阅读说明：本技术 一种超导探测器 (Superconducting detector ) 是由 王钊 郭伟杰 于 2021-06-02 设计创作，主要内容包括：本申请实施例提供一种超导探测器,所述超导探测器包括：衬底,以及设置于所述衬底上的介质层；超导线结构,包括多层堆叠设置的超导线层,每层所述超导线层由一根超导线在同一平面内形成,相邻的两层所述超导线层交错排布,相邻的两层所述超导线层之间通过所述介质层隔开。本申请实现了提高光敏区有效面积,降低光纤对准难度。(An embodiment of the present application provides a superconducting probe, including: the dielectric layer is arranged on the substrate; the superconducting wire structure comprises a plurality of superconducting wire layers which are stacked, each superconducting wire layer is formed by one superconducting wire in the same plane, two adjacent superconducting wire layers are arranged in a staggered mode, and the two adjacent superconducting wire layers are separated through a dielectric layer. This application has realized improving photosensitive area effective area, reduces the optic fibre and aims at the degree of difficulty.)

1. A superconducting probe, comprising:

the dielectric layer is arranged on the substrate;

the superconducting wire structure comprises a plurality of superconducting wire layers which are stacked, each superconducting wire layer is formed by one superconducting wire in the same plane, two adjacent superconducting wire layers are arranged in a staggered mode, and the two adjacent superconducting wire layers are separated through a dielectric layer.

2. The superconducting probe of claim 1, wherein the superconducting probe includes a plurality of the dielectric layers, the superconducting probe further comprising:

the first reflecting structure comprises a first reflecting layer and a second reflecting layer, the first reflecting layer is arranged on the outer surface of the outermost dielectric layer, and the second reflecting layer is arranged between the substrate and the superconducting line structure.

3. The superconducting probe of claim 1, further comprising:

and the second reflecting structure is arranged between the substrate and the dielectric layer.

4. The superconducting probe of claim 1, further comprising:

and the capacitance regions are arranged on the upper surface of the dielectric layer and positioned at two sides of the superconducting line structure.

5. The superconducting probe of claim 1, wherein two adjacent superconducting wire layers are connected in parallel or in series through a metal via.

6. The superconducting probe of claim 1, wherein the dielectric layer is made of one of alpha silicon, silicon oxide, silicon nitride, magnesium fluoride and titanium oxide.

7. A superconducting probe according to claim 1 wherein the superconducting wire structure has a duty cycle which is adjustable up to 100%.

8. The superconducting probe of claim 1, wherein the bent shape of the superconducting wire is a zigzag shape or a spiral shape.

9. The superconducting probe of claim 1, wherein the superconducting wire is a superconducting nanowire or a superconducting microwire.

10. The superconducting probe of claim 1, wherein each of the superconducting wire layers has a single layer thickness that is equal, and wherein the single layer thickness of the superconducting wire layer decreases with an increase in the total length of the superconducting wire and decreases with an increase in the line width of the superconducting wire.

11. The superconducting probe of claim 1, wherein each of the superconducting wire layers is formed by bending a superconducting wire in a same plane.

Technical Field

The application relates to the technical field of optical detection, in particular to a superconducting detector.

Background

In recent years, optical quantum information technology is rapidly developed, a basic carrier of information is a single photon which is not easily interfered, conventional detectors such as a traditional avalanche diode and a photomultiplier cannot meet the application requirements of people in the fields of quantum optics, precision measurement and the like, and a superconducting single photon detector working in a communication waveband is required for accurately reading photon information, for example: superconducting transition edge detectors (TES), microwave dynamic inductance detectors (MKID), Superconducting Nanowire Single Photon Detectors (SNSPD), and the like.

When the superconducting detector is used for detection, the optical fiber for conducting photons needs to be accurately aligned to the superconducting wire in the photosensitive region of the superconducting detector, so that the photons fall on the superconducting wire as far as possible, and the detection efficiency of the detector is ensured. The area of the photosensitive region of a superconducting detector is usually small, wherein the linewidth of a superconducting wire generally ranges from tens of nanometers to several micrometers, and a certain duty cycle exists.

In the prior art, a commonly used alignment technique for superconducting detectors is the self-alignment technique of NIST (National Institute of Standards and Technology ), which keeps the size of the sample chamber circular hole for placing the detector chip consistent with the inner diameter of the optical fiber sleeve, so that the optical fiber sleeve can be perfectly clamped into the sample chamber.

Disclosure of Invention

An object of the embodiments of the present application is to provide a superconducting detector for increasing an effective area of a photosensitive region and reducing difficulty in aligning an optical fiber.

A first aspect of embodiments of the present application provides a superconducting probe, including: the dielectric layer is arranged on the substrate; the superconducting wire structure comprises a plurality of superconducting wire layers which are stacked, each superconducting wire layer is formed by one superconducting wire in the same plane, two adjacent superconducting wire layers are arranged in a staggered mode, and the two adjacent superconducting wire layers are separated through a dielectric layer.

In one embodiment, the superconducting probe includes a plurality of dielectric layers, and the superconducting probe further includes: the first reflecting structure comprises a first reflecting layer and a second reflecting layer, the first reflecting layer is arranged on the outer surface of the outermost dielectric layer, and the second reflecting layer is arranged between the substrate and the superconducting line structure.

In one embodiment, the superconducting probe further includes: and the second reflecting structure is arranged between the substrate and the dielectric layer.

In one embodiment, the superconducting probe further includes: and the capacitance regions are arranged on the upper surface of the dielectric layer and positioned at two sides of the superconducting line structure.

In one embodiment, two adjacent layers of the super conductor layer are connected in parallel or in series through the metal via.

In an embodiment, the dielectric layer is made of one of α -silicon, silicon oxide, silicon nitride, magnesium fluoride, and titanium oxide.

In one embodiment, the duty cycle of the superconducting wire structure is adjustable, up to 100%.

In one embodiment, the bent shape of the superconducting wire is a zigzag shape or a spiral shape.

In one embodiment, the superconducting wire is a superconducting nanowire or a superconducting microwire.

In one embodiment, the individual thicknesses of the superconducting wire layers are equal, and the individual thicknesses of the superconducting wire layers decrease with the increase of the total length of the superconducting wire and decrease with the increase of the line width of the superconducting wire.

In one embodiment, each superconducting wire layer is formed by bending a superconducting wire in the same plane.

The high-efficiency collection of detected light can be realized, the adjustable detection efficiency can be realized, and the highest effective detection area is 100%. Meanwhile, the alignment difficulty and the processing precision requirement of the optical fiber are reduced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments of the present application will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that those skilled in the art can also obtain other related drawings based on the drawings without inventive efforts.

FIG. 1 is a schematic cross-sectional view of a superconducting probe according to an embodiment of the present application;

FIG. 2 is a schematic cross-sectional view of a superconducting probe according to an embodiment of the present application;

FIG. 3 is a schematic diagram of a super conductor layer according to an embodiment of the present application;

FIG. 4 is a schematic cross-sectional view of a superconducting probe according to an embodiment of the present application;

FIG. 5 is a schematic cross-sectional view of a superconducting probe according to an embodiment of the present application;

FIG. 6 is a schematic cross-sectional view of a superconducting probe according to an embodiment of the present application;

FIG. 7 is a schematic diagram of a super-conductive line layer according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a super-conductor layer according to an embodiment of the present application;

FIG. 9 is a schematic view of a superconducting wire structure according to an embodiment of the present application;

FIG. 10 is a schematic view of a superconducting wire structure according to an embodiment of the present application;

fig. 11 is a schematic diagram of a superconducting wire structure according to an embodiment of the present application.

Reference numerals:

100-a superconducting detector, 110-a substrate, 120-a dielectric layer, 130-a superconducting line structure, 131-a superconducting line layer, 140-a capacitance area, 150-a first reflection structure, 151-a first reflection layer, 152-a second reflection layer, 160-a second reflection structure, 161-a third reflection layer, 162-a fourth reflection layer and 170-an antireflection film.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application.

In the description of the present application, the terms "first," "second," and the like are used for distinguishing between descriptions and do not denote an order of magnitude, nor are they to be construed as indicating or implying relative importance.

In the description of the present application, the terms "comprises," "comprising," and/or the like, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof.

In the description of the present application, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are absolutely required to be horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present application, the terms "upper", "lower", "left", "right", "front", "back", "inner", "outer", and the like refer to orientations or positional relationships that are based on orientations or positional relationships shown in the drawings, or orientations or positional relationships that are conventionally found in the products of the application, and are used for convenience in describing the present application, and do not indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, should not be construed as limiting the present application.

In the description of the present application, the terms "mounted," "disposed," "provided," "connected," and "configured" are to be construed broadly unless expressly stated or limited otherwise. For example, it may be a fixed connection, a removable connection, or a unitary construction; can be mechanically or electrically connected; either directly or indirectly through intervening media, or may be internal to two devices, elements or components. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

Please refer to fig. 1, which is a schematic cross-sectional structure diagram of a superconducting probe 100 according to an embodiment of the present application. The superconducting probe 100 includes: substrate 110, dielectric layer 120 and superconducting wire structure 130, dielectric layer 120 sets up on substrate 110, superconducting wire structure 130 includes the superconductive wire layer 131 that the multilayer piles up and sets up, takes two layers of superconductive wire layer 131 as the example in fig. 1, and each layer of superconductive wire layer 131 is formed by a superconductive line in the coplanar, and two adjacent layers of superconductive wire layer 131 are crisscross to be arranged, and two adjacent layers of superconductive wire layer 131 are separated through dielectric layer 120.

The dielectric layer 120 has no absorption to photons to be measured and has an insulating effect, and in an embodiment, the dielectric layer 120 is made of alpha silicon (alpha-Si) or silicon oxide (SiO)₂) Silicon nitride (SiN), magnesium fluoride (MgF), titanium oxide (TiO)₂) One kind of (1).

In one embodiment, each superconducting wire layer may be formed by bending one superconducting wire in the same plane. Each superconducting wire layer may be a single linear superconducting wire.

In one embodiment, the substrate 110 is made of silicon or sapphire.

In one embodiment, the superconducting wire may be made of NbN, Al, TiN, NbTiN, PtSi, or other superconducting materials.

In one embodiment, two adjacent super-conductive wire layers 131 are connected by metal vias. The metal via hole can realize the conductive communication between two adjacent superconducting wire layers 131, and can also span the multi-layer superconducting wire layers 131 and the dielectric layer 120 to realize the conductive communication between the non-adjacent superconducting wire layers 131.

In an embodiment, two adjacent super-conductive wire layers 131 may be connected in parallel or in series. As shown in fig. 1, the two superconducting wire layers 131 are connected in parallel with each other, and as shown in fig. 2, the two superconducting wire layers 131 are connected in series with each other.

In one embodiment, the superconducting wire layer 131 has a zigzag or spiral shape, and the superconducting wire is a superconducting nanowire or a superconducting nanowire.

In one embodiment, the duty cycle of superconducting wire structure 130 may be adjusted to a maximum of 100%.

In an embodiment, the bending shapes of the superconducting wires in the first layer of superconducting wire layer 131 and the second layer of superconducting wire layer 131 may be both zigzag, the superconducting wires with uniform wire widths are bent at equal intervals, and the wire widths and the intervals of the superconducting wires are equal (as shown in fig. 3), the upper layer of superconducting wire layer 131 and the lower layer of superconducting wire layer 131 are arranged in a staggered manner, and the distance of one wire width is staggered with respect to each other, that is, the superconducting wires in the first layer of superconducting wire layer 131 correspond to the gap region in the second layer of superconducting wire layer 131, photons to be detected are incident from top to bottom, and when viewed from the incident direction of the photons to be detected, the gap region is filled with each other by the first layer of superconducting wire layer 131 and the second layer of superconducting wire layer 131, so that 100% coverage of the superconducting wires in the photosensitive region is achieved. When light is aligned, only the photon is required to be focused in the range of the photosensitive region, the alignment to a single superconducting wire is not required, the line width of the superconducting wire is generally different from dozens of nanometers to several micrometers, the size of the photosensitive region is generally dozens of micrometers, the alignment precision requirement is reduced from the line width of the single superconducting wire to the whole area of the photosensitive region, and the alignment difficulty of the optical fiber is greatly reduced.

In one embodiment, the duty cycle of superconducting wire structure 130 can be adjusted by adjusting the offset distance between different superconducting wire layers 131, or the width of the superconducting wire on different layers, such that the superconducting wire layers 131 are partially overlapped or exactly staggered and complementary.

In one embodiment, the individual thicknesses of each superconducting wire layer 131 are equal, and the individual thicknesses of the superconducting wire layers 131 decrease with increasing total length of the superconducting wire and decrease with increasing line width of the superconducting wire.

In one embodiment, superconducting wire structure 130 has a constant total volume of superconducting wire, and as the number of layers of superconducting wire layer 131 increases, the thickness of each layer of superconducting wire layer 131 decreases.

In one embodiment, the superconducting wires may be non-uniform width superconducting wires, and the individual thicknesses of each layer of superconducting wire layer 131 may also be different, and if the number of layers of superconducting wire layer 131 is increased, the individual thickness of each layer of superconducting wire layer 131 may be correspondingly decreased to keep the total volume of the superconducting wires of superconducting wire structure 130 constant.

In one embodiment, the length of the superconducting wire is 20um, and the width of the superconducting wire is 2um, and the length and the width of the superconducting wire can be adjusted according to actual conditions.

In one embodiment, the superconducting probe 100 further includes: capacitor region 140, capacitor region 140 is disposed on the upper surface of dielectric layer 120 and on both sides of superconducting wire structure 130.

The photon to be detected can be effectively detected only by irradiating the superconducting wire, a certain duty ratio exists in the design of the superconducting wire in the light sensitive area which is used more at present, the photon to be detected is required to be focused in the line width range of the superconducting wire accurately, the line width of the superconducting wire is narrow, the large-scale accurate alignment difficulty is extremely high at low temperature, the superconducting wire layer 131 which is arranged in a staggered mode is used for achieving the maximum superconducting wire duty ratio of 100% in the limited light sensitive area, the effective area in the light sensitive area is increased, and therefore the difficulty of optical fiber alignment is reduced.

Fig. 4 is a schematic cross-sectional view of a superconducting probe 100 according to an embodiment of the present invention. The superconducting probe 100 includes: the superconducting wire structure 130 comprises a plurality of superconducting wire layers 131 which are stacked, three superconducting wire layers 131 are taken as an example in fig. 4, each superconducting wire layer 131 is formed by bending a superconducting wire in the same plane, two adjacent superconducting wire layers 131 are arranged in a staggered mode, and the two adjacent superconducting wire layers 131 are separated from each other through the dielectric layer 120.

The first reflective structure 150 includes a first reflective layer 151 and a second reflective layer 152, the first reflective layer 151 being disposed on an outer surface of the outermost dielectric layer 120, and the second reflective layer 152 being disposed between the substrate 110 and the superconducting wire structure 130.

In one embodiment, the first reflective layer 151 may be one of Au, Ag, and Al, and the second reflective layer 152 may be silicon oxide or silicon nitride or alpha silicon, magnesium fluoride, and titanium oxide. The first reflective layer 151 and the second reflective layer 152 may form a FP (Fabry-perot) cavity, which further improves the photon detection efficiency.

In an embodiment, the superconducting detector further includes an anti-reflection film 170, the anti-reflection film 170 is disposed on a surface of the substrate 110 opposite to the superconducting line structure 130, and the photons to be measured enter from bottom to top and pass through the anti-reflection film 170 before entering the substrate 110. In one embodiment, the anti-reflection film 170 may be silicon oxide or silicon nitride or alpha silicon, magnesium fluoride, titanium oxide.

Fig. 5 is a schematic cross-sectional view of a superconducting probe 100 according to an embodiment of the present invention. The superconducting probe 100 includes: the superconducting wire structure 130 comprises a plurality of superconducting wire layers 131 which are stacked, three superconducting wire layers 131 are taken as an example in fig. 4, each superconducting wire layer 131 is formed by bending a superconducting wire in the same plane, two adjacent superconducting wire layers 131 are arranged in a staggered mode, and the two adjacent superconducting wire layers 131 are separated from each other through the dielectric layer 120. And a second reflective structure 160 disposed between substrate 110 and dielectric layer 120.

In one embodiment, the second reflective structure 160 is one of Au, Ag, and Al, and the photons to be measured are incident from top to bottom.

Fig. 6 is a schematic cross-sectional view of a superconducting probe 100 according to an embodiment of the present invention. The superconducting probe 100 includes: the superconducting wire structure 130 comprises a plurality of superconducting wire layers 131 which are stacked, three superconducting wire layers 131 are taken as an example in fig. 4, each superconducting wire layer 131 is formed by bending a superconducting wire in the same plane, two adjacent superconducting wire layers 131 are arranged in a staggered mode, and the two adjacent superconducting wire layers 131 are separated from each other through the dielectric layer 120. And a second reflective structure 160 disposed between substrate 110 and dielectric layer 120.

In one embodiment, the second reflective structure 160 is a Distributed Bragg Reflector (DBR), and the photons to be measured are incident from top to bottom. The second reflective structure 160 includes a third reflective layer 161 and a fourth reflective layer 162, the third reflective layer 161 and the fourth reflective layer 162 are alternately stacked, the third reflective layer 161 may be silicon oxide or silicon nitride or alpha-silicon, magnesium fluoride, titanium oxide, and the fourth reflective layer 162 may be Ta₂O₅。

As shown in fig. 7, which is a schematic structural diagram of superconducting wire layer 131 according to an embodiment of the present application, a bent shape of the superconducting wire in superconducting wire layer 131 is a square spiral. Referring to fig. 8, which is a schematic view of a superconducting wire layer 131 according to another embodiment of the present application, a bent shape of a superconducting wire in the superconducting wire layer 131 is a circular spiral.

As shown in fig. 9, which is a schematic diagram of a superconducting wire structure 130 according to an embodiment of the present application, the superconducting wire structure 130 includes two superconducting wire layers 131, the two superconducting wire layers 131 are stacked in sequence from bottom to top at intervals, the two superconducting wire layers 131 are in a circular spiral structure with the same direction, and centers of the two superconducting wire layers 131 are electrically connected through a metal via. The two superconducting wire layers 131 have different spiral densities and are arranged in a staggered manner, and the superconducting wires in the first superconducting wire layer 131 correspond to the gap regions in the second superconducting wire layer 131.

As shown in fig. 10, which is a schematic diagram of a superconducting wire structure 130 according to an embodiment of the present application, the superconducting wire structure 130 includes two superconducting wire layers 131, the two superconducting wire layers 131 are stacked in sequence from bottom to top at intervals, the two superconducting wire layers 131 are in an inverted circular spiral structure, the two superconducting wire layers 131 are arranged in a staggered manner, and centers of the two superconducting wire layers 131 are electrically connected through metal vias.

As shown in fig. 11, which is a schematic diagram of a superconducting wire structure 130 according to an embodiment of the present disclosure, the superconducting wire structure 130 includes three superconducting wire layers 131, the three superconducting wire layers 131 are stacked in sequence from bottom to top at intervals, the first superconducting wire layer 131 and the third superconducting wire layer 131 are circular spiral structures in the same direction, the first superconducting wire layer 131 and the third superconducting wire layer 131 have different spiral densities and the same spiral direction, and are arranged in a staggered manner, and superconducting wires in the first superconducting wire layer 131 correspond to gap regions in the third superconducting wire layer 131. One side terminal of the second super conductor layer 131 is connected to the outer terminal of the first super conductor layer 131, the other side terminal of the second super conductor layer 131 is connected to the center of the third super conductor layer 131, and current can flow in the same direction in the first super conductor layer 131 and the third super conductor layer 131.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. The above description is only a preferred embodiment of the present application, and is only for the purpose of illustrating the technical solutions of the present application, and not for the purpose of limiting the present application. Any modification, equivalent replacement, improvement or the like, which would be obvious to one of ordinary skill in the art and would be within the spirit and principle of the present application, should be included within the scope of the present application.