Quantum light source device

Abstract

A quantum light source device according to the present embodiment comprises: an optical fiber for transferring excitation light; a quantum light source to which the excitation light is provided to enable the quantum light source to provide a quantum signal to the optical fiber, the quantum light source being disposed at an end of the optical fiber; a thermally conductive material for coating the optical fiber; a cooling device connected to a metal rod to transfer heat to the rod; and a ferrule having one side into which the optical fiber is inserted and the other side into which the rod is inserted, wherein the heat transferred to the rod is transferred to the quantum light source through the thermally conductive material.

Description

quantum light source device

[0001] The present disclosure generally relates to quantum light source devices.

[0002] Quantum dots and two-dimensional thin-film structures often operate at temperatures below 40 K or exhibit excellent performance at such temperatures. To utilize them, photons are collected using optical fibers.

[0003] Traditionally, signals provided by devices containing quantum light sources were captured in free space by a lens, forming a signal that was then transmitted via an optical fiber. However, to achieve superior performance, periodic optical alignment between the photon-providing quantum dots or quantum light source and the optical fiber is required.

[0004] Conventional techniques require cooling and alignment for operation. Furthermore, optical fibers are made of glass, making it difficult to lower temperatures due to their inherent properties.

[0005] One of the tasks to be solved by this embodiment is to overcome the difficulties of the above-described prior art.

[0006] A quantum light source device according to the present embodiment comprises: an optical fiber that transmits excitation light; a quantum light source provided with the excitation light to provide a quantum signal to the optical fiber and disposed at an end of the optical fiber; a thermally conductive material that coats the optical fiber; a cooling device that is connected to a metal rod and transmits heat to the rod; a ferrule into which the optical fiber is introduced at one end and into which the rod is introduced at the other end; and heat transmitted to the rod is transmitted to the quantum light source through the thermally conductive material.

[0007] According to one aspect of the present embodiment, the optical fiber includes a core and a cladding, the thermally conductive material coats the optical fiber so as to expose more than the entire core, and the quantum light source transmits a quantum signal through the exposed core.

[0008] According to one aspect of the present embodiment, the end of the rod facing the quantum light source is coated with a reflective member that reflects the quantum signal.

[0009] According to one aspect of the present embodiment, the quantum light source and the reflective member are spaced apart at a desired interval, and heat transferred to the load is transferred to the quantum light source device through the ferrule and the thermally conductive material.

[0010] According to one aspect of the present embodiment, one of a receiving groove for receiving the quantum light source and a hollow space for receiving the quantum light source is formed at the end of the rod, and the end of the optical fiber and the rod are in contact within the ferrule.

[0011] A quantum light source device according to the present embodiment includes: a first optical fiber that transmits excitation light; a quantum light source provided with the excitation light to output a quantum signal and disposed at an end of the first optical fiber; a thermally conductive material that coats the first optical fiber; a ferrule into which the first optical fiber is introduced at one end and into which a wavelength shift member is introduced at the other end; and a cooling device that is connected to the ferrule and transmits heat to the ferrule, wherein the heat transmitted to the ferrule is transmitted to the quantum light source through the thermally conductive material.

[0012] According to one aspect of the present embodiment, the thermally conductive material exposes more than the entire core, the optical fiber has a core having a first refractive index and a cladding having a second refractive index lower than the first refractive index, and the quantum light source transmits a quantum signal through the exposed core.

[0013] According to one aspect of the present embodiment, the wavelength shift member includes an electrode, an electric field forming surface connected to the electrode and formed at an end of the wavelength shift member to face the quantum light source, and an insulating member surrounding the electrode so that the electrode is exposed.

[0014] According to one aspect of the present embodiment, the wavelength shift member includes: a core; a cladding surrounding the core; an electrode; and a ring-shaped electric field forming surface connected to the electrode and formed at an end of the wavelength shift member so as to face the quantum light source and expose the core, wherein the cladding surrounds the electrode so as to expose the electrode.

[0015] According to one aspect of the present embodiment, the ferrule is a C-shaped ferrule including an opening through which the exposed electrode is exposed.

[0016] According to one aspect of the present embodiment, a reference voltage is applied to the ferrule, and a wavelength shift voltage is applied to the exposed electrode through the opening, thereby changing the wavelength of the quantum signal.

[0017] According to one aspect of the present embodiment, there is provided a quantum light source that outputs a quantum signal by providing the excitation light and is disposed at an end of the first optical fiber; a thermally conductive material that coats the first optical fiber; a second optical fiber into which the quantum signal is input; a ferrule into which the first optical fiber is introduced at one end and the second optical fiber is introduced at the other end; and a cooling device that is connected to the ferrule and transfers heat to the ferrule, wherein the heat transferred to the ferrule is transferred to the quantum light source through the thermally conductive material.

[0018] According to one aspect of the present embodiment, the first optical fiber includes a core and a cladding, the thermally conductive material coats the optical fiber so as to expose at least a portion of the core, and the quantum light source transmits a quantum signal through at least a portion of the exposed core.

[0019] According to one aspect of the present embodiment, the quantum light source provides the excitation light through the exposed core and transmits the quantum signal to the core of the second optical fiber.

[0020] According to one aspect of the present embodiment, an end of the second optical fiber facing the first optical fiber is formed with a receiving groove in which the quantum light source is received.

[0021] The quantum light source device of the present embodiment comprises: a mounting member having a plurality of V grooves formed therein and coated with a thermally conductive material; a cooling device for transferring heat to the mounting member; a plurality of optical fibers each mounted in the plurality of V grooves, at least a portion of which is coated with a thermally conductive material and transferring excitation light; quantum light sources positioned at each end of the optical fibers, each excited by the excitation light to form a quantum signal and providing the quantum signal to the optical fiber; and an electrode spaced apart from the quantum light sources, wherein a reference voltage is formed in the mounting member, and a wavelength shifting voltage is applied to the electrode to shift the wavelength of the quantum signal.

[0022] According to one aspect of the present embodiment, heat transferred to the mounting member is provided to the quantum light source through the thermally conductive material.

[0023] According to this embodiment, there is an advantage of ease of use as there is no need for periodic cooling and alignment.

[0024] Fig. 1 is a cross-sectional view illustrating an outline of a quantum light source device according to the first embodiment.

[0025] Figure 2 is a photograph showing a state in which a quantum light source is aligned and arranged on an optical fiber.

[0026] FIG. 3 is a drawing illustrating an outline of a quantum light source device according to another embodiment.

[0027] FIG. 4 is a diagram illustrating an outline of a quantum light source device according to another embodiment.

[0028] Fig. 5(a) is a drawing showing an example of the ferrule illustrated in Fig. 4, and Fig. 5(b) is a drawing showing an example of the wavelength variation member illustrated in Fig. 4.

[0029] Fig. 6(a) is a cross-sectional view of a wavelength variation member according to another example, and Fig. 6(b) is a drawing showing another example of a ferrule and a wavelength variation member.

[0030] Fig. 7 is a drawing for explaining a quantum light source device according to another embodiment.

[0031] Fig. 8 is a drawing for explaining a quantum light source device according to another embodiment.

[0032] Hereinafter, the present embodiment will be described with reference to the attached drawings.

[0033]

[0034] Example 1

[0035] FIG. 1 is a cross-sectional view illustrating an outline of a quantum light source device (10) according to a first embodiment. Referring to FIG. 1, the quantum light source device (10) includes an optical fiber (100) that transmits excitation light (E), a quantum light source (200) provided with the excitation light (E) to provide a quantum signal to the optical fiber (100) and arranged at an end of the optical fiber, a thermally conductive material (300) that coats the optical fiber, a cooling device (400) that is connected to a metal rod (410) and transmits heat to the metal rod (410), and a ferrule (500) into which the optical fiber is introduced on one side and into which the metal rod is introduced on the other side, and the heat transmitted to the metal rod is transmitted to the quantum light source (200) through the thermally conductive material (300).

[0036] An optical fiber (100) includes a core (110) having a first refractive index and a cladding (120) having a second refractive index. Excitation light (E) that excites a quantum light source (200) is provided through the core (110). In one embodiment, the excitation light may be O-band laser light. The quantum light source (200) is excited by the excitation light (E) to form and provide a quantum signal (Q), which is a single photon.

[0037] The end side of the illustrated optical fiber (100) is coated with a thermally conductive material (300). In one embodiment, the thermally conductive material (300) may be a light-shielding metal including any one of gold, silver, and copper. In one embodiment, the process of coating the end side of the optical fiber (100) with the thermally conductive material (300) may be performed through a deposition process such as plasma enhanced chemical vapor deposition (PECVD) or atomic layer deposition (ALD).

[0038] When the thermally conductive material (300) is a light-shielding metal, the excitation light (E) may not be transmitted to the quantum light source (200) or may be transmitted with an attenuation that is insufficient for exciting the quantum light source (200). In addition, the quantum signal (Q) provided by the quantum light source (200) may be blocked. Therefore, at least a portion of the thermally conductive material (300) is removed so that the core (110) is exposed. In one embodiment, the process of removing the thermally conductive material (300) so that the core (110) is exposed may be performed using a focused ion beam or laser etching.

[0039] Fig. 2 is a photograph illustrating a state in which a quantum light source (200) is aligned and positioned on an optical fiber (100). Referring to Figs. 1 and 2, the quantum light source (200) is aligned and positioned on an exposed core (110). In addition, a van der Waals force acts between the quantum light source (200) and a thermally conductive material (300), thereby attaching the quantum light source (200).

[0040] An optical fiber (100) having a quantum light source (200) is introduced into one end of a ferrule (500), and a rod (410) connected to a cooling device (400) is introduced into the other end. In one embodiment, the rod (410) may be made of a metal material having high thermal conductivity. The cooling device (400) cools the quantum light source (200) to a temperature sufficiently low for the quantum light source (200) to operate with excellent performance.

[0041] The heat transferred from the cooling device (400) to the metal rod (410) is transferred to the ferrule (500), as shown by the blue arrow, and to the thermally conductive material (300) of the optical fiber in contact with the ferrule (500). The quantum light source (200) is cooled to a sufficiently low temperature by the heat transferred to the thermally conductive material (300), and can generate a quantum signal (Q) with excellent performance. For example, the quantum light source (200) can be cooled to 40K or less.

[0042] The quantum light source (200) can form and provide a quantum signal (Q) in the direction in which the excitation light (E) is provided, and can form the quantum signal (Q) in the direction of the rod (410). The quantum light source (200) and the reflective member (412) can be spaced apart by a predetermined interval, and the quantum signal (Q) formed and provided in the direction of the rod (410) is reflected by the reflective member (412) located at the end of the rod (410) facing the optical fiber as illustrated, to form a standing wave (S), and is input in the direction in which the excitation light (E) is provided.

[0043] FIG. 3 is a drawing illustrating another embodiment. Referring to FIG. 3, a thermally conductive material (300) positioned at the end of an optical fiber (100) within a ferrule (500) can be cooled by direct contact with a rod (410) connected to a cooling device (400). A center hole (C) is formed in the rod (410) to accommodate a quantum light source (200). However, in an embodiment not illustrated, a groove may be formed in the rod to accommodate a quantum light source.

[0044]

[0045] Second Example

[0046] Hereinafter, a quantum light source (12) according to a second embodiment will be described with reference to FIGS. 4 to 6. However, for the sake of brevity and clarity, descriptions of elements identical or similar to those in the above-described embodiment may be omitted. Referring to FIG. 4, a quantum light source (12) according to the second embodiment includes: a first optical fiber (100) that transmits excitation light (E); a quantum light source (200) that is provided with the excitation light (E) to output a quantum signal (Q) and is disposed at an end of the first optical fiber; a thermally conductive material (300) that coats the first optical fiber; a ferrule (500) into which the first optical fiber (100) is introduced on one side and into which a wavelength variation member (600) is introduced on the other side; And it includes a cooling device (400) connected to the ferrule (500) and transferring heat to the ferrule (500), and the heat transferred to the ferrule (500) is transferred to the quantum light source (200) through the thermally conductive material (300).

[0047] The cooling member (400) is connected to the ferrule (500) to transfer heat to the ferrule (500) and cool the quantum light source (200) through the thermally conductive material (300) in contact with the ferrule (500). As a result, the quantum light source (200) can operate with high efficiency and form a quantum signal (Q).

[0048] FIG. 5(a) is a drawing illustrating an example of a ferrule (500) illustrated in FIG. 4, and FIG. 5(b) is a drawing illustrating an example of a wavelength shift member (600) illustrated in FIG. 4. Referring to FIGS. 4 and 5, the ferrule (500) is a C-shaped ferrule in which an opening (510) is formed, and the illustrated wavelength shift member (600) includes an electrode (610), an electric field forming surface (620) formed at an end of the wavelength shift member (600) and connected to the electrode (610) to form an electric field facing the quantum light source, and an insulating member (630) surrounding the electrode so that the electrode is exposed.

[0049] A reference voltage is applied to the ferrule (500). Accordingly, the conductive material (300) and cooling device (400) electrically connected to the ferrule (500) may also be applied with the reference voltage. For example, the reference voltage may be a ground voltage.

[0050] The electrode (610) included in the wavelength variation member (600) is exposed in the insulating member (630). In addition, the electrode (610) exposed in the insulating member (630) is exposed through the opening (510) of the ferrule (500) and a wavelength variation voltage is applied. Accordingly, an electric field is formed between the electric field forming surface (620) electrically connected to the electrode (610) and the thermally conductive material (300), and the wavelength of the quantum signal (Q) formed by the quantum light source is varied by the electric field. The quantum signal (Q) whose wavelength is varied is reflected and propagates to the core (110) of the optical fiber (100).

[0051] Fig. 6(a) is a cross-sectional view of a wavelength shift member according to another example, and Fig. 6(b) is a drawing illustrating another example of a ferrule and a wavelength shift member (600). Referring to Figs. 6(a) and 6(b), the wavelength shift member (600) includes a core (612), a cladding (622) surrounding the core (612), an electrode (610), and a ring-shaped electric field forming surface (620) connected to the electrode (610) and formed at an end of the wavelength shift member (610) to form an electric field facing a quantum light source, but exposing the core (610). In addition, the wavelength shift member (600) includes an insulating member (630) surrounding the electrode so that the electrode (610) is exposed.

[0052] A reference voltage is applied to the ferrule (500). Accordingly, the thermally conductive material (300) and the cooling device (400) electrically connected to the ferrule (500) can also be applied with the reference voltage. As illustrated, the electrode (610) is exposed from the insulating member (630) and through the opening (510) of the ferrule (500).

[0053] A wavelength-shifted voltage is applied to the exposed electrode (610), and a ring-shaped electric field-forming surface (620) connected to the electrode (610) forms an electric field with a thermally conductive material (350). The quantum signal (Q) formed by the quantum light source (200) is frequency-shifted by the electric field formed in this manner. The quantum signal with the frequency-shifted signal travels to the exposed core (612) through the ring-shaped electric field-forming surface (620).

[0054]

[0055] Third Example

[0056] Hereinafter, a quantum light source (14) according to a third embodiment will be described with reference to FIG. 7. However, for the sake of brevity and clarity, descriptions of elements identical or similar to those in the above-described embodiment may be omitted. Referring to FIG. 7, a quantum light source (14) according to the third embodiment includes: a first optical fiber (100) that transmits excitation light (E); a quantum light source (200) that is provided with the excitation light (E) to output a quantum signal (Q) and is disposed at an end of the first optical fiber (100); a thermally conductive material (300) that coats the first optical fiber (100); a second optical fiber (700) into which the quantum signal is input; a ferrule (500) into which the first optical fiber (100) is introduced on one side and the second optical fiber (700) is introduced on the other side; And it includes a cooling device (400) connected to the ferrule (500) and transferring heat to the ferrule, and the heat transferred to the ferrule is transferred to the quantum light source (200) through the thermally conductive material. The quantum signal (Q) generated by the quantum light source (200) is provided to the second optical fiber (700).

[0057] A first optical fiber (100) is introduced into one end of a ferrule (500), and a second optical fiber (700) is introduced into the other end. The first optical fiber (100) and the second optical fiber (700) introduced into the ferrule (500) are aligned with each other, so there is no need to perform repetitive work of alignment after cooling as in the prior art, which is efficient.

[0058] In an embodiment not shown, the end of the second optical fiber facing the quantum light source includes a groove formed by removing the core and cladding of the second optical fiber. When the first and second optical fibers are adjacent, the quantum light source is accommodated in the groove to generate a quantum signal, and the generated quantum signal can be transmitted to the core of the second optical fiber.

[0059]

[0060] Example 4

[0061] Hereinafter, a quantum light source (16) according to a fourth embodiment will be described with reference to FIG. 8. However, for the sake of brevity and clarity, descriptions of elements identical or similar to those in the above-described embodiment may be omitted. Referring to FIG. 7, a quantum light source (16) according to the fourth embodiment includes: a mounting member (810) having a plurality of V grooves formed therein and coated with a thermally conductive material; a cooling device (400) for transferring heat to the mounting member (810); a plurality of optical fibers (100) each mounted in the plurality of V grooves, at least part of which is coated with a thermally conductive material and transfers excitation light; quantum light sources (200) positioned at each end of the optical fibers, each excited by the excitation light to form a quantum signal and provide the quantum signal to the optical fibers; It includes an electrode (820) spaced apart from the quantum light sources, a reference voltage is provided to the fixing member (810), and a wavelength shifting voltage is applied to the electrode (820) to shift the wavelength of the quantum signal.

[0062] In the illustrated embodiment, a plurality of optical fibers are arranged in a V-groove. A cooling device (400) cools the mounting member (810), and heat is transferred to the mounting member (810) and the thermally conductive material (300), thereby cooling the quantum light source (200) and generating a quantum signal (Q).

[0063] A reference voltage is provided to the fixing member (810), and the reference voltage is also applied to the thermally conductive material (300). The electrodes (820) are positioned spaced apart from the ends of the optical fibers (100). The number of electrodes (820) may correspond to the number of optical fibers (100), and are spaced apart to correspond to the position of the quantum light source (200). A wavelength shift voltage may be applied to each of the electrodes (820), and an electric field is formed between the electrodes (820) and the thermally conductive material (300) to which the reference voltage is applied by the wavelength shift voltage.

[0064] Accordingly, the wavelength of the quantum signal (Q) formed by the quantum light sources (200) is changed to correspond to the wavelength variation electric field described above and propagates through the core of the optical fiber.

[0065]

[0066] While the present invention has been described with reference to the embodiments illustrated in the drawings to aid understanding, these are merely exemplary embodiments for practical purposes. Those skilled in the art will understand that various modifications and equivalent alternative embodiments are possible. Therefore, the true technical protection scope of the present invention should be defined by the appended claims.

Claims

1. An optical fiber that transmits excitation light; A quantum light source provided with the above-described excitation light to provide a quantum signal to the optical fiber, and arranged at an end of the optical fiber; A thermally conductive material coating the optical fiber; A cooling device connected to a metal rod and transferring heat to the rod; A ferrule into which the optical fiber is introduced on one side and the load is introduced on the other side; and A quantum light source device in which heat transferred to the above load is transferred to the quantum light source through the above thermally conductive material.

2. In paragraph 1, The above optical fiber, Contains a core and cladding, The thermally conductive material coats the optical fiber so as to expose at least a portion of the core; The above quantum light source is a quantum light source device that transmits quantum signals through the exposed core.

3. In paragraph 1, At the end of the above rod facing the above quantum light source, A reflective member that reflects the above quantum signal is coated, A quantum light source device in which the quantum light source and the reflective member are spaced apart by a desired interval.

4. In paragraph 1, A quantum light source device in which heat transferred to the above load is transferred to the quantum light source device through the ferrule and the thermally conductive material.

5. In paragraph 1, At the end of the above load One of a storage groove in which the quantum light source is stored and a cavity in which the quantum light source is stored is formed, A quantum light source device in which the above load contacts the end of the optical fiber and the ferrule to transfer heat to the quantum light source.

6. A first optical fiber transmitting excitation light; A quantum light source provided with the above excitation light to output a quantum signal and arranged at the end of the first optical fiber; A thermally conductive material coating the first optical fiber; A ferrule into which the first optical fiber is introduced on one side and into which a wavelength shift member is introduced on the other side; and A cooling device is included that is connected to the above ferrule and transfers heat to the ferrule, A quantum light source device in which heat transferred to the above ferrule is transferred to the quantum light source through the above thermally conductive material.

7. In paragraph 6, The thermally conductive material exposes at least a portion of the core, The optical fiber has a core having a first refractive index and a cladding having a second refractive index lower than the first refractive index. The above quantum light source is a quantum light source device that transmits a quantum signal through the exposed core.

8. In paragraph 6, The absence of the above wavelength variation A quantum light source device comprising an electrode, an electric field forming surface formed at an end of the wavelength shift member and connected to the electrode, the electric field forming surface facing the quantum light source, and an insulating member surrounding the electrode so that the electrode is exposed.

9. In paragraph 6, The absence of the above wavelength variation is core; Cladding surrounding the above core; electrode; It includes a ring-shaped electric field forming surface connected to the electrode and formed at an end of the wavelength variation member, facing the quantum light source and exposing the core, A quantum light source device in which the cladding surrounds the electrode so that the electrode is exposed.

10. In either of paragraphs 8 and 9, The above ferrule is a C-shaped ferrule including an opening, A quantum light source device in which the exposed electrode is exposed through the opening.

11. In either of paragraphs 8 and 9, A reference voltage is applied to the above ferrule, A quantum light source device in which a wavelength-shifting voltage is applied to the exposed electrode through the opening, thereby changing the wavelength of the quantum signal.

12. A first optical fiber transmitting excitation light; A quantum light source provided with the above excitation light to output a quantum signal and arranged at the end of the first optical fiber; A thermally conductive material coating the first optical fiber; A second optical fiber into which the quantum signal is input; A ferrule into which the first optical fiber is introduced on one side and the second optical fiber is introduced on the other side; and A cooling device is included that is connected to the above ferrule and transfers heat to the ferrule, A quantum light source device in which heat transferred to the above ferrule is transferred to the quantum light source through the above thermally conductive material.

13. In paragraph 12, The above first optical fiber, Contains a core and cladding, The thermally conductive material coats the optical fiber so as to expose at least a portion of the core; A quantum light source device that transmits quantum signals through at least a portion of the exposed core.

14. In paragraph 13, The above quantum light source is, The excitation light is provided through the exposed core, A quantum light source device that transmits the quantum signal to the core of the second optical fiber.

15. In paragraph 12, The end of the second optical fiber facing the first optical fiber A quantum light source device in which a storage groove is formed to store the quantum light source.

16. A mounting member having a plurality of V grooves formed therein and coated with a thermally conductive material; A cooling device for transferring heat to the above-mentioned fixing member; A plurality of optical fibers each mounted in the plurality of V grooves, at least part of which is coated with a thermally conductive material and transmitting excitation light; Quantum light sources positioned at each end of the optical fibers and excited by the excitation light to form quantum signals and provide them to the optical fibers; comprising electrodes spaced apart from the above quantum light sources, A quantum light source device in which a reference voltage is formed in the above-mentioned stabilizing member and a wavelength shifting voltage is applied to the above-mentioned electrode to shift the wavelength of the quantum signal.

17. In paragraph 16, A quantum light source device in which heat transferred to the above-mentioned stabilizing member is provided to the quantum light source through the above-mentioned thermally conductive material.

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