JP2715320B2 - Photodetector - Google Patents
PhotodetectorInfo
- Publication number
- JP2715320B2 JP2715320B2 JP1192528A JP19252889A JP2715320B2 JP 2715320 B2 JP2715320 B2 JP 2715320B2 JP 1192528 A JP1192528 A JP 1192528A JP 19252889 A JP19252889 A JP 19252889A JP 2715320 B2 JP2715320 B2 JP 2715320B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- magnetic field
- photodetector
- squid
- light receiving
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Landscapes
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、超伝導体の量子干渉効果を利用して、入力
光を電流に変換したのち、磁気信号に変換して、信号を
検出する光検出素子に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention converts an input light into a current using a quantum interference effect of a superconductor, and then converts the input light into a magnetic signal to detect a signal. It relates to a light detection element.
［従来の技術］ 従来の超伝導体を用いた信号検出素子、特に光信号を
検出する素子としては、ジョセフソン接合を利用したも
のが知られている［Japanese Journal of Applied Phys
ics vol.23 L333（1984）］。この光信号検出素子は、
第４図に示すように、酸化物超伝導体BaPb0.7Bi0.3O
3（BPBO）薄膜でマイクロブリッジ型ジョセフソン接合
を形成し、この接合部に光を照射し、ジョセフソン接合
の臨界電流値の変化を利用するものである。かかる検出
素子においては、受光部の材料としてBPBOを用いてお
り、これは臨界温度が約13Kと低い。すなわち、検出素
子を動作させるには、液体ヘリウム等を使用しなければ
ならない。また、かかる検出素子の特性は、ジョセフソ
ン接合の特性によって決定される。[Prior Art] As a signal detecting element using a conventional superconductor, in particular, an element using a Josephson junction is known as an element for detecting an optical signal [Japanese Journal of Applied Physics].
ics vol.23 L333 (1984)]. This optical signal detection element
As shown in FIG. 4, the oxide superconductor BaPb 0.7 Bi 0.3 O
3 (BPBO) A microbridge-type Josephson junction is formed from a thin film, and this junction is irradiated with light to utilize the change in the critical current value of the Josephson junction. In such a detecting element, BPBO is used as a material of the light receiving section, and its critical temperature is as low as about 13K. That is, in order to operate the detection element, liquid helium or the like must be used. Further, the characteristics of the detection element are determined by the characteristics of the Josephson junction.
［発明が解決しようとする課題］ 上記従来例においては、ジョセフソン接合部の臨界電
流が十分に変化する程度の光量が必要となるが、それが
難しく素子の感度は悪くなっていた。[Problems to be Solved by the Invention] In the above-mentioned conventional example, a light amount is required to such an extent that the critical current of the Josephson junction changes sufficiently, but this is difficult and the sensitivity of the device is deteriorated.
また、受光部と検出部が同一のジョセフソン接合であ
るため、特性のバラツキが出る問題があった。In addition, since the light receiving section and the detecting section are the same Josephson junction, there is a problem in that the characteristics vary.
さらに、超伝導体の分光特性により、検出する光の波
長域も限定されるため、広範囲の波長帯域の信号検出に
適していないという問題もあった。Furthermore, since the wavelength range of light to be detected is limited by the spectral characteristics of the superconductor, there is a problem that it is not suitable for signal detection in a wide wavelength band.
すなわち、本発明の目的とするところは、受光部と検
出部を別個のものとし、さらに超伝導物質の量子干渉効
果を利用することにより、上述のような問題点を解決す
ることにある。That is, an object of the present invention is to solve the above-mentioned problems by making the light receiving unit and the detecting unit separate and utilizing the quantum interference effect of a superconducting substance.
［課題を解決するための手段］ 本発明の特徴とするところは、光入射により電流を生
じる受光部と、該電流に相当する磁場を発生させる配線
と、かかる配線部に生じた磁場を検出する超伝導量子干
渉計を有する検出部とを少なくとも有する光検出素子に
ある。[Means for Solving the Problems] The present invention is characterized in that a light-receiving section that generates a current by light incidence, a wiring that generates a magnetic field corresponding to the current, and a magnetic field generated in the wiring section are detected. And a detection unit having a superconducting quantum interferometer.
また、前記磁場発生用配線として光導電材料を用いた
光検出素子にある。The present invention also provides a photodetector using a photoconductive material as the magnetic field generating wiring.
すなわち、単結晶又は多結晶超伝導材料等を用いた超
伝導量子干渉素子に、受光部で発生した電流によって生
じる磁気を導入することにより達成される。That is, it is achieved by introducing magnetism generated by a current generated in the light receiving unit into a superconducting quantum interference device using a single crystal or polycrystalline superconducting material.
ここで、本発明を達成するために用いられる超伝導材
料としては、超伝導特性を有する材料であれば何でもよ
いが、検出素子をより高い温度で動作させるために、臨
界温度の高い材料が好ましい。この点でＹ−Ba−Cu−Ｏ
系、Bi−Sr−Ca−Cu−Ｏ系、Tl−Ba−Ca−Cu−Ｏ系セラ
ミックス材料のような液体窒素の沸点である77Kより高
い臨界温度を持つ物質が適している。Here, as the superconducting material used to achieve the present invention, any material having superconducting properties may be used, but in order to operate the detecting element at a higher temperature, a material having a high critical temperature is preferable. . In this regard, Y-Ba-Cu-O
A material having a critical temperature higher than the boiling point of liquid nitrogen, 77 K, such as a ceramic material, a Bi-Sr-Ca-Cu-O-based ceramic material, or a Tl-Ba-Ca-Cu-O-based ceramic material is suitable.
また、受光部に用いる材料は、光入射により電流が生
じるものであれば何でも良いが、赤外，可視，紫外光の
ような光信号に対しては、光導電性材料を用いることが
望ましい。Further, the material used for the light receiving portion may be any material as long as a current is generated by light incidence. However, it is desirable to use a photoconductive material for optical signals such as infrared, visible, and ultraviolet light.
特に、大きな光電流を生じる光導電性材料としては、
InSbn,Si,GaAs,a−Si,CdS,CdSe等が好ましい。In particular, as a photoconductive material that generates a large photocurrent,
InSbn, Si, GaAs, a-Si, CdS, CdSe and the like are preferable.
この他、光電流を発生させるのに光電子倍増管，光起
電力効果，デンバー効果等を用いたものが考えられる。In addition, a photomultiplier, a photovoltaic effect, a Denver effect, or the like may be used to generate a photocurrent.
一方、前記検出部としては、超伝導リング内の磁束が
量子化される現象を用いた超伝導量子干渉素子（SQUI
D）を用いる。かかるSQUIDのタイプとしては、DC SQUID
又はRF SQUIDのどちらを用いてもかまわない。On the other hand, as the detection unit, a superconducting quantum interference device (SQUI) using a phenomenon in which magnetic flux in a superconducting ring is quantized is used.
Use D). Such SQUID types include DC SQUID
Alternatively, either RF SQUID may be used.
また、受光部をかかるSQUIDから離して設計しても、S
QUID上部又は隣に設計してもかまわない。さらには、配
線自身を受光部にすることも可能である。例えば、光導
電材料を用いSQUID上に磁場をつくる様配線することが
可能である。また、この配線を超伝導体にして磁場発生
効率を上げることも可能である。また、受光部の感度を
上げるために、受光部のみを加熱する小型ヒーターを取
り付けることも考えられる。さらに、本発明の素子を１
次元的に、もしくは２次元的に並べ、集積化することも
可能である。この場合、各々が光に対するラインセンサ
ー，平面型センサーとなる。本発明に係る素子では、検
出部にSQUIDを用いているため、超高感度の光センサー
が得られ、この素子を用いた分光器等のシステムも可能
である。Also, even if the light receiving unit is designed away from such SQUID,
It may be designed above or next to the QUID. Further, the wiring itself can be used as the light receiving section. For example, wiring can be performed using a photoconductive material to create a magnetic field on the SQUID. It is also possible to use this wiring as a superconductor to increase the magnetic field generation efficiency. Further, in order to increase the sensitivity of the light receiving unit, it is conceivable to attach a small heater for heating only the light receiving unit. Further, the device of the present invention is
It is also possible to arrange and integrate two-dimensionally or two-dimensionally. In this case, each becomes a line sensor and a flat sensor for light. In the element according to the present invention, since the SQUID is used for the detection unit, an optical sensor with ultra-high sensitivity can be obtained, and a system such as a spectroscope using this element is also possible.
［作 用］ 例えば、光導電性材料より成る受光部に光を照射する
と、価電子帯の電子は励起され伝導帯に遷移する。この
伝導帯中で励起された電子が印加された電場により移動
することで光電流が生ずる。[Operation] For example, when light is irradiated on a light receiving portion made of a photoconductive material, electrons in the valence band are excited and transit to the conduction band. A photocurrent is generated by the electrons excited in the conduction band moving by the applied electric field.
かかる電流が、超伝導量子干渉素子（SQUID）のリン
グ近傍に設けた配線を流れることによって磁場が発生
し、この磁場をSQUIDで検出するものである。Such a current flows through the wiring provided near the ring of the superconducting quantum interference device (SQUID) to generate a magnetic field, and this magnetic field is detected by the SQUID.
すなわち、入射光をSQUIDで検出できることになる。 That is, the incident light can be detected by the SQUID.
［実施例］ 以下、実施例により本発明を詳述する。EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples.
実施例１ 第１図に本発明に基づく一実施例の概念図を示す。図
中１は受光部、２は電流駆動用電源、３は磁場発生用配
線、４は超伝導リング、５は弱結合部、６はDC SQUID用
検出及びフィードバック回路部である。Embodiment 1 FIG. 1 shows a conceptual diagram of an embodiment based on the present invention. In the figure, 1 is a light receiving section, 2 is a current driving power supply, 3 is a magnetic field generating wiring, 4 is a superconducting ring, 5 is a weak coupling section, and 6 is a DC SQUID detection and feedback circuit section.
先ず、酸化物超伝導体YBa2Cu3O７−δ（Ｏ≦δ≦0.
5）をマグネトロンスパッタ法等によりMgO基板上に形成
し、フォトリソグラフィー技術等により得られた薄膜を
加工する。本実施例では、酸化物超伝導体を厚さ5000
Å、リング部の線幅50μｍ、弱結合部の線幅４μｍと
し、図の様な弱結合部52ケ所を有する超伝導リング４を
形成した。さらに、検出回路６に信号を送る為の電極７
をCr,Auで形成し、リングの上部にはMgOを3000Å成膜
し、さらにその上に磁場発生用配線３をAlで図のように
形成した。また、受光部１としてフォトダイオードを用
い、この部分はヒーターにより250Kにした。First, the oxide superconductor YBa 2 Cu 3 O 7-δ (O ≦ δ ≦ 0.
5) is formed on an MgO substrate by a magnetron sputtering method or the like, and a thin film obtained by a photolithography technique or the like is processed. In the present embodiment, the oxide superconductor has a thickness of 5000
(4) The line width of the ring portion was 50 μm and the line width of the weak coupling portion was 4 μm, and a superconducting ring 4 having 52 weak coupling portions as shown in the figure was formed. Further, an electrode 7 for sending a signal to the detection circuit 6
Was formed of Cr and Au, and MgO was formed on the upper part of the ring at a thickness of 3000 Å, and the magnetic field generating wiring 3 was formed thereon of Al as shown in the figure. Further, a photodiode was used as the light receiving section 1, and this section was heated to 250K by a heater.
かかる構成からなる素子を15Kの温度中に置き、雑音
を少なくした環境で測定を行った。先ず、電源２に10V
を印加した状態で、受光部に光を入射しない場合には、
SQUIDの検出部の電圧は、一定のままだった。次に受光
部に1mルクスの光を照射したところ、検出部に電圧の変
化が起った。このことは、SQUID内に磁場が発生したこ
とを意味している。The device having such a configuration was placed in a temperature of 15 K, and the measurement was performed in an environment where noise was reduced. First, 10V to power supply 2
When light is not incident on the light receiving unit with
The voltage at the detector of the SQUID remained constant. Next, when the light receiving section was irradiated with light of 1 mlux, a voltage change occurred in the detecting section. This means that a magnetic field was generated in the SQUID.
実施例２ 第２図に、磁場発生用コイル自身を受光部分にした第
２の実施例を示す。図中８は光導電体であり、４の超伝
導体とはMgO薄膜で絶縁してある。この素子を20Kの温度
にし、先ず、光照射しない暗状態で電源２に40Vかけた
ところ、暗電流が流れSQUIDに検出されたが一定値にお
ちついた。次に、光導電体８に10mルクスの光を照射し
たところ、光に応答してSQUIDにシグナルが検出され
た。これは光照射時に暗電流より大きい明電流が流れ、
それが磁場に変換されたことを意味する。Embodiment 2 FIG. 2 shows a second embodiment in which the magnetic field generating coil itself is used as a light receiving portion. In the figure, reference numeral 8 denotes a photoconductor, which is insulated from the superconductor 4 by an MgO thin film. When the temperature of this device was set to 20K and 40 V was applied to the power supply 2 in a dark state without light irradiation, a dark current flowed, but was detected by SQUID, but fell to a constant value. Next, when the photoconductor 8 was irradiated with light of 10 mlux, a signal was detected in the SQUID in response to the light. This means that a bright current larger than the dark current flows during light irradiation,
It means that it was converted to a magnetic field.
実施例３ 第３図に本発明の光検出素子を用いた分光器の実施例
を示す。図中9,14はスリット、10は入射光、11はフィル
ター、12は回折格子、13は光検出素子である。Embodiment 3 FIG. 3 shows an embodiment of a spectroscope using the photodetector of the present invention. In the figures, 9 and 14 are slits, 10 is incident light, 11 is a filter, 12 is a diffraction grating, and 13 is a photodetector.
上記分光器において、入射光10はスリット９によって
絞られ、さらにフィルター11を通過することによって特
定の波長域の光になる。そして、回折格子12に入射した
光は、波長ごとに異なる角度に回折される。よって、回
折格子表面と光軸のなす角度θを変えることにより、ス
リット14を通過する光の波長が変えられる。このように
分光された光は、本発明の光検出素子13に入射され検出
される。特に微弱な光の検出が必要となる分光器の場合
では、特に本発明の光検出素子が有効である。In the spectroscope, the incident light 10 is narrowed by the slit 9 and further passes through the filter 11 to become light in a specific wavelength range. Then, the light incident on the diffraction grating 12 is diffracted at different angles for each wavelength. Thus, by changing the angle θ between the diffraction grating surface and the optical axis, the wavelength of light passing through the slit 14 can be changed. The light thus split is incident on the photodetector 13 of the present invention and detected. In particular, in the case of a spectroscope that requires detection of weak light, the photodetector of the present invention is particularly effective.
［発明の効果］ 以上述べたように、本発明の光検出素子によれば、受
光部で発生した電流で生ずる磁場を超伝導体により検出
することができる。[Effects of the Invention] As described above, according to the photodetector of the present invention, the magnetic field generated by the current generated in the light receiving unit can be detected by the superconductor.
すなわち、本発明の光検出素子によれば、 （１）．従来（例えばジョセフソン接合の接合部に光を
照射するといった場合）に比べ、光信号と検出部の位置
合せが容易、すなわち、必要とする任意の大きさの受光
部（受信部）に光信号を入力することが可能となる。That is, according to the photodetector of the present invention, (1). Compared with the conventional case (for example, when light is radiated to the junction of a Josephson junction), the alignment of the optical signal and the detection unit is easy, that is, the optical signal is transmitted to the light receiving unit (reception unit) of any required size. Can be input.
（２）．光信号入力部（受光部）の材料を適宜選択する
ことにより、従来に比べ幅広い波長の信号検出が可能と
なる。(2). By appropriately selecting the material of the optical signal input section (light receiving section), it is possible to detect a signal of a wider wavelength than in the related art.
（３）.SQUIDを検出部に用いている為、従来の方式に比
べ高感度になる。(3) Since the SQUID is used for the detection unit, the sensitivity is higher than that of the conventional method.
（４）．超伝導リング内に出入りする磁場を対象にして
いるので、光強度も分かり易くなる。(4). Since the target is a magnetic field entering and exiting the superconducting ring, the light intensity can be easily understood.
といったような効果がある。There are such effects.
第１図は、受光部にフォトダイオード、検出部にDC SQU
IDを用いた本発明に係る光検出素子の概略図である。第
２図は、受光部に光導電性材料を用い、検出部にDC SQU
IDを用いた光検出素子の概略図である。第３図は、本発
明に係る光検出素子を用いた分光器を示す概略図であ
る。第４図は、従来の光信号検出素子の概略構成斜視図
である。 １……受光部、２……電流駆動用電源 ３……磁場発生用配線、４……超伝導リング ５……弱結合部 ６……DC SQUID用検出回路部 ７……電極、８……光導電体 9,14……スリット、10……入射光 11……フィルター、12……回折格子 13……光検出素子Fig. 1 shows a photodiode for the light receiving section and a DC SQU for the detecting section.
FIG. 3 is a schematic view of a photodetector according to the present invention using an ID. Fig. 2 shows a photo detector made of a photoconductive material and a DC SQU detector.
FIG. 3 is a schematic diagram of a photodetector using an ID. FIG. 3 is a schematic diagram showing a spectroscope using the photodetector according to the present invention. FIG. 4 is a schematic configuration perspective view of a conventional optical signal detection element. DESCRIPTION OF SYMBOLS 1 ... Light-receiving part, 2 ... Power supply for current drive 3 ... Wiring for magnetic field generation, 4 ... Superconducting ring 5 ... Weak coupling part 6 ... Detection circuit part for DC SQUID 7 ... Electrode, 8 ... Photoconductor 9, 14 Slit, 10 Incident light 11 Filter, 12 Diffraction grating 13 Photodetector
───────────────────────────────────────────────────── フロントページの続き (72)発明者 川崎 岳彦 東京都大田区下丸子３丁目30番２号 キ ヤノン株式会社内 (72)発明者 金子 典夫 東京都大田区下丸子３丁目30番２号 キ ヤノン株式会社内 (56)参考文献 特開 平１−110279（ＪＰ，Ａ) 特開 昭64−86575（ＪＰ，Ａ) ──────────────────────────────────────────────────続 き Continued on front page (72) Inventor Takehiko Kawasaki 3- 30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Norio Kaneko 3- 30-2 Shimomaruko, Ota-ku, Tokyo Canon (56) References JP-A-1-110279 (JP, A) JP-A-64-86575 (JP, A)
Claims (2)
流により磁場を発生させる配線と、かかる配線から生じ
た磁場を検出する超伝導量子干渉計を有する検出部とを
少なくとも有することを特徴とする光検出素子。1. A semiconductor device comprising: at least a light-receiving section for generating a current by light incidence, wiring for generating a magnetic field by the current, and a detecting section having a superconducting quantum interferometer for detecting a magnetic field generated from the wiring. Photodetector.
用いたことを特徴とする請求項１記載の光検出素子。2. The photodetector according to claim 1, wherein a photoconductive material is used as said magnetic field generating wiring.
Priority Applications (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1192528A JP2715320B2 (en) | 1989-07-27 | 1989-07-27 | Photodetector |
| EP93203066A EP0590738B1 (en) | 1989-07-05 | 1990-07-04 | Light detecting device and light detecting method using a superconductor |
| EP90307302A EP0407166B1 (en) | 1989-07-05 | 1990-07-04 | Light detecting device and light detection method |
| DE69031501T DE69031501T2 (en) | 1989-07-05 | 1990-07-04 | Device and method for measuring light using a superconductor |
| DE69009109T DE69009109T2 (en) | 1989-07-05 | 1990-07-04 | Device and method for measuring light. |
| US07/548,212 US5155093A (en) | 1989-07-05 | 1990-07-05 | Light detecting device and light detecting method using a superconnector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1192528A JP2715320B2 (en) | 1989-07-27 | 1989-07-27 | Photodetector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0357925A JPH0357925A (en) | 1991-03-13 |
| JP2715320B2 true JP2715320B2 (en) | 1998-02-18 |
Family
ID=16292782
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1192528A Expired - Fee Related JP2715320B2 (en) | 1989-07-05 | 1989-07-27 | Photodetector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2715320B2 (en) |
-
1989
- 1989-07-27 JP JP1192528A patent/JP2715320B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0357925A (en) | 1991-03-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP0590738B1 (en) | Light detecting device and light detecting method using a superconductor | |
| Richards | Bolometers for infrared and millimeter waves | |
| EP0354369B1 (en) | Infrared detector | |
| CN101038211B (en) | Detection device and image forming device | |
| EP0534768A1 (en) | Uncooled infrared detector and method for forming the same | |
| US5331162A (en) | Sensitive, low-noise superconducting infrared photodetector | |
| JP2715320B2 (en) | Photodetector | |
| CN113049096A (en) | Nickel telluride terahertz detector integrated with room-temperature periodic logarithmic antenna and preparation method | |
| Semkin et al. | Gate-controlled polarization-resolving mid-infrared detection at metal–graphene junctions | |
| JPH05264343A (en) | Far-infrared spectral light detector | |
| US6787757B2 (en) | Apparatus and methods for generating an electronic signal responsive to selected light | |
| Khrebtov | Noise properties of high temperature superconducting bolometers | |
| US6316771B1 (en) | Superlattice tunable detector system | |
| Comstock et al. | Magneto‐Optic Properties of CrTe Films Prepared by Sequential Evaporation | |
| JP2737006B2 (en) | Signal detector | |
| Chopra et al. | Thin film thermal device applications | |
| JP2715321B2 (en) | Photo detector | |
| JP2737003B2 (en) | Signal detection method | |
| JP2737007B2 (en) | Signal detector | |
| NL8820965A (en) | METHOD FOR MEASURING SPATIAL DISTRIBUTION OF ELECTROMAGNETIC RADIATION INTENSITY. | |
| JP2737004B2 (en) | Signal detection method | |
| Semkin et al. | Polarization-resolving graphene-based mid-infrared detector | |
| CN114414214B (en) | Optical detector for directly detecting optical orbital angular momentum and detection method thereof | |
| Elliott | An infrared detector with integrated signal processing | |
| SU1032959A1 (en) | Superconducting photocell |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20081107 Year of fee payment: 11 |
|
| LAPS | Cancellation because of no payment of annual fees |