CN102522470A - Electric control structure and electric control method for implementation of surface plasmon polariton photon modulation - Google Patents
Electric control structure and electric control method for implementation of surface plasmon polariton photon modulation Download PDFInfo
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- CN102522470A CN102522470A CN2011104309877A CN201110430987A CN102522470A CN 102522470 A CN102522470 A CN 102522470A CN 2011104309877 A CN2011104309877 A CN 2011104309877A CN 201110430987 A CN201110430987 A CN 201110430987A CN 102522470 A CN102522470 A CN 102522470A
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Abstract
The invention provides an electric control structure and an electric control method for implementation of surface plasmon polariton photon modulation. The method for implementation of surface plasmon polariton photon modulation includes: making a semiconductor heterojunction and forming two-dimensional electron gas under the surface of the semiconductor heterojunction; preparing a metal nano wire on the surface of the semiconductor heterojunction to use the metal nano wire as a surface plasmon polariton waveguide; making a metal electrode close to the metal nano wire for controlling quantum dot properties, wherein the metal electrode forms quantum dot luminophor in the two-dimensional electron gas after being powered; and adjusting voltage of the metal electrode to control the control quantum dot properties.
Description
Technical field
The present invention relates to the cross-application field of surface phasmon photonic propulsion and quantum information technology, more particularly, the present invention relates to a kind of electricity control method of realizing the surface phasmon photonic modulation.
Background technology
Surface phasmon is that conductive surface comes from the charge density wave of free electron collective oscillation and a kind of propagation exciton that its electromagnet mode is united formation.
The same with traditional medium optical fiber, the wide range continuous mode of surface phasmon is restricted to plain conductor, and propagates along the direction of principal axis of lead.But different with traditional medium optical fiber is that the scale size and the diameter of wire of the surface phasmon pattern of local in conductive wire cross-section are suitable.This means that surface phasmon can break through the restriction of diffraction limit, can below 100 nanometers, realize the local and the control of light field.
Just because of the above-mentioned this sub-wavelength local characteristic of surface phasmon, therefore the phasmon photonic propulsion also becomes a very active emerging optical branching of Recent study.In numerous cutting edge technologies fields such as it is made at bio-sensing, wave spectrum detection, micro-imaging, light source, sub-wavelength optics and nano photoelectric are integrated charming application prospect is arranged.
The quantum information technology is the emerging cutting edge technology that research information is handled, and purpose is improving arithmetic speed, guarantee information security, increase information capacity and improving the limit that aspects such as accuracy of detection break through existing classical information system.Quantum communications of quantum information technology and quantum computer, wherein the difficulty succeeded in developing of quantum computer is very big, and remarkable break-throughs are not arranged at present as yet, and topmost bottleneck problem is the integrated and chipization of quantum calculation.
The single photon modulator is a vitals in the quantum calculation system, mainly is used for controlling the transport property of coherent photons.Single photon modulator that can be integrated need be realized strong relevant coupling between single luminous element and the photon.For the luminous element of nanoscale,,, cause The interaction distance between the two very short because its yardstick and optical wavelength differ two one magnitude like quantum dot.But prior art can not be carried out the modulation of single photon on the sheet well.
Summary of the invention
Technical problem to be solved by this invention is to having above-mentioned defective in the prior art, and a kind of electricity control structure and method of realization surface phasmon photonic modulation of the modulation that can carry out single photon on the sheet is provided.
According to a first aspect of the invention, a kind of electricity control structure of realizing the surface phasmon photonic modulation is provided, has comprised: surface phasmon waveguide, semiconductor-quantum-point luminous element, a plurality of the 3rd metal electrode; Wherein, said a plurality of metal electrode is arranged in the same side of surface phasmon waveguide; And the semiconductor-quantum-point luminous element is formed in the middle of said a plurality of the 3rd metal electrode.
Preferably, said a plurality of metal electrode comprises two first metal electrodes, two second metal electrodes and the 3rd metal electrode; Wherein, two first metal electrode shapes are identical, and two second metal electrode shapes are identical; And two first metal electrodes are arranged symmetrically in the 3rd metal electrode both sides, and two second metal electrodes are arranged symmetrically in the 3rd metal electrode both sides.
Preferably, be provided with the thick dielectric layer of 1-100nm between surface phasmon waveguide and the semiconductor-quantum-point luminous element.
Preferably, the surface phasmon waveguide is the nano wire of gold, silver, copper, aluminium material.
According to a second aspect of the invention; The method of a kind of manufacturing according to the electricity control structure of the described realization surface phasmon of first aspect present invention photonic modulation is provided; Comprise: make a heterojunction semiconductor, under said heterojunction semiconductor surface, form two-dimensional electron gas; At said heterojunction semiconductor surface preparation metal nanometer line, as the surface phasmon waveguide; Near said metal nanometer line, make the metal electrode that is used to control quantum dot character, said metal electrode energising back has formed the quantum dot light emitting body in the semiconductor two-dimensional electron gas.
According to a second aspect of the invention, a kind of electricity control method of realizing the surface phasmon photonic modulation is provided, has comprised: made a heterojunction semiconductor, under said heterojunction semiconductor surface, form two-dimensional electron gas; At said heterojunction semiconductor surface preparation metal nanometer line, as the surface phasmon waveguide; Near said metal nanometer line, make the metal electrode that is used to control quantum dot character, said metal electrode energising back has formed the quantum dot light emitting body in the semiconductor two-dimensional electron gas; And the voltage on the adjustment metal electrode is with control quantum dot character.
Preferably, said quantum dot character comprises quantum dot shape and inner level spacing size.
Preferably, said metal electrode comprises two first metal electrodes, two second metal electrodes and the 3rd metal electrode,, two first metal electrodes, two second metal electrodes and the 3rd metal electrode are arranged in the same side of surface phasmon waveguide; And the semiconductor-quantum-point luminous element is formed in the middle of two first metal electrodes, two second metal electrodes and the 3rd metal electrode.
Preferably, two first metal electrode shapes are identical, and two second metal electrode shapes are identical; And two first metal electrodes are arranged symmetrically in the 3rd metal electrode both sides, and two second metal electrodes are arranged symmetrically in the 3rd metal electrode both sides.
Preferably, the surface phasmon waveguide is the nano wire of gold, silver, copper, aluminium material.
According to the present invention; Utilize the sub-wavelength local characteristic of surface phasmon to realize being coupled strong being concerned with of photon in single semiconductor light emitting body and the surface phasmon waveguide; Through the character of electricity means control semiconductor light emitting body, thereby the surface phasmon single photon is modulated.
More particularly, in the present invention, luminous element is the quantum dot that is formed by heterojunction semiconductor, and near the metal nanometer line it is the carrier of photon as the surface phasmon waveguide.Because relevant by force coupling can take place in the sub-wavelength local characteristic of surface phasmon between the photon in quantum dot light emitting body and the metal nanometer line.Adjustment is added in voltage swing on the metal electrode and controls electron amount and level spacing in the quantum dot, suppose that the adjustment electrode voltage makes two energy levels of existence in the quantum dot, and promptly quantum dot is made up of a ground state and an excitation state.Surface phasmon photon transmission character is decided by quantum dot two energy level difference Δs and propagates the relation between photon frequency w.When surface phasmon photon and quanta point resonance (during Δ=w), because the photon of strong relevant coupling frequency w will be reflected back.Therefore, quantum dot just is equivalent to mirror for the surface phasmon photon, and control quantum dot energy level extent just can determine whether the surface phasmon photon reflects or transmission, therefore reaches the single photon modulating action.
The present invention utilizes the carrier of surface phasmon as photon, adopts dull and stereotyped semiconductor technology to make quantum dot and metal waveguide, has realized the relevant modulation to single photon.Fast based on the single photon modulator responses time of the present invention, modulation depth is big, have again to be easy to control device pattern, compact conformation, to be prone to and the integrated characteristics of external circuit.
Description of drawings
In conjunction with accompanying drawing, and, will more easily more complete understanding be arranged and more easily understand its attendant advantages and characteristic the present invention through with reference to following detailed, wherein:
Fig. 1 is the electricity control structure sketch map of surface phasmon photonic modulation in the embodiment of the invention.
Need to prove that accompanying drawing is used to explain the present invention, and unrestricted the present invention.Notice that the accompanying drawing of expression structure possibly not be to draw in proportion.And in the accompanying drawing, identical or similar elements indicates identical or similar label.
Embodiment
In order to make content of the present invention clear more and understandable, content of the present invention is described in detail below in conjunction with specific embodiment and accompanying drawing.
See also Fig. 1, Fig. 1 is an electricity control structure sketch map of realizing the surface phasmon photonic modulation in the embodiment of the invention; As shown in the figure, comprise according to the electricity control structure of the realization surface phasmon photonic modulation of the embodiment of the invention: surface phasmon waveguide 1, semiconductor-quantum-point luminous element 2, a plurality of metal electrode.
In the example depicted in fig. 1, showing a plurality of metal electrodes is: two first metal electrodes 3, two second metal electrodes 4 and the 3rd metal electrodes 5.
Wherein, two first metal electrodes 3, two second metal electrodes 4 and the 3rd metal electrode 5 are arranged in the same side of surface phasmon waveguide 1.Semiconductor-quantum-point luminous element 2 is formed in the middle of two first metal electrodes 3, two second metal electrodes 4 and the 3rd metal electrode 5.
Wherein, two first metal electrode 3 shapes are identical, and also shape is identical for two second metal electrodes 4.And two first metal electrodes 3 are arranged symmetrically in the 3rd metal electrode 5 both sides, and two second metal electrodes 4 are arranged symmetrically in the 3rd metal electrode 5 both sides.
Need to prove that the number and the layout of metal electrode are not limited to this, but can be the metal electrode of other quantity and/or other arrangement that for example the number of metal electrode becomes 3,4,6,7 etc.Fig. 1 only shows the preferred implementation of metal electrode.Specifically; Preferably; The number of metal electrode is odd number 2N+1, wherein has N that same metal electrode is centered on another metal electrode symmetric arrangement (that kind as shown in Figure 1), like this; N can be conditioned voltage on the same metal electrode so that energy level is made up of a ground state and an excitation state in the quantum dot, and the voltage on that single metal electrode can be used to control energy level extent in the semiconductor-quantum-point luminous element 2.Thus, can on the basis of described 5 metal electrodes of Fig. 1, increase the metal electrode of even number symmetry, perhaps deduct from the basis of described 5 metal electrodes of Fig. 1 pair of metal electrodes (for example, first metal electrode to or second metal electrode to).
In the electricity control structure in Fig. 1, metal nanometer line is formed surface phasmon waveguide 1, is semiconductor-quantum-point luminous element 2 near the surface phasmon waveguide 1.The curve that has arrow among Fig. 1 is represented the surface phasmon photon of propagating in the waveguide, and arrow is represented the direction of propagation.
Alternatively, visual concrete condition is provided with the thick dielectric layer (not shown) of 1-100nm between surface phasmon waveguide 1 and the semiconductor-quantum-point luminous element 1.
Manufacturing process according to the electricity control structure of the realization surface phasmon photonic modulation of the embodiment of the invention is described below.
The present invention can adopt dull and stereotyped semiconductor technology, such as GaAs/AlGaAs, is at first forming two-dimensional electron gas from for example about 1-100nm place, this heterojunction semiconductor surface.
Subsequently, at heterojunction semiconductor surface preparation metal nanometer line, as the surface phasmon waveguide.Specifically, the electron mobility of this two-dimensional electron gas is approximately 5 * 105cm2V
-1s
-1, electron density is 1 * 1011cm
-2Prepare nano wire at semiconductor surface with materials such as gold, silver, copper, aluminium, as surface phasmon waveguide 1.
After this, near nano wire, make the metal electrode that is used to control character such as quantum dot shape and inner level spacing size, these metal electrode energising backs have just formed the quantum dot light emitting body in the semiconductor two-dimensional electron gas.Specifically, near nano wire, make two first metal electrodes 3, two second metal electrodes 4 and the 3rd metal electrodes 5, the energising back forms semiconductor-quantum-point luminous element 2.Fig. 1 shows near the situation of the surface phasmon waveguide, making one semiconductor-quantum-point luminous element 1, still, in fact, also can make a plurality of semiconductor-quantum-point luminous elements 1 that keep at a certain distance away.
Further describe electricity control method below according to the realization surface phasmon photonic modulation of the embodiment of the invention.
In the electricity control method of realizing the surface phasmon photonic modulation; The voltage that can adjust on the metal electrode can be controlled quantum dot character; Especially energy level extent; And then the surface phasmon photon of the relevant coupling still transmission that whether is reflected by force of decision and quantum dot light emitting body, realize the single photon modulation.
Specifically, adjust the voltage on first metal electrode 3 and second metal electrode 4, so that energy level is made up of a ground state and an excitation state in the quantum dot.Photon in the surface phasmon waveguide 1 can excite generation for one section at metal nanometer line by laser focusing, also can excite through additive method.
The voltage of adjusting on the 3rd metal electrode 5 can be controlled energy level extent in the semiconductor-quantum-point luminous element 2, and then whether decision surface phasmon photon is reflected or transmission the modulation of realization single photon.
For raising the efficiency, the distance that adjustment surface phasmon waveguide 1 and semiconductor-quantum-point luminous element are 2 makes the near field stiffness of coupling of 2 of surface phasmon waveguide 1 and semiconductor-quantum-point luminous elements reach the strongest.
In the above-described embodiments, luminous element is the quantum dot that is formed by heterojunction semiconductor, and near the metal nanometer line it is the carrier of photon as the surface phasmon waveguide.Because relevant by force coupling can take place in the sub-wavelength local characteristic of surface phasmon between the photon in quantum dot light emitting body and the metal nanometer line.Adjustment is added in voltage swing on the metal electrode and controls electron amount and level spacing in the quantum dot, suppose that the adjustment electrode voltage makes two energy levels of existence in the quantum dot, and promptly quantum dot is made up of a ground state and an excitation state.Surface phasmon photon transmission character is decided by quantum dot two energy level difference Δs and propagates the relation between photon frequency w.When surface phasmon photon and quanta point resonance (during Δ=w), because the photon of strong relevant coupling frequency w will be reflected back.Therefore, quantum dot just is equivalent to mirror for the surface phasmon photon, and control quantum dot energy level extent just can determine whether the surface phasmon photon reflects or transmission, therefore reaches the single photon modulating action.
The single photon modulator responses time that the above embodiment of the present invention realizes is fast, modulation depth is big, has again to be easy to control device pattern, compact conformation, the easy and integrated characteristics of external circuit, can be applicable to fields such as quantum calculation.
It is understandable that though the present invention with the preferred embodiment disclosure as above, yet the foregoing description is not in order to limit the present invention.For any those of ordinary skill in the art; Do not breaking away under the technical scheme scope situation of the present invention; All the technology contents of above-mentioned announcement capable of using is made many possible changes and modification to technical scheme of the present invention, or is revised as the equivalent embodiment of equivalent variations.Therefore, every content that does not break away from technical scheme of the present invention, all still belongs in the scope of technical scheme protection of the present invention any simple modification, equivalent variations and modification that above embodiment did according to technical spirit of the present invention.
Claims (10)
1. an electricity control structure of realizing the surface phasmon photonic modulation is characterized in that comprising: surface phasmon waveguide, semiconductor-quantum-point luminous element, a plurality of the 3rd metal electrode; Wherein, said a plurality of metal electrode is arranged in the same side of surface phasmon waveguide; And the semiconductor-quantum-point luminous element is formed in the middle of said a plurality of the 3rd metal electrode.
2. the electricity control structure of realization surface phasmon photonic modulation according to claim 1 is characterized in that, said a plurality of metal electrodes comprise two first metal electrodes, two second metal electrodes and the 3rd metal electrode; Wherein, two first metal electrode shapes are identical, and two second metal electrode shapes are identical; And two first metal electrodes are arranged symmetrically in the 3rd metal electrode both sides, and two second metal electrodes are arranged symmetrically in the 3rd metal electrode both sides.
3. the electricity control structure of realization surface phasmon photonic modulation according to claim 1 and 2 is characterized in that, is provided with the thick dielectric layer of 1-100nm between surface phasmon waveguide and the semiconductor-quantum-point luminous element.
4. the electricity control structure of realization surface phasmon photonic modulation according to claim 1 and 2 is characterized in that, the surface phasmon waveguide is the nano wire of gold, silver, copper, aluminium material.
5. a manufacturing is characterized in that comprising according to the method for the electricity control structure of the described realization surface phasmon of one of claim 1 to 4 photonic modulation:
Make a heterojunction semiconductor, under said heterojunction semiconductor surface, form two-dimensional electron gas;
At said heterojunction semiconductor surface preparation metal nanometer line, as the surface phasmon waveguide;
Near said metal nanometer line, make the metal electrode that is used to control quantum dot character, said metal electrode energising back has formed the quantum dot light emitting body in the semiconductor two-dimensional electron gas.
6. electricity control method of realizing the surface phasmon photonic modulation is characterized in that comprising:
Make a heterojunction semiconductor, under said heterojunction semiconductor surface, form two-dimensional electron gas;
At said heterojunction semiconductor surface preparation metal nanometer line, as the surface phasmon waveguide;
Near said metal nanometer line, make the metal electrode that is used to control quantum dot character, said metal electrode energising back has formed the quantum dot light emitting body in the semiconductor two-dimensional electron gas; And
Voltage on the adjustment metal electrode is with control quantum dot character.
7. the electricity control method of realization surface phasmon photonic modulation according to claim 6 is characterized in that, said quantum dot character comprises quantum dot shape and inner level spacing size.
8. according to the electricity control method of claim 6 or 7 described realization surface phasmon photonic modulation; It is characterized in that; Said metal electrode comprises two first metal electrodes, two second metal electrodes and the 3rd metal electrode;, two first metal electrodes, two second metal electrodes and the 3rd metal electrode are arranged in the same side of surface phasmon waveguide; And the semiconductor-quantum-point luminous element is formed in the middle of two first metal electrodes, two second metal electrodes and the 3rd metal electrode.
9. the electricity control method of realization surface phasmon photonic modulation according to claim 8 is characterized in that, two first metal electrode shapes are identical, and two second metal electrode shapes are identical; And two first metal electrodes are arranged symmetrically in the 3rd metal electrode both sides, and two second metal electrodes are arranged symmetrically in the 3rd metal electrode both sides.
10. according to the electricity control method of claim 6 or 7 described realization surface phasmon photonic modulation, it is characterized in that the surface phasmon waveguide is the nano wire of gold, silver, copper, aluminium material.
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Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
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CN105576054A (en) * | 2016-03-23 | 2016-05-11 | 南京大学 | Nanowire intermediate band solar cell structure based on butterfly-shaped plasmon antenna enhancement |
CN109004508A (en) * | 2018-07-03 | 2018-12-14 | 北京邮电大学 | A kind of single-photon source based on quantum dot |
WO2019169747A1 (en) * | 2018-03-07 | 2019-09-12 | 东南大学 | Surface plasmon-optic-electric hybrid conducting nanoheterostructure and preparation method therefor |
WO2021253829A1 (en) * | 2020-06-17 | 2021-12-23 | 武汉大学 | Light source with both high quantum yield and high bandwidth |
Citations (1)
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CN102176463A (en) * | 2010-12-21 | 2011-09-07 | 上海电机学院 | Terahertz photon on chip control system and control method thereof |
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CN102176463A (en) * | 2010-12-21 | 2011-09-07 | 上海电机学院 | Terahertz photon on chip control system and control method thereof |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105576054A (en) * | 2016-03-23 | 2016-05-11 | 南京大学 | Nanowire intermediate band solar cell structure based on butterfly-shaped plasmon antenna enhancement |
WO2019169747A1 (en) * | 2018-03-07 | 2019-09-12 | 东南大学 | Surface plasmon-optic-electric hybrid conducting nanoheterostructure and preparation method therefor |
US11099323B2 (en) | 2018-03-07 | 2021-08-24 | Southeast University | Surface plasmon-optical-electrical hybrid conduction nano heterostructure and preparation method therefor |
CN109004508A (en) * | 2018-07-03 | 2018-12-14 | 北京邮电大学 | A kind of single-photon source based on quantum dot |
WO2021253829A1 (en) * | 2020-06-17 | 2021-12-23 | 武汉大学 | Light source with both high quantum yield and high bandwidth |
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Application publication date: 20120627 |