WO2017193520A1 - 电子群态纠缠浓缩方法和装置 - Google Patents

电子群态纠缠浓缩方法和装置 Download PDF

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WO2017193520A1
WO2017193520A1 PCT/CN2016/099535 CN2016099535W WO2017193520A1 WO 2017193520 A1 WO2017193520 A1 WO 2017193520A1 CN 2016099535 W CN2016099535 W CN 2016099535W WO 2017193520 A1 WO2017193520 A1 WO 2017193520A1
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state
spin
initial
entangled
entanglement
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PCT/CN2016/099535
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French (fr)
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刘炯
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中兴通讯股份有限公司
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/70—Photonic quantum communication

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  • the present invention relates to the field of communications technologies, and in particular, to an electronic group entanglement concentration method and apparatus.
  • the largest entangled group plays a very important role in both quantum communication and quantum computing.
  • the maximum entangled group state prepared in advance will inevitably interact with the surrounding environment to produce decoherence, from the maximum entangled group state to the mixed state or the non-maximally entangled pure state.
  • Entanglement purification is to extract the desired maximum entangled state from the mixed state.
  • Entanglement concentrating is to obtain the maximum entangled state from the non-maximally entangled pure state.
  • the object of the present invention is to solve at least one of the above technical problems to some extent.
  • the first object of the present invention is to provide an electronic group entanglement concentration method which improves the success probability of entanglement concentration of electronic group states.
  • a second object of the present invention is to provide an electronic group entanglement concentrating device.
  • an electronic group entanglement and concentration method includes the following steps: acquiring a first initial entangled group state to be entangled and concentrated, and generating information according to the information of the first initial entangled group state An auxiliary electronic state; the first auxiliary electronic state and the first initial correction according to the first polarization beam splitter
  • the first electron in the group is subjected to non-destructive measurement; the result of the non-destructive measurement is judged by the charge detector as an odd parity; if the result of the non-destructive measurement is an odd parity, then the preset spatial mode is The electrons are processed to obtain the maximum entangled group state; if the result of the non-destructive measurement is the even parity, the two electrons in the same spatial mode are divided into two spatial modes by the second polarization beam splitter, The electrons in the preset spatial mode are processed to obtain the second initial entangled group state for the next round of entanglement and concentration processing.
  • the first initial entangled group state to be entangled and concentrated is obtained, and the first auxiliary electronic state is generated according to the information of the first initial entangled group state, and then the first polarization splitting is performed according to the first polarization grouping
  • the device performs non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state, and determines whether the result of the non-destructive measurement is an odd parity by the charge detector, if the result of the non-destructive measurement is Qi Yu said that the electrons in the preset spatial mode are processed to obtain the maximum entangled group state.
  • the two in the same spatial mode are made by the second polarization beam splitter.
  • the electrons are divided into two spatial modes, and the electrons in the pre-set spatial mode are processed to obtain the second initial entangled group state for the next round of entanglement and concentration processing.
  • the method improves the success probability of entanglement concentration and the utilization of entangled resources, and is suitable for entanglement and concentration of any K particle group state, and has high availability and adaptability.
  • the processing the electrons in the preset spatial mode to obtain the maximum entangled group state includes: performing a Hadamard transform operation on the electrons of the preset space mode; and detecting the electrons passing through the Hadamard transform operation Whether the spin state is a spin-up state, and the maximum entangled group state is obtained according to the detection result.
  • the obtaining the maximum entangled group state according to the detection result comprises: if the detection knows that the electron spin state is a spin-up state, acquiring a first maximum entangled group state; if detecting the known electronic spin state For the spin down state, a phase flip operation is performed to obtain the maximum entangled group state.
  • the processing the electrons in the preset spatial mode after the separation, acquiring the second initial entangled group state for the next round of entanglement and concentration processing comprising: performing Hadamard on the electrons of the preset preset spatial mode Transforming operation; detecting whether the electron spin state of the Hadamard transform operation is a spin-up state, acquiring a second initial entangled group state according to the detection result; generating a second auxiliary electronic state according to the information of the second initial entangled group state, so that Carry out the next round of entanglement and concentration treatment.
  • the acquiring the second initial entangled group state according to the detection result includes: acquiring a second initial entangled group state if the detected electronic spin state is a spin-up state; When the spin state is a spin down state, a phase flip operation is performed to obtain a second initial entangled group state.
  • an electronic group entanglement and concentration apparatus includes: a generating module, configured to acquire a first initial entangled group state to be entangled and concentrated, according to the first initial entangled group state The information generates a first auxiliary electronic state; and the measuring module is configured to perform non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state according to the first polarization beam splitter; a judging module, configured to determine, by the charge detector, whether the result of the non-destructive measurement is an odd parity; the first processing module is configured to perform the electronic of the preset spatial mode when the result of the non-destructive measurement is an odd parity Processing, obtaining a maximum entangled group state; a second processing module, when the result of the non-destructive measurement is even parity, the two electrons in the same spatial mode are divided into two by the second polarization beam splitter In the spatial mode, the electrons in
  • An electronic group entanglement concentrating device obtains a first initial entangled group state to be entangled and concentrated, generates a first auxiliary electronic state according to information of the first initial entangled group state, and further splits according to the first polarization
  • the device performs non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state, and determines whether the result of the non-destructive measurement is an odd parity by the charge detector, if the result of the non-destructive measurement is Qi Yu said that the electrons in the preset spatial mode are processed to obtain the maximum entangled group state.
  • the two in the same spatial mode are made by the second polarization beam splitter.
  • the electrons are divided into two spatial modes, and the electrons in the pre-set spatial mode are processed to obtain the second initial entangled group state for the next round of entanglement and concentration processing.
  • the device improves the success probability of entanglement concentration and the utilization of entangled resources, and is suitable for entanglement and concentration of any K particle group state, and has high availability and adaptability.
  • the first processing module includes: a first transforming unit, configured to perform a Hadamard transform operation on the electrons of the preset spatial mode; and a first acquiring unit, configured to detect the Hadamard transform operation. Whether the electron spin state is a spin-up state, and the maximum entangled group state is obtained according to the detection result.
  • the first acquiring unit is configured to: when detecting that the state of the electron spin is a spin-up state, acquiring a first maximum entangled group state; and detecting that the state of the electron spin is a spin direction In the down state, the phase flip operation is performed to obtain the maximum entangled group state.
  • the second processing module includes: a second transform unit configured to perform a Hadamard transform operation on the separated preset spatial mode; and a second obtaining unit configured to detect the Hadamard transform operation Whether the electron spin state is a spin-up state, and acquiring a second initial entangled group state according to the detection result; and generating means for generating a second auxiliary electronic state according to the information of the second initial entangled group state, so as to proceed to the next Wheel entanglement and concentration treatment.
  • the second acquiring unit is configured to: acquire a second initial entangled group state when detecting that the state of the electron spin is a spin-up state; and detect a known spin state of the electron as a spin direction In the lower state, a phase inversion operation is performed to obtain a second initial entangled group state.
  • FIG. 1 is a flow chart of an electronic group entanglement concentration method according to an embodiment of the present invention
  • FIG. 2 is a schematic diagram showing the principle of electronic group non-destructive measurement according to an embodiment of the present invention
  • FIG. 3 is a flow chart of an electronic group entanglement concentration method according to an embodiment of the present invention.
  • FIG. 4 is a schematic diagram of an electronic group entanglement concentration method according to an embodiment of the present invention.
  • 5 is a schematic diagram showing the relationship between the probability of success of cyclic concentration and the initial state coefficient ⁇ , the number of particles K, and the number n of cycles of concentration;
  • FIG. 6 is a schematic structural view of an electronic group entanglement concentrating device according to an embodiment of the present invention.
  • FIG. 7 is a schematic structural view of an electronic group entanglement concentrating device according to an embodiment of the present invention.
  • FIG. 8 is a schematic structural view of an electronic group entanglement concentrating device according to another embodiment of the present invention.
  • the electronic group entanglement concentration method includes:
  • the initial entangled group state is a non-maximally entangled group state.
  • an auxiliary electronic state of information generated depending on the initial entangled group state is also required, and in the initial stage of each round of entanglement concentration, preparation and The state of the secondary entangled group state corresponds to the auxiliary electronic state.
  • a first initial entangled group state to be entangled and concentrated may be obtained, and a first auxiliary electronic state is generated according to the information of the first initial entangled group state, so as to further perform entanglement and concentration processing on the first initial entangled group state.
  • the electronic group state is divided into an odd parity and an even parity to perform entanglement and concentration processing, respectively, thereby realizing the process of entanglement and concentration of the entire electronic group. Therefore, before concentrating the first initial entangled group state, it is necessary to distinguish the odd parity and the even parity.
  • the electrons are independent of each other in terms of electronic degrees of freedom and spin degrees of freedom, when the charge detector is used to detect the charge number of the electronic system, the spin freedom of the electronic system is not affected. . Similarly, operating the spin-degree of freedom of an electronic system does not affect its charge. Therefore, the first polarization beam splitter is non-destructive to the measurement process of the first electron.
  • the number of electrons detected by the charge detector is used to determine whether the entangled state is an odd parity.
  • FIG. 2 is as follows:
  • FIG. 2 is a schematic diagram showing the principle of electronic group non-destructive measurement according to an embodiment of the present invention.
  • the first auxiliary electronic state and the first initial entangled group state are obtained by the first polarization beam splitter PBS.
  • the first electrons a and b are non-destructively measured.
  • the input first electrons a and b may be spin up state
  • the spin-up electrons will be completely transmitted.
  • the spin-down electrons will be completely reflected as they pass through the polarizing beam splitter.
  • the output forms of a1, b1 after passing through the first polarization beam splitter are:
  • the first polarization beam splitter After passing through the first polarization beam splitter, they can be divided into two categories in spatial mode. One type is that there is one and only one electron in the spatial patterns a1, b1. The other is that there are two electrons in the spatial pattern a1(b1), and the spatial pattern b1(a1) has no electrons.
  • the initial electron spin state is
  • the number of charges measured by the charge detector P is 1.
  • the initial electron spin state is
  • the number of charges measured by the charge detector P is 2.
  • the initial electron spin state is
  • the number of charges measured by the charge detector P is zero.
  • the electrons in the preset spatial mode are processed to obtain a maximum entangled group state.
  • the maximum entangled state can be obtained by performing entanglement concentration processing on the entangled group state of the odd parity.
  • the Hadamard transform operation may be performed on the electrons of the preset spatial mode to detect whether the electron spin state after the Hadamard transform operation is a spin-up state, and is obtained according to the detection result. Maximum entangled group state.
  • the detection knows that the electron spin state is a spin-up state, the first maximum entangled group state is acquired. If the detection knows that the electron spin state is a spin-down state, a phase flip operation is performed to obtain a maximum entangled group state.
  • the two electrons in the same spatial mode are divided into two spatial modes by the second polarization beam splitter, and the preset spatial mode is separated.
  • the electrons are processed to obtain a second initial entangled group state for the next round of entanglement concentration processing.
  • step S140 one round of entanglement concentration processing has been successfully completed.
  • step S140 only the case of odd parity was selected, and the case of even parity was regarded as "failure". This is relatively low for the success probability of entanglement enrichment and the utilization of resources.
  • the entangled state of the even parity is used as the initial entangled group state resource of the next entanglement and concentration process, and the entangled state of the even parity is cyclically entangled and concentrated.
  • two electrons in the same spatial mode are required to be divided into two spatial modes by the second polarization beam splitter, and the preset spatial mode is separated.
  • the electrons are processed to obtain a second initial entangled group state for the next round of entanglement concentration processing.
  • the Hadamard transform operation is performed on the electrons in the preset spatial mode after the separation, and whether the electron spin state after the Hadamard transform operation is detected is a spin-up state, and the second initial entangled group state is obtained according to the detection result, that is, if the detection is known When the electron spin state is a spin-up state, a second initial entangled group state is obtained. If the detection knows that the electron spin state is a spin-down state, a phase flip operation is performed to obtain a second initial entangled group state.
  • the obtained second initial entangled group state has exactly the same form as the first initial entangled group state. Therefore, the second initial entangled group state can be used as the initial entangled group state of the next round of entanglement concentration. Therefore, a higher probability of success of entanglement enrichment can be achieved by continuously repeating the entanglement concentration process.
  • the total success probability of the cycle n rounds is:
  • the electronic group state of the embodiment of the present invention will be described in detail by taking the first initial electronic group state as a four-particle group state as an example with reference to FIG. 3 and FIG. Entanglement and concentration method.
  • FIG. 3 is a flow chart of an electronic group entanglement concentration method
  • FIG. 4 is a schematic diagram of an electronic group entanglement concentration method, which is illustrated as follows:
  • the four-particle group state of the non-maximally entangled group state to be entangled and concentrated is obtained, that is, the entangled group states of four particles a, b, c and d are obtained, and the four-particle group state has the following general forms:
  • the coefficients ⁇ and ⁇ satisfy the normalization condition, that is, 2(
  • 2 ) 1.
  • the subscripts a, b, c, and d indicate that the particles of the group state are owned by different four parties.
  • the auxiliary electronic station depends on the four-particle group state, and the auxiliary electron is in the form of:
  • the charge detector determines whether the result of the non-destructive measurement is an odd parity.
  • the electrons d and e are non-destructively measured by the first polarization beam splitter PBS1, and the charges of the electrons (d1 and e1) processed by the PBS1 are detected by the charge detector P to determine whether it is Qi Yu said.
  • the electron spin state subjected to the Hadamard transform operation is a spin-up state
  • Dick uses a charge detector to detect electrons whose spatial pattern is f 3 .
  • the measurement result namely the spin up state or the spin down state.
  • the same maximum entangled state as when the measurement result is the spin-up state can be obtained.
  • the charge detector detects 0
  • the occasional parity case is selected, that is, in the case where the electrons in the spatial modes d and e are
  • a Hadamard operation is performed on the electrons of the spatial mode f4 and measured.
  • S3100 detects whether the spin state of the electron is a spin-up state.
  • S3110 Acquire a second initial entangled group state if the detection knows that the electron spin state is a spin-up state.
  • phase inversion operation is performed to obtain a second initial entangled group state.
  • S3130 Generate an auxiliary electronic state corresponding to the second initial entangled group state.
  • step S320 is performed to perform the next round of entanglement concentration processing.
  • the entangled state of the electron spin arbitrary K particle group state is as follows:
  • Dick has an electron with the subscript K. According to the same principle, Dick first needs to prepare an auxiliary electron in the form of:
  • FIG. 5 is a schematic diagram showing the relationship between the probability of success of cyclic concentration and the initial state coefficient ⁇ , the number of particles K, and the number n of cycles of concentration, as shown in FIG. 5, when the number of cycles of concentration is high, for any K particle group state The success rate of entanglement and concentration treatment is higher.
  • the implementation scheme of the electronic group entanglement and concentration described above can be applied not only to the entanglement and concentration of the four-particle group state, but also to the case of any K particle group state.
  • the electronic group entanglement concentration method of the embodiment of the present invention acquires a first initial entangled group state to be entangled and concentrated, and generates a first auxiliary electronic state according to information of the first initial entangled group state, and then according to the first
  • the polarization beam splitter performs non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state, and determines whether the result of the non-destructive measurement is an odd parity by the charge detector, if non-destructive The result of the measurement is odd parity, then the electrons in the preset spatial mode are processed to obtain the maximum entangled group state.
  • the second polarization beam splitter If the result of the non-destructive measurement is even parity, the same is performed by the second polarization beam splitter. Two electrons in spatial mode are divided into two empty In the inter-mode, the electrons in the pre-set spatial mode are processed, and the second initial entangled group state is obtained for the next round of entanglement and concentration processing.
  • the method improves the success probability of entanglement concentration and the utilization of entangled resources, and is suitable for entanglement and concentration of any K particle group state, and has high availability and adaptability.
  • the present invention also provides an electronic group entanglement concentrating device.
  • 6 is a schematic structural view of an electronic group entanglement concentrating device according to an embodiment of the present invention. As shown in FIG. 6, the electronic group entanglement concentrating device comprises: a generating module 610, a measuring module 620, a determining module 630, a first processing module 640 and a second processing module 650.
  • the generating module 610 is configured to obtain a first initial entangled group state to be entangled and concentrated, and generate a first auxiliary electronic state according to the information of the first initial entangled group state.
  • the generating module 610 may obtain a first initial entangled group state to be entangled and condensed, and generate a first auxiliary electronic state according to the information of the first initial entangled group state, so as to further perform the first initial entangled group state. Entangled concentration treatment.
  • the measuring module 620 is configured to perform non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state according to the first polarization beam splitter.
  • the determining module 630 is configured to determine, by the charge detector, whether the result of the non-destructive measurement is an odd parity.
  • the electronic group state is divided into an odd parity and an even parity to perform entanglement and concentration processing, respectively, thereby realizing the process of entanglement and concentration of the entire electronic group. Therefore, before concentrating the first initial entangled group state, it is necessary to distinguish the odd parity and the even parity.
  • the measurement module 620 performs non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state according to the first polarization beam splitter, that is, the first auxiliary electronic state and the first initial entangled group.
  • the spin freedom of the first electron in the state is processed.
  • the determining module 630 determines whether the entangled state is an odd parity by the number of electrons detected by the charge detector.
  • the first processing module 640 is configured to process the electrons in the preset spatial mode to obtain the maximum entangled group state when the result of the non-destructive measurement is an odd parity.
  • the entangled group state of the odd parity can be entangled and concentrated by the first processing module 640 to obtain the maximum entangled state.
  • FIG. 7 is a schematic structural diagram of an electronic group entanglement concentrating device according to an embodiment of the present invention.
  • the first processing module 640 includes: a first transform unit, as shown in FIG. 641 and first acquisition unit 642. If the result of the non-destructive measurement is an odd parity, the first transform unit 641 The Hadamard transform operation may be performed on the electrons of the preset spatial mode, and the first obtaining unit 642 detects whether the electron spin state after the Hadamard transform operation is a spin-up state, and obtains the maximum entangled group state according to the detection result.
  • the first obtaining unit 642 detects that the learned electron spin state is a spin-up state, the first maximum entangled group state is acquired. If the first obtaining unit 642 detects that the known electronic spin state is a spin-down state, a phase inversion operation is performed to obtain a maximum entangled group state.
  • a second processing module 650 configured to: when the result of the non-destructive measurement is an even parity, the two electrons in the same spatial mode are divided into two spatial modes by the second polarizing beam splitter, and After the separation, the electrons of the preset spatial mode are processed, and the second initial entangled group state is obtained for the next round of entanglement and concentration processing.
  • the second processing module 650 needs to divide the two electrons in the same spatial mode into two spatial modes by the second polarization beam splitter, and after separation The electrons of the preset space mode are processed to obtain the second initial entangled group state for the next round of entanglement and concentration processing.
  • FIG. 8 is a schematic structural diagram of an electronic group entanglement concentrating device according to another embodiment of the present invention.
  • the second processing module 650 includes: The second transform unit 651, the second acquisition unit 652, and the generation unit 653.
  • the second transform unit 651 performs a Hadamard transform operation on the electrons of the separated preset spatial mode, and the second obtaining unit 652 detects whether the electron spin state after the Hadamard transform operation is a spin-up state, and acquires the second initial entangled group according to the detection result.
  • a state that is, if the second obtaining unit 652 detects that the learned electron spin state is a spin-up state, acquiring a second initial entangled group state, and if the second acquiring unit 652 detects that the learned electron spin state is a spin-down state, Perform a phase flip operation to obtain a second initial entangled group state.
  • the generating unit 653 generates a second auxiliary electronic state based on the information of the second initial entangled group state to perform the next round of entanglement concentration processing.
  • the electronic group entanglement concentrating device of the embodiment of the present invention acquires a first initial entangled group state to be entangled and concentrated, and generates a first auxiliary electronic state according to information of the first initial entangled group state, and then according to the first
  • the polarization beam splitter performs non-destructive measurement on the first auxiliary electronic state and the first electron in the first initial entangled group state, and determines whether the result of the non-destructive measurement is an odd parity by the charge detector, if non-destructive The result of the measurement is odd parity, then the electrons in the preset spatial mode are processed to obtain the maximum entangled group state.
  • the second polarization beam splitter If the result of the non-destructive measurement is even parity, the same is performed by the second polarization beam splitter.
  • the two electrons in the spatial mode are divided into two spatial modes, and the electrons in the pre-set spatial mode are processed to obtain the second initial entangled group state for the next round of entanglement and concentration processing.
  • the device improves the success probability of entanglement concentration and the utilization of entangled resources, and is suitable Used for entanglement and concentration of any K particle group, high availability and adaptability.
  • Each module or unit in the above electronic group entanglement concentrating device may pass through one or more digital signal processors (DSPs), application specific integrated circuits (ASICs), processors, microprocessors, controllers, microcontrollers, and field devices.
  • DSPs digital signal processors
  • ASICs application specific integrated circuits
  • processors microprocessors
  • controllers microcontrollers
  • field devices field devices.
  • FPGA programming array
  • programmable logic device or other electronic unit, or any combination thereof.
  • an embodiment of the present invention further provides an electronic group entanglement concentrating device, for example, the device can be applied to a quantum communication device, including:
  • a memory for storing processor executable instructions
  • processor is configured to:
  • the electrons in the preset spatial mode are processed to obtain the maximum entangled group state
  • the two electrons in the same spatial mode are split into two spatial modes by the second polarizing beam splitter, and the electrons in the preset spatial mode are separated. Processing is performed to obtain a second initial entangled group state for the next round of entanglement concentration processing.
  • the method and device of the present application can be applied to the field of quantum communication, and can be mainly applied to the improvement of the success probability of entanglement and concentration of electronic groups.
  • first and second are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated.
  • features defining “first” or “second” may include at least one of the features, either explicitly or implicitly.
  • the meaning of "a plurality” is at least two, such as two, three, etc., unless specifically defined otherwise.

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Abstract

本发明提出了一种电子群态纠缠浓缩方法和装置。其中，方法包括：获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态；根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量；通过电荷探测器判断非破坏性测量的结果是否为奇宇称；如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态；如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。该方法提高了电子群态纠缠浓缩的成功概率。

Description

电子群态纠缠浓缩方法和装置
本申请基于申请号为CN 201610304575.1、申请日为2016年5月10日的中国专利申请提出，并要求该中国专利申请的优先权，该中国专利申请的全部内容在此引入本申请作为参考。
技术领域
本发明涉及通信技术领域，尤其涉及一种电子群态纠缠浓缩方法和装置。
背景技术
无论是在量子通信还是在量子计算中，最大纠缠群态都扮演着非常重要的角色。在实际的应用中，事先制备的最大纠缠群态不可避免的会与周围的环境发生相互作用产生退相干，由最大纠缠群态变为混合态或非最大纠缠纯态。
因此，为了保证量子通信或量子计算的顺利进行，需要对其初始纠缠群态进行纠缠纯化或纠缠浓缩。纠缠纯化是为了从混合态中提取出想要的最大纠缠态。纠缠浓缩则是从非最大纠缠纯态来获得最大纠缠态。
相关技术中，在2004年Beenakker等人的工作打破了不可行定理的壁垒的基础上，将2013年Choudhury提出的一个光子群态的纠缠浓缩方案应用于电子群态的纠缠浓缩，以成功的完成电子群态的纠缠浓缩。但是，该方案对于初始电子纠缠群态的利用率以及纠缠浓缩的成功概率都不够高，且其推广方案只能应用于任意偶数2N粒子电子群态的情况，适用性不强。
发明内容
本发明的目的旨在至少在一定程度上解决上述的技术问题之一。
为此，本发明的第一个目的在于提出一种电子群态纠缠浓缩方法，该方法提高了电子群态纠缠浓缩的成功概率。
本发明的第二个目的在于提出一种电子群态纠缠浓缩装置。
为了实现上述目的，本发明第一方面实施例的电子群态纠缠浓缩方法，包括以下步骤：获取待进行纠缠浓缩的第一初始纠缠群态，根据所述第一初始纠缠群态的信息生成第一辅助电子态；根据第一极化分束器对所述第一辅助电子态和所述第一初始纠 缠群态中的第一电子进行非破坏性测量；通过电荷探测器判断非破坏性测量的结果是否为奇宇称；如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态；如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
根据本发明实施例的电子群态纠缠浓缩方法，获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态，进而根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量，通过电荷探测器判断非破坏性测量的结果是否为奇宇称，如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态，如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。该方法提高了纠缠浓缩的成功概率以及纠缠资源的利用率，且适用于任意K粒子群态的纠缠浓缩，可用性以及适应性高。
另外，在本发明的实施例中，所述对预设空间模式的电子进行处理，获取最大纠缠群态，包括：对预设空间模式的电子进行Hadamard变换操作；检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取最大纠缠群态。
在本发明的实施例中，所述根据检测结果获取最大纠缠群态，包括：如果检测获知电子自旋状态为自旋向上态，则获取第一最大纠缠群态；如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取最大纠缠群态。
在本发明的实施例中，所述对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理，包括：对分离后预设空间模式的电子进行Hadamard变换操作；检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取第二初始纠缠群态；根据所述第二初始纠缠群态的信息生成第二辅助电子态，以便进行下一轮纠缠浓缩处理。
在本发明的实施例中，所述根据检测结果获取第二初始纠缠群态，包括：如果检测获知电子自旋状态为自旋向上态，则获取第二初始纠缠群态；如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取第二初始纠缠群态。
为了实现上述目的，本发明第二方面实施例的电子群态纠缠浓缩装置，包括：生成模块，用于获取待进行纠缠浓缩的第一初始纠缠群态，根据所述第一初始纠缠群态 的信息生成第一辅助电子态；测量模块，用于根据第一极化分束器对所述第一辅助电子态和所述第一初始纠缠群态中的第一电子进行非破坏性测量；判断模块，用于通过电荷探测器判断非破坏性测量的结果是否为奇宇称；第一处理模块，用于在非破坏性测量的结果为奇宇称时，对预设空间模式的电子进行处理，获取最大纠缠群态；第二处理模块，用于在非破坏性测量的结果为偶宇称时，通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
根据本发明实施例的电子群态纠缠浓缩装置，获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态，进而根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量，通过电荷探测器判断非破坏性测量的结果是否为奇宇称，如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态，如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。该装置提高了纠缠浓缩的成功概率以及纠缠资源的利用率，且适用于任意K粒子群态的纠缠浓缩，可用性以及适应性高。
另外，在本发明的实施例中，所述第一处理模块包括：第一变换单元，用于对预设空间模式的电子进行Hadamard变换操作；第一获取单元，用于检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取最大纠缠群态。
在本发明的实施例中，所述第一获取单元用于：在检测获知电子自旋状态为自旋向上态时，获取第一最大纠缠群态；在检测获知电子自旋状态为自旋向下态时，进行相位翻转操作，获取最大纠缠群态。
在本发明的实施例中，所述第二处理模块，包括：第二变换单元，用于对分离后预设空间模式的电子进行Hadamard变换操作；第二获取单元，用于检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取第二初始纠缠群态；生成单元，用于根据所述第二初始纠缠群态的信息生成第二辅助电子态，以便进行下一轮纠缠浓缩处理。
在本发明的实施例中，所述第二获取单元用于：在检测获知电子自旋状态为自旋向上态时，获取第二初始纠缠群态；在检测获知电子自旋状态为自旋向下态时，进行相位翻转操作，获取第二初始纠缠群态。
本发明附加的方面和优点将在下面的描述中部分给出，部分将从下面的描述中变得明显，或通过本发明的实践了解到。
附图说明
本发明上述的和/或附加的方面和优点从下面结合附图对实施例的描述中将变得明显和容易理解，其中，
图1是根据本发明一个实施例的电子群态纠缠浓缩方法的流程图；
图2是根据本发明一个实施例的电子群态非破坏性测量的原理示意图；
图3是根据本发明一个具体实施例的电子群态纠缠浓缩方法的流程图；
图4是根据本发明一个具体实施例的电子群态纠缠浓缩方法的原理图；
图5是循环浓缩的成功概率与初始态系数α、粒子数K以及循环浓缩次数n之间的关系示意图；
图6是根据本发明一个实施例的电子群态纠缠浓缩装置的结构示意图；
图7是根据本发明一个具体实施例的电子群态纠缠浓缩装置结构示意图；以及
图8是根据本发明另一个实施例的电子群态纠缠浓缩装置的结构示意图。
具体实施方式
下面详细描述本发明的实施例，所述实施例的示例在附图中示出，其中自始至终相同或类似的标号表示相同或类似的元件或具有相同或类似功能的元件。下面通过参考附图描述的实施例是示例性的，旨在用于解释本发明，而不能理解为对本发明的限制。
下面参考附图描述本发明实施例的电子群态纠缠浓缩方法和装置。
图1是根据本发明一个实施例的电子群态纠缠浓缩方法的流程图。如图1所示，该电子群态纠缠浓缩方法包括：
S110，获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态。
在进行纠缠浓缩处理之前，需要获取用于量子纠缠或量子计算的初始纠缠资源，该初始纠缠群态为非最大纠缠群态。
另外，为了实现本发明实施例的电子群态纠缠浓缩方法，还需要生成的依赖于初始纠缠群态的信息的辅助电子态，且在每一轮纠缠浓缩的初始阶段，都需要制备与该 次纠缠群态的状态对应辅助电子态。
具体地，可获取待进行纠缠浓缩的第一初始纠缠群态，并根据该第一初始纠缠群态的信息生成第一辅助电子态，以便于进一步地对第一初始纠缠群态进行纠缠浓缩处理。
S120，根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量。
S130，通过电荷探测器判断非破坏性测量的结果是否为奇宇称。
在本发明的实施例中，将电子群态分为奇宇称和偶宇称分别进行纠缠浓缩处理，从而实现对整个电子群态纠缠浓缩的处理。因此，在对第一初始纠缠群态浓缩之前，需要区分出其中的奇宇称和偶宇称。
首先，根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量，即对第一辅助电子态和第一初始纠缠群态中的第一电子的自旋自由度进行处理。
其中，需要说明的是，由于电子在电子自由度和自旋自由度上显示相互独立的，当使用电荷探测器探测电子系统的电荷数时，该电子系统的自旋自由度不会受到任何影响。同样的，对于电子系统的自旋自由度进行操作，也不会影响它的电荷数。因此第一极化分束器对第一电子的测量过程是非破坏性的。
进而，在进行非破坏性测量后，通过电荷探测器探测到的电子数，判断该纠缠态是否是奇宇称。
为了更加清楚的描述本发明实施例的电子非破坏性测量原理，下面结合附图2进行说明，说明如下：
图2是根据本发明一个实施例的电子群态非破坏性测量的原理示意图，如图2所示，通过第一极化分束器PBS对第一辅助电子态和第一初始纠缠群态中的第一电子a和b进行非破坏性测量。
输入第一电子a和b在自旋自由度上分别可能为自旋向上态|↑>和自旋向下态|↓>，即a，b有四种可能的自旋组合。当第一电子通过极化分束器时，自旋向上电子将会被完全透射。相反的，自旋向下电子在通过极化分束器时将会被完全反射。对于输入的第一电子a,b，经过第一极化分束器后其a1,b1的输出形式分别为：
Figure PCTCN2016099535-appb-000001
Figure PCTCN2016099535-appb-000002
Figure PCTCN2016099535-appb-000003
Figure PCTCN2016099535-appb-000004
很明显，通过第一极化分束器后，在空间模式上可以将它们分为两类。一类是，在空间模式a1，b1上分别有且只有一个电子。另一类是，在空间模式a1(b1)上有两个电子，空间模式b1(a1)没有电子。
因此，在电荷探测器P的测量下会得到不同的电荷数。初始电子自旋态为|↑>a|↑>b和|↓>a|↓>b时，电荷探测器P测量的电荷数为1。初始电子自旋态为|↑>a|↓>b时，电荷探测器P测量的电荷数为2。相反的，初始电子自旋态为|↓>a|↑>b时，电荷探测器P测量的电荷数为0。利用电荷探测器P的测量结果，经过第一极化分束器后的第一初始纠缠群态会被分为两类。与此同时，第一初始纠缠群态的自旋自由度不会受到任何的影响，这样就完成了电子的非破坏性测量。
S140，如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态。
在本发明的实施例中，如果非破坏性测量的结果为奇宇称，则可通过对奇宇称的纠缠群态进行纠缠浓缩处理，获取最大纠缠态。
具体地，如果非破坏性测量的结果为奇宇称，则可对预设空间模式的电子进行Hadamard变换操作，检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取最大纠缠群态。
更具体地，如果检测获知电子自旋状态为自旋向上态，则获取第一最大纠缠群态。如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取最大纠缠群态。
S150，如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
可以理解，在步骤S140后，已经成功的完成了一轮纠缠浓缩处理过程。但是，在非破坏性测量之后，只挑选出了奇宇称的情况，而将偶宇称的情况视为“失败”。这对于纠缠浓缩的成功概率以及资源的利用率都相对较低。
在本发明的实施例中，为了提高纠缠浓缩的成功概率以及资源的利用率，如果非 破坏性测量的结果为偶宇称，则将偶宇称的纠缠态作为下一次纠缠浓缩处理的初始纠缠群态资源，并对偶宇称的纠缠态进性循环地纠缠浓缩处理。
具体地，为了实现对偶宇称的纠缠浓缩处理，需要通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
具体而言，对分离后预设空间模式的电子进行Hadamard变换操作，检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取第二初始纠缠群态，即如果检测获知电子自旋状态为自旋向上态，则获取第二初始纠缠群态，如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取第二初始纠缠群态。
并且，根据第二初始纠缠群态的信息生成第二辅助电子态，以便进行下一轮纠缠浓缩处理。
基于以上实施例，可以发现,得到的第二初始纠缠群态，拥有与第一初始纠缠群态完全相同的形式。从而可将第二初始纠缠群态作为下一轮纠缠浓缩的初始纠缠群态。因此，可以通过不断的重复纠缠浓缩过程可以达到一个更高的纠缠浓缩的成功概率。循环n轮的总的成功概率为：
Figure PCTCN2016099535-appb-000005
可以看出，总的成功概率只与初始态的系数和浓缩进行的轮数n有关。
为了更加清楚的描述本发明的电子群态纠缠浓缩方法，下面结合附图3和附图4，以第一初始电子群态为四粒子群态为例，详细说明本发明实施例的电子群态纠缠浓缩方法。
其中，图3是电子群态纠缠浓缩方法的流程图，图4是电子群态纠缠浓缩方法的原理图，说明如下：
S310，获取初始非最大纠缠群态和辅助电子态。
具体地，在进行纠缠浓缩处理之前，需要准备初始的纠缠群态资源，以及与初始非最大纠缠群态对应的辅助电子态。
如图4所示，获取待纠缠浓缩处理的非最大纠缠群态的四粒子群态，即获取a,b,c和d四个粒子的纠缠群态，该四粒子群态具有如下一般形式：
Figure PCTCN2016099535-appb-000006
其中，系数α和β满足归一化条件，即2(|α|2+|β|2)＝1。下标的a,b,c,d表示的是群态的粒子由不同的四方拥有。
在对该四粒子群态进行浓缩之前，需要通过Dick引入一个空间模式为e的辅助电子态，该辅助电子台依赖于四粒子群态，且该辅助电子的形式为：
Figure PCTCN2016099535-appb-000007
S320，进行非破坏性测量。
S330，判断非破坏性测量的结果是否为奇宇称。
具体地，通过电荷探测器判断非破坏性测量的结果是否为奇宇称。如图4所示，通过第一极化分束器PBS1对电子d和e进行非破坏性测量，并通过电荷探测器P探测经过PBS1处理后的电子(d1和e1)的电荷,判断是否是奇宇称。
S340，如果是奇宇称，则对预设空间模式的电子进行Hadamard变换操作。
根据非破坏性测量结果，挑选出空间模式d和e为|↑>d|↑>e或|↓>d|↓>e的所有情况，也就是奇宇称的情况，则可以得到如下纠缠态：
Figure PCTCN2016099535-appb-000008
这一步的成功概率为：P1＝8|αβ|2。
进而，Dick对其所拥有的空间模式为f2的电子做一个Hadamard操作。Hadamard操作对于电子自旋态的作用是使
Figure PCTCN2016099535-appb-000009
和
Figure PCTCN2016099535-appb-000010
对其操作完后，可以得到如下纠缠态：
Figure PCTCN2016099535-appb-000011
S350，检测电子自旋状态是否为自旋向上态。
具体地，检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，Dick利用电荷探测器探测其空间模式为f3的电子。测量结果只有两种可能，即自旋向上态或自旋向下态。
S360，如果检测获知电子自旋状态为自旋向上态，则获取第一最大纠缠群态。
具体地，当测量结果为自旋向上态|↑>f3时，直接可以得到最大纠缠群态：
Figure PCTCN2016099535-appb-000012
S370，如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取最大纠缠群态。
具体地，当电荷探测器测量结果为自旋向下态|↓>f3时，可以获得如下形式的纠缠态：
Figure PCTCN2016099535-appb-000013
进而，对其进行一个相位翻转操作即可得到与测量结果为自旋向上态时同样的最大纠缠态。
S380，如果非破坏性测量的结果不是奇宇称，则通过第二极化分束器对其进行处理。
在本实施例中，为了提高电子群态纠缠浓缩的成功概率，将电荷探测器探测到0个 或2个电荷的情况下的纠缠态能够被当作下一轮纠缠浓缩过程的初始纠缠态。
具体而言，将偶宇称情况挑选出来，即空间模式d和e中电子为|↑>d|↓>e或|↑>d|↓>e的情况，可以得到如下纠缠态：
Figure PCTCN2016099535-appb-000014
获得该纠缠态的概率为：
P′1＝4(|α|4+|β|4)
可以发现，在此情况下经过极化分束器后，Dick所拥有的两个电子总是在同一空间模式上。为了使其能作为下一轮浓缩的初始纠缠态，需要确保这两个电子在不同的空间模式上。
为了将这两个电子从同一空间模式分开，如图4所示，引入另一个极化分束器PBS2。让空间模式为f1和f2的电子经过第二个极化分束器，确保在空间模式f3和f4上分别有且只有一个电子，形式如下：
Figure PCTCN2016099535-appb-000015
S390，对分离后预设空间模式的电子进行Hadamard变换操作。
具体地，对空间模式为f4的电子进行一个Hadamard操作，并对其进行测量。
S3100，检测电子自旋状态是否为自旋向上态。
具体地，检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态。
S3110，如果检测获知电子自旋状态为自旋向上态，则获取第二初始纠缠群态。
具体地，当测量结果为自旋向上态时，得到如下纠缠态，其系数满足归一化条件，从而获取到第二初始纠缠群态。
Figure PCTCN2016099535-appb-000016
S3120，如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取第二初始纠缠群态。
具体地，当测量结果为自旋向下态时，得到如下纠缠态，
Figure PCTCN2016099535-appb-000017
从而对其进行相位翻转操作，获取第二初始纠缠群态。
S3130，生成与第二初始纠缠群态对应的辅助电子态。
具体地，获取第二初始纠缠群态后，生成其对应的辅助电子态，并执行步骤S320，以进行下一轮的纠缠浓缩处理。
然而，需要说明的是，以上结合图3与图4说明的电子群态纠缠浓缩方法，是建立在四粒子群态的基础上的，该方法也可以应用于任意K粒子群态的情况。
电子自旋任意K粒子群态的纠缠态形式如下：
Figure PCTCN2016099535-appb-000018
为了便于说明，可以假设Dick拥有下标为K的电子。依据相同的原理，Dick首先需要制备一个辅助电子，其形式为：
Figure PCTCN2016099535-appb-000019
对K粒子群态，经过n轮循环浓缩后，其总的成功概率为：
Figure PCTCN2016099535-appb-000020
图5是循环浓缩的成功概率与初始态系数α、粒子数K以及循环浓缩次数n之间的关系示意图，由图5所示，在循环浓缩处理次数较高的时候，对任意K粒子群态纠缠浓缩处理的成功率较高。
因此上面描述电子群态纠缠浓缩的实现方案，不仅可用于四粒子群态的纠缠浓缩，同样适用于任意K粒子群态的情况。
综上所述，本发明实施例的电子群态纠缠浓缩方法，获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态，进而根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量，通过电荷探测器判断非破坏性测量的结果是否为奇宇称，如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态，如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空 间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。该方法提高了纠缠浓缩的成功概率以及纠缠资源的利用率，且适用于任意K粒子群态的纠缠浓缩，可用性以及适应性高。
为了实现上述目的，本发明还提出了一种电子群态纠缠浓缩装置。图6是根据本发明一个实施例的电子群态纠缠浓缩装置的结构示意图。如图6所示，该电子群态纠缠浓缩装置包括：生成模块610、测量模块620、判断模块630、第一处理模块640和第二处理模块650。
其中，生成模块610用于获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态。
具体地，生成模块610可获取待进行纠缠浓缩的第一初始纠缠群态，并根据该第一初始纠缠群态的信息生成第一辅助电子态，以便于进一步地对第一初始纠缠群态进行纠缠浓缩处理。
测量模块620，用于根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量。
判断模块630，用于通过电荷探测器判断非破坏性测量的结果是否为奇宇称。
在本发明的实施例中，将电子群态分为奇宇称和偶宇称分别进行纠缠浓缩处理，从而实现对整个电子群态纠缠浓缩的处理。因此，在对第一初始纠缠群态浓缩之前，需要区分出其中的奇宇称和偶宇称。
首先，测量模块620根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量，即对第一辅助电子态和第一初始纠缠群态中的第一电子的自旋自由度进行处理。
进而，在进行非破坏性测量后，判断模块630通过电荷探测器探测到的电子数，判断该纠缠态是否是奇宇称。
第一处理模块640，用于在非破坏性测量的结果为奇宇称时，对预设空间模式的电子进行处理，获取最大纠缠群态。
在本发明的实施例中，如果非破坏性测量的结果为奇宇称，则可通过第一处理模块640对奇宇称的纠缠群态进行纠缠浓缩处理，获取最大纠缠态。
具体地，图7是根据本发明一个具体实施例的电子群态纠缠浓缩装置结构示意图，如图7所示，在如图6所示的基础上，第一处理模块640包括：第一变换单元641和第一获取单元642。如果非破坏性测量的结果为奇宇称，则第一变换单元641 可对预设空间模式的电子进行Hadamard变换操作，第一获取单元642检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取最大纠缠群态。
更具体地，如果第一获取单元642检测获知电子自旋状态为自旋向上态，则获取第一最大纠缠群态。如果第一获取单元642检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取最大纠缠群态。
第二处理模块650，用于在非破坏性测量的结果为偶宇称时，通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
具体地，为了实现对偶宇称的纠缠浓缩处理，第二处理模块650需要通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
具体而言，图8是根据本发明另一个实施例的电子群态纠缠浓缩装置的结构示意图，如图8所示，在如图6所示的基础上，该第二处理模块650包括：第二变换单元651、第二获取单元652和生成单元653。
第二变换单元651对分离后预设空间模式的电子进行Hadamard变换操作，第二获取单元652检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取第二初始纠缠群态，即如果第二获取单元652检测获知电子自旋状态为自旋向上态，则获取第二初始纠缠群态，如果第二获取单元652检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取第二初始纠缠群态。
并且，生成单元653根据第二初始纠缠群态的信息生成第二辅助电子态，以便进行下一轮纠缠浓缩处理。
综上所述，本发明实施例的电子群态纠缠浓缩装置，获取待进行纠缠浓缩的第一初始纠缠群态，根据第一初始纠缠群态的信息生成第一辅助电子态，进而根据第一极化分束器对第一辅助电子态和第一初始纠缠群态中的第一电子进行非破坏性测量，通过电荷探测器判断非破坏性测量的结果是否为奇宇称，如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态，如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。该装置提高了纠缠浓缩的成功概率以及纠缠资源的利用率，且适 用于任意K粒子群态的纠缠浓缩，可用性以及适应性高。
上述电子群态纠缠浓缩装置中的各个模块或单元可以通过一个或多个数字信号处理器(DSP)、专用集成电路(ASIC)、处理器、微处理器、控制器、微控制器、现场可编程阵列(FPGA)、可编程逻辑器件或其他电子单元或其任意组合来实现。在本申请实施例中描述的一些功能或处理也可以通过在处理器上执行的软件来实现。
例如，本发明的实施例还提供了一种电子群态纠缠浓缩装置，例如该装置可以应用于一量子通信设备中，包括：
处理器；
用于存储处理器可执行指令的存储器；
其中，所述处理器被配置为：
获取待进行纠缠浓缩的第一初始纠缠群态，根据所述第一初始纠缠群态的信息生成第一辅助电子态；
根据第一极化分束器对所述第一辅助电子态和所述第一初始纠缠群态中的第一电子进行非破坏性测量；
通过电荷探测器判断非破坏性测量的结果是否为奇宇称；
如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态；
如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
工业实用性
本申请的方法和装置可应用于量子通信领域中，主要可应用于电子群态纠缠浓缩成功概率的提高。
此外，术语“第一”、“第二”仅用于描述目的，而不能理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括至少一个该特征。在本发明的描述中，“多个”的含义是至少两个，例如两个，三个等，除非另有明确具体的限定。
在本说明书的描述中，参考术语“一个实施例”、“一些实施例”、“示例”、“具体示例”、或“一些示例”等的描述意指结合该实施例或示例描述的具体特征、 结构、材料或者特点包含于本发明的至少一个实施例或示例中。在本说明书中，对上述术语的示意性表述不必须针对的是相同的实施例或示例。而且，描述的具体特征、结构、材料或者特点可以在任一个或多个实施例或示例中以合适的方式结合。此外，在不相互矛盾的情况下，本领域的技术人员可以将本说明书中描述的不同实施例或示例以及不同实施例或示例的特征进行结合和组合。
尽管上面已经示出和描述了本发明的实施例，可以理解的是，上述实施例是示例性的，不能理解为对本发明的限制，本领域的普通技术人员在本发明的范围内可以对上述实施例进行变化、修改、替换和变型。

Claims (10)

  1. 一种电子群态纠缠浓缩方法，其中，包括以下步骤：
    获取待进行纠缠浓缩的第一初始纠缠群态，根据所述第一初始纠缠群态的信息生成第一辅助电子态；
    根据第一极化分束器对所述第一辅助电子态和所述第一初始纠缠群态中的第一电子进行非破坏性测量；
    通过电荷探测器判断非破坏性测量的结果是否为奇宇称；
    如果非破坏性测量的结果为奇宇称，则对预设空间模式的电子进行处理，获取最大纠缠群态；
    如果非破坏性测量的结果为偶宇称，则通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
  2. 如权利要求1所述的方法，其中，所述对预设空间模式的电子进行处理，获取最大纠缠群态，包括：
    对预设空间模式的电子进行Hadamard变换操作；
    检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取最大纠缠群态。
  3. 如权利要求2所述的方法，其中，所述根据检测结果获取最大纠缠群态，包括：
    如果检测获知电子自旋状态为自旋向上态，则获取第一最大纠缠群态；
    如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取最大纠缠群态。
  4. 如权利要求1所述的方法，其中，所述对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理，包括：
    对分离后预设空间模式的电子进行Hadamard变换操作；
    检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取第二初始纠缠群态；
    根据所述第二初始纠缠群态的信息生成第二辅助电子态，以便进行下一轮纠缠浓缩处理。
  5. 如权利要求4所述的方法，其中，所述根据检测结果获取第二初始纠缠群态， 包括：
    如果检测获知电子自旋状态为自旋向上态，则获取第二初始纠缠群态；
    如果检测获知电子自旋状态为自旋向下态，则进行相位翻转操作，获取第二初始纠缠群态。
  6. 一种电子群态纠缠浓缩装置，其中，包括：
    生成模块，设置为获取待进行纠缠浓缩的第一初始纠缠群态，根据所述第一初始纠缠群态的信息生成第一辅助电子态；
    测量模块，设置为根据第一极化分束器对所述第一辅助电子态和所述第一初始纠缠群态中的第一电子进行非破坏性测量；
    判断模块，设置为通过电荷探测器判断非破坏性测量的结果是否为奇宇称；
    第一处理模块，设置为在非破坏性测量的结果为奇宇称时，对预设空间模式的电子进行处理，获取最大纠缠群态；
    第二处理模块，设置为在非破坏性测量的结果为偶宇称时，通过第二极化分束器使在同一个空间模式的两个电子被分到两个空间模式上，并对分离后预设空间模式的电子进行处理，获取第二初始纠缠群态进行下一轮纠缠浓缩处理。
  7. 如权利要求6所述的装置，其中，所述第一处理模块包括：
    第一变换单元，设置为对预设空间模式的电子进行Hadamard变换操作；
    第一获取单元，设置为检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取最大纠缠群态。
  8. 如权利要求7所述的装置，其中，所述第一获取单元设置为：
    在检测获知电子自旋状态为自旋向上态时，获取第一最大纠缠群态；
    在检测获知电子自旋状态为自旋向下态时，进行相位翻转操作，获取最大纠缠群态。
  9. 如权利要求6所述的装置，其中，所述第二处理模块，包括：
    第二变换单元，设置为对分离后预设空间模式的电子进行Hadamard变换操作；
    第二获取单元，设置为检测经过Hadamard变换操作的电子自旋状态是否为自旋向上态，根据检测结果获取第二初始纠缠群态；
    生成单元，用于根据所述第二初始纠缠群态的信息生成第二辅助电子态，以便进行下一轮纠缠浓缩处理。
  10. 如权利要求9所述的装置，其中，所述第二获取单元设置为：
    在检测获知电子自旋状态为自旋向上态时，获取第二初始纠缠群态；
    在检测获知电子自旋状态为自旋向下态时，进行相位翻转操作，获取第二初始纠缠群态。
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US20080232814A1 (en) * 2002-10-02 2008-09-25 Kabushiki Kaisha Toshiba Quantum communication apparatus and quantum communication method
CN101401116A (zh) * 2005-08-12 2009-04-01 惠普开发有限公司 量子中继器
CN102577225A (zh) * 2009-06-30 2012-07-11 惠普开发有限公司 量子中继器以及用于创建扩展纠缠的系统和方法
CN103825732A (zh) * 2014-03-14 2014-05-28 浙江工商大学 抗集体退相位噪声的无信息泄露量子对话协议

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US20080232814A1 (en) * 2002-10-02 2008-09-25 Kabushiki Kaisha Toshiba Quantum communication apparatus and quantum communication method
CN101401116A (zh) * 2005-08-12 2009-04-01 惠普开发有限公司 量子中继器
CN102577225A (zh) * 2009-06-30 2012-07-11 惠普开发有限公司 量子中继器以及用于创建扩展纠缠的系统和方法
CN103825732A (zh) * 2014-03-14 2014-05-28 浙江工商大学 抗集体退相位噪声的无信息泄露量子对话协议

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