguide 12 and the mode in the coupling device 14 along the width direction 13 can be implemented by the two side sections 24. Mode matching (or guiding) between the mode in the waveguide 12 and the mode in the coupling device 14 along the height direction 15 can be implemented by the covering layer 26.
[0074] Figure 3 shows a section of a sectional view of the integrated photonic circuit 10 according to a third embodiment. The third embodiment differs from the second embodiment shown in Figure 2 in the following:
[0075] The cover layer 26 is formed from several alternating layers of silicon dioxide and silicon nitride. Thus, the bottom layer and each subsequent layer are formed as a silicon nitride layer 27. A silicon dioxide layer 29 is arranged between each of the silicon nitride layers 27. This prevents or at least reduces stresses in the cover layer 26.
[0076] Figure 4 shows a section of a side view of the integrated photonic circuit 10 according to a fourth embodiment. The fourth embodiment differs from the first embodiment shown in Figure 1 in the following:
[0077] In the present case, the coupling surface 28 of the coupling device 14 is arranged at an angle to the longitudinal direction 11 and the vertical direction 15. The surface normal 17 of the coupling surface 28 forms an angle 30 with the longitudinal direction 11. Thus, the coupling surface 28 is oriented at an angle 30 to the vertical direction 15. The angle 30 corresponds in this case to a Brewster angle.
[0078] Since the fiber surface 40 and the coupling surface 28 are arranged plane-parallel to one another, the fiber surface 40 is oriented analogously to the coupling surface 28 (i.e., it is arranged at an incline similar to the coupling surface 28). In the present case, the fiber surface 40 and the coupling surface 28 are arranged at a distance from one another. In the present case, the lower edge of the coupling device 14 with respect to the vertical direction 15 is flush with the chip 32.
[0079] Figure 5 shows a section of a side view of the integrated photonic circuit 10 according to a fifth embodiment. The fifth embodiment differs from the fourth embodiment shown in Figure 4 in the following:
[0080] The fiber surface 40 and the coupling surface 28 (cf. Figure 4) are in contact with one another in the present case. The coupling device 14 protrudes from the chip 32 along the longitudinal direction 11. In this way, the fiber surface 40 and the coupling surface 28 can be brought into contact without the fiber 36 coming into contact with the chip 32. Thus, the contact between the fiber surface 40 and the coupling surface 28 is not (negatively) influenced or disturbed by the chip 32 or possible irregularities 33 arranged on the chip 32.
[0081] Figure 6 shows a section of a top view of the integrated photonic circuit 10 according to a sixth embodiment. The sixth embodiment differs from the fifth embodiment shown in Figure 5 in the following:
[0082] In the present case, the coupling surface 28 of the coupling device 14 is arranged at an angle to the longitudinal direction 11 and the width direction 13. The surface normal 17 of the coupling surface 28 forms an angle 30 with the longitudinal direction 11. Thus, the coupling surface 28 is oriented at an angle 30 to the width direction 13. The angle 30 corresponds in this case to the Brewster angle.
[0083] Since the fiber surface 40 and the coupling surface 28 are arranged plane-parallel to each other, the fiber surface 40 is oriented analogously to the coupling surface 28 (i.e., arranged at an incline in the same way as the coupling surface 28).
[0084] Figure 7 shows a section of a top view of the integrated photonic circuit 10 according to a seventh embodiment. The seventh embodiment differs from the sixth embodiment shown in Figure 6 in the following:
[0085] The fiber surface 40 and the coupling surface 28 are arranged at a distance from one another.
[0086] Figure 8 shows a detail of a perspective sectional view of the integrated photonic circuit 10 according to an eighth exemplary embodiment. Figure 8 shows a section transverse to the longitudinal direction 11. The eighth exemplary embodiment differs from the second exemplary embodiment shown in Figure 2 in the following way: In the present case, the integrated photonic circuit 10 has two gaps 37 instead of the two side sections 24. The two gaps 37 extend along the longitudinal direction 11. In other words, the gaps 37 are oriented parallel to the longitudinal direction 11. The tapered section 18 and / or the coupling device 14 can be arranged, in particular centrally, between the two gaps 37. In the present case, a (silicon) volume is recessed in the chip 32 below the two gaps 37 (with respect to the height direction 15). This makes it possible to minimize optical losses and further improve mode matching.
[0087] The integrated photonic circuit 10 and fiber 36 shown in the figures may represent a set 34. The integrated photonic circuit 10 according to the above embodiments and the optical fiber 36 according to the above embodiments may together form the set 34.
Claims
Patent claims 1. Integrated photonic circuit (10) with at least one Waveguide (12) for guiding light and at least one coupling device (14) for coupling light into the Waveguide (12) and / or for coupling out light from the waveguide (12), - wherein the waveguide (12) has at least one end (16) for coupling in and / or coupling out light, - wherein the waveguide (12) has a tapered section (18) at its end (16), - wherein the tapered section (18) extends at least partially, in particular completely, along a longitudinal direction (11), - wherein the waveguide (12) extends along the Tapered section (18) to the end (16) of the waveguide (12) is tapered, - wherein the tapered section (18) has a first section (20) in which the waveguide (12) is designed as a rib waveguide, - wherein the tapered section (18) has a second section (22) adjacent to the first section (20), in which the waveguide (12) is designed as a strip waveguide, - wherein the coupling device (14) covers the tapered section (18), in particular the second section (22), at least in sections, - in particular wherein the coupling device (14) is tapered at least in sections, in particular completely, along the longitudinal direction (11) towards the end (16) of the waveguide (12).
2. Integrated photonic circuit (10) according to claim 1, characterized in that the waveguide (12) in the tapered section (18) and / or the coupling device (14) is tapered along the longitudinal direction (11) in a width direction (13) and / or in a height direction (15).
3. Integrated photonic circuit (10) according to claim 1 or 2, characterized in that the tapering section (18) and / or the coupling device (14) are designed to taper continuously at least partially, in particular completely, along the longitudinal direction (11).
4. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the integrated photonic circuit (10) comprises at least two gaps (37), wherein the gaps (37) extend along the longitudinal direction (11), wherein the tapered section (18) and / or the coupling device (14) are arranged between the two columns (37).
5. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the coupling device (14) is formed at least partially, in particular completely, from at least one polymer.
6. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the coupling device (14) is manufactured by means of a 3D printing process.
7. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the coupling device (14) has two side sections (24), wherein the tapered section (18), in particular the second section (22), is arranged at least in sections between the two side sections (24), wherein the side sections (24) and the tapered section (18), in particular the second section (22), arranged between the two side sections (24), are covered at least in sections by a cover layer (26).
8. Integrated photonic circuit (10) according to the preceding claim, characterized in that the side sections (24) are formed at least partially, in particular completely, from silicon dioxide and the cover layer (26) is formed at least partially, in particular completely, from silicon nitride.
9. Integrated photonic circuit (10) according to one of the two preceding claims, characterized in that the cover layer (26) is formed from several alternately arranged layers (27, 29) of silicon dioxide and silicon nitride.
10. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the coupling device (14) has a coupling surface (28) for coupling light into the coupling device (14) and / or for coupling light out of the coupling device (14), wherein the coupling surface (28) is arranged inclined by an angle (30) to the longitudinal direction (11), the width direction (13) and / or the height direction (15), in particular wherein the angle (30) is a Brewster angle.
11. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the Coupling device (14) is arranged on a chip (32) and protrudes at least in sections, in particular with the coupling surface (28), along the longitudinal direction (11) from the chip (32).
12. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the waveguide (12) and / or a waveguide layer (21) is formed from lithium niobate, silicon nitride, barium titanate, aluminum oxide, aluminum nitride, titanium dioxide, silicon carbide, silicon, gallium phosphide, silicon oxynitride, gallium arsenide, gallium nitride, indium phosphide, chalcogenide, lithium tantalate, diamond and / or an electroactive polymer compound.
13. Integrated photonic circuit (10) according to one of the preceding claims, characterized in that the tapered section (18), in particular the second section (22), is produced at least in sections, in particular completely, by means of ion thinning or cathode sputtering.
14. Set (34) consisting of at least one integrated photonic circuit (10) according to one of the above claims and at least one optical fiber (36).
15. Set (34) according to the preceding claim, characterized in that the optical fiber (36) has an end (38) which has a fiber surface (40) for coupling light out of the fiber (36) and / or for coupling light into the fiber (36), wherein the fiber surface (40) and the coupling surface (28) of the coupling device (14) are formed plane-parallel to one another. Set (34) according to one of the two preceding claims, characterized in that a plurality of waveguides (12) and / or a plurality of fibers (36) are arranged next to one another on the integrated photonic circuit (10).