CN115994580B - A method and device for constructing a quantum logic gate - Google Patents

Abstract

Disclosed herein is a method and apparatus for constructing a quantum logic gate, comprising: performing phase modulation on the first continuous laser by an electro-optical modulator (EOM) with preset driving frequency to obtain second continuous laser which comprises two frequency components and is used for constructing a quantum logic gate; constructing a quantum logic gate through the obtained second continuous laser; wherein the quantum logic gate comprises: single bit quantum logic gates and double bit quantum logic gates. The second continuous laser obtained through phase modulation in the embodiment of the invention simultaneously realizes the single-bit quantum logic gate and the double-bit quantum logic gate which are not influenced by phase noise, the number of the quantum logic gates is not limited by laser coherence time any more, and a foundation is provided for realizing large-scale quantum computation.

Description

A method and device for constructing a quantum logic gate

Technical Field

This article relates to but is not limited to quantum computing technology, and in particular to a method and device for constructing quantum logic gates.

Background technique

A quantum computer is a device that uses quantum logic to perform general calculations. The basic logic unit of a quantum computer is composed of quantum bits that obey the principles of quantum mechanics. A large number of interacting quantum bits can physically realize a quantum computer. Compared with traditional computers, quantum computers can significantly reduce the computing time when solving certain problems. Quantum computers have broad application prospects in future basic scientific research, quantum communications and cryptography, artificial intelligence, financial market simulation, and climate change prediction, and therefore have received widespread attention.

Using an array of ion qubits trapped in a potential well, high-fidelity quantum logic gate operations can be achieved under existing experimental conditions; ion qubits have excellent performance in key indicators that measure quantum computing performance, such as interaction control, long coherence time, high-fidelity quantum logic gate operations, and quantum error correction, and are one of the most likely platforms for realizing quantum computers.

The construction of quantum logic gates (including single-bit quantum logic gates and two-bit quantum logic gates) is an indispensable step in realizing quantum computing. In the related technologies, quantum logic gates are mainly constructed by utilizing Raman transitions produced by far-detuned lasers or Stark effects produced by near-detuned narrow-linewidth lasers. One or both of the single-bit quantum logic gates and the two-bit quantum logic gates will be affected by laser phase noise. It is impossible to use the same laser to simultaneously realize single-bit quantum logic gates and two-bit quantum logic gates that are independent of laser phase noise. As a result, the number of high-fidelity quantum logic gates that can be executed is limited by the laser coherence time, and large-scale quantum computing cannot be performed.

Summary of the invention

The following is a summary of the subject matter described in detail herein. This summary is not intended to limit the scope of the claims.

The embodiments of the present invention provide a method and device for constructing a quantum logic gate, which can realize a single-bit quantum logic gate and a dual-bit quantum logic gate that are insensitive to laser phase noise using lasers of the same wavelength.

An embodiment of the present invention provides a method for constructing a quantum logic gate, comprising:

Phase modulating the first continuous laser light by an electro-optic modulator (EOM) with a preset driving frequency to obtain a second continuous laser light containing two frequency components for constructing a quantum logic gate;

Constructing a quantum logic gate using the obtained second continuous laser;

Wherein, the quantum logic gate includes: a single-bit quantum logic gate and a double-bit quantum logic gate.

On the other hand, an embodiment of the present invention further provides a device for constructing a quantum logic gate, comprising: a phase modulation unit and a construction unit; wherein,

The phase modulation unit is configured to: phase-modulate the first continuous laser through an electro-optic modulator EOM with a preset driving frequency to obtain a second continuous laser containing two frequency components for constructing a quantum logic gate;

The construction unit is configured to: construct a quantum logic gate by using the obtained second continuous laser;

Wherein, the quantum logic gate includes: a single-bit quantum logic gate and a double-bit quantum logic gate.

The technical solution of the present application includes: phase modulating the first continuous laser through an electro-optic modulator (EOM) with a preset driving frequency to obtain a second continuous laser containing two frequency components for constructing a quantum logic gate; constructing a quantum logic gate through the obtained second continuous laser; wherein the quantum logic gate includes: a single-bit quantum logic gate and a two-bit quantum logic gate. The second continuous laser obtained by phase modulation in the embodiment of the present invention realizes a single-bit quantum logic gate and a two-bit quantum logic gate that are not affected by phase noise at the same time, and the number of quantum logic gates is no longer limited by the laser coherence time, which provides a basis for realizing large-scale quantum computing.

Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the description, claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are used to provide a further understanding of the technical solution of the present invention and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present invention and do not constitute a limitation on the technical solution of the present invention.

FIG1 is a flow chart of a method for constructing a quantum logic gate according to an embodiment of the present invention;

FIG2 is a schematic diagram of the energy levels of an ion quantum bit of the present invention;

FIG3 is a schematic diagram of the structure of a device for implementing a single-bit quantum logic gate according to an embodiment of the present invention;

FIG4 is a schematic diagram of the composition of a device for implementing a two-bit quantum logic gate according to an embodiment of the present invention;

FIG5 is a structural block diagram of a device for constructing a quantum logic gate according to an embodiment of the present invention.

Detailed ways

In order to make the purpose, technical solution and advantages of the present invention more clear, the embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other arbitrarily without conflict.

The steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions. Also, although a logical sequence is shown in the flowchart, in some cases, the steps shown or described can be performed in a sequence different from that shown here.

FIG1 is a flow chart of a method for constructing a quantum logic gate according to an embodiment of the present invention, as shown in FIG1 , comprising:

Step 101: Phase modulating the first continuous laser by an electro-optic modulator (EOM) with a preset driving frequency to obtain a second continuous laser containing two frequency components for constructing a quantum logic gate;

Step 102, constructing a quantum logic gate by using the obtained second continuous laser;

Among them, quantum logic gates include: single-bit quantum logic gates and double-bit quantum logic gates.

It should be noted that, in the embodiment of the present invention, the driving frequency f _EOM is set, and the center frequency of the first continuous laser is f ₀ , then after the continuous laser is phase modulated by EOM, a sideband component with a frequency of f ₀ ±nf _EOM is generated, wherein n is an integer; the embodiment of the present invention is explained below by constructing a quantum logic gate using two sideband components with n=1; in the process of constructing the quantum logic gate, other sidebands with n not equal to 1 do not participate in and do not affect the construction of the quantum logic gate.

The technical solution of the present application includes: phase modulating the first continuous laser through an electro-optic modulator (EOM) with a preset driving frequency to obtain a second continuous laser containing two frequency components for constructing a quantum logic gate; constructing a quantum logic gate through the obtained second continuous laser; wherein the quantum logic gate includes: a single-bit quantum logic gate and a two-bit quantum logic gate. The second continuous laser obtained by phase modulation in the embodiment of the present invention realizes a single-bit quantum logic gate and a two-bit quantum logic gate that are not affected by laser phase noise at the same time, and the number of quantum logic gates is no longer limited by the laser coherence time, which provides a basis for realizing large-scale quantum computing.

In one exemplary embodiment, the first continuous laser comprises: a nearly detuned continuous laser;

Among them, the difference between the first center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the first excited state energy level is Δf; Δf is less than the first preset value times _fh ; _fh is the frequency difference between two sub-energy levels contained in the quantum bit basis vector; the first excited state energy level includes: the predetermined excited state energy level involved in the energy level transition for constructing a quantum logic gate.

In an exemplary embodiment, the first preset value in the embodiment of the present invention may be equal to 10. It may be adjusted by technicians according to relevant principles of quantum computing.

FIG2 is a schematic diagram of the energy levels of an ion quantum bit of the present invention. As shown in FIG2 , the frequency difference between the two sub-energy levels included in the quantum bit basis vector is f _h .

In the embodiment of the present invention, when Δf is less than the first preset value times f _h , the first center frequency of the first continuous laser meets the near-detuning condition; the second continuous laser based on the phase modulation of the first continuous laser also meets the near-detuning condition.

In an exemplary embodiment, the energy level transition in the embodiment of the present invention includes: electric dipole transition, electric quadrupole transition or electric octet transition.

In an exemplary embodiment, the first continuous laser of the embodiment of the present invention includes: a far-detuned continuous laser;

Among them, the difference between the second center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the second excited state energy level is Δf; Δf is greater than the second preset value times _fh ; _fh is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector; the second excited state energy level includes: the predetermined excited state energy level involved in the energy level transition for constructing a quantum logic gate.

In the embodiment of the present invention, when Δf is greater than the second preset value times f _h , the second center frequency of the first continuous laser meets the far detuning condition; the second continuous laser based on the phase modulation of the first continuous laser also meets the near detuning and far detuning conditions.

In an exemplary embodiment, the second preset value in the embodiment of the present invention can be calculated according to the relevant principles of quantum computing, and the second preset value can be greater than or equal to 10. For example, the second preset value can be 10. The energy level transition in the embodiment of the present invention includes: electric dipole transition, electric quadrupole transition or electric octet transition.

In an exemplary embodiment, before constructing a quantum logic gate by using a second continuous laser obtained from a far-detuned first continuous laser, the method of the embodiment of the present invention further includes:

The second continuous laser light is passed through a preset etalon, so that the intensity of even-order sideband components in the second continuous laser light is lower than the intensity of odd-order sideband components.

In an exemplary embodiment, in an embodiment of the present invention, a second continuous laser can be passed through a Fabry-Perot (FP) etalon so that the even-order sideband components are suppressed, thereby obtaining a second continuous laser whose intensity of the even-order sideband components is lower than that of the odd-order sideband components.

In an exemplary embodiment, the difference between the frequencies of the two frequency components in the second continuous laser light of the embodiment of the present invention is equal to f _h ;

Among them, fh _is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector.

In an exemplary embodiment, when the quantum logic gate in the embodiment of the present invention is a single-bit quantum logic gate, the preset driving frequency f _EOM is equal to f _h /2;

Among them, fh _is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector.

It should be noted that the embodiment of the present invention can perform phase modulation on the first continuous laser based on the EOM of other driving frequencies to obtain a second continuous laser for constructing a quantum logic gate, in which the difference between the frequencies of the two frequency components is equal to f _h .

In an exemplary embodiment, the embodiment of the present invention constructs a quantum logic gate by using the obtained second continuous laser, including:

Adjusting the polarization, light intensity and center frequency of the second continuous laser of a single channel;

The second continuous laser after adjusting the polarization, light intensity and center frequency is irradiated on the quantum bit for a first preset time period to achieve Raman transition between quantum bit basis vectors.

In one embodiment example, the embodiment of the present invention realizes the Raman transition between two sub-energy levels contained in the quantum bit basis vector by adjusting the central frequency, polarization, light intensity and irradiation time of the second continuous laser, that is, realizes a single-bit quantum logic gate.

In an exemplary embodiment, an embodiment of the present invention can adjust the center frequency and power of the second continuous laser through an acousto-optic modulator (AOM), adjust the polarization of the second continuous laser through a wave plate, and finally irradiate it onto the quantum bit, and use the AOM to control the irradiation duration to realize a single-bit quantum logic gate.

FIG3 is a schematic diagram of the structure of an apparatus for realizing a single-bit quantum logic gate according to an embodiment of the present invention. As shown in FIG3 , after the first continuous laser is phase modulated by the EOM, the obtained second continuous laser is passed through the etalon (if the first continuous laser is a far-detuned laser); the center frequency and power of the second continuous laser are adjusted by an acousto-optic modulator (AOM), polarization is adjusted by a wave plate, and finally irradiated onto the quantum bit. The irradiation duration is controlled by the AOM, thereby realizing a single-bit quantum logic gate.

In an exemplary embodiment, when the quantum logic gate in the embodiment of the present invention is a two-bit quantum logic gate, the preset driving frequency f _EOM is equal to f _h /2;

In an exemplary embodiment, the second continuous laser in the embodiment of the present invention includes: a laser that causes unequal Stark level shifts on two sub-energy levels included in the quantum bit basis vector. In other words, those skilled in the art can determine the EOM according to the properties of the second continuous laser that needs to be obtained, and the first continuous laser is phase-modulated by the EOM that determines the driving frequency, so that the second continuous laser causes unequal Stark level shifts on two sub-energy levels included in the quantum bit basis vector.

In an embodiment example, the embodiment of the present invention constructs a quantum logic gate by using the obtained second continuous laser, including:

splitting the second continuous laser into two beams;

adjusting the polarization, center frequency and light intensity of the two second continuous laser beams obtained by splitting;

Two second continuous laser beams with adjusted polarization, center frequency and light intensity are simultaneously irradiated from different directions onto at least two quantum bits that need to construct a quantum logic gate;

Among them, the difference between the center frequencies of the two second continuous laser beams and the eigenfrequency of the collective vibration mode excited by the constructed two-bit quantum logic gate is less than the third preset value times the eigenfrequency.

In an exemplary embodiment, the third preset value of the embodiment of the present invention can be 0.1; in an exemplary embodiment, the third preset value of the embodiment of the present invention can be obtained according to relevant principles of quantum computing, and can be dynamically adjusted in the process of constructing a quantum logic gate.

In an exemplary embodiment, the present invention uses two second continuous lasers, using the Stark level shift method or MS ( and/> The method is to construct a two-bit quantum logic gate by using a method of (a) a person's name and (b) a person's name respectively. In an exemplary embodiment, the propagation direction angle of the two second continuous lasers in the embodiment of the present invention is not equal to zero; for example, the two second continuous lasers irradiate at least two or more quantum bits from opposite directions at the same time. The difference between the center frequencies of the two second continuous lasers is close to the eigenfrequency of the collective vibration mode excited by the two second continuous lasers, and its specific value can be obtained according to the relevant principles of quantum computing.

In an exemplary embodiment, the embodiment of the present invention uses the method of Stark level shift to construct a two-bit quantum logic gate. At this time, the driving frequency of the EOM and the driving frequency of the AOM need to be set to: make the Stark level shifts caused by the second continuous laser on the two sub-energy levels contained in the quantum bit basis vector unequal; split the second continuous laser into two beams, use AOM to adjust the center frequency and power of the two laser beams (dynamically), use wave plates to adjust the polarization of the two laser beams, and finally irradiate them onto the quantum bit at the same time. By controlling the irradiation time of the two laser beams through AOM, a two-bit quantum logic gate can be realized. Specifically, as shown in FIG4 , the center frequency of the first continuous laser in the embodiment of the present invention is f ₀ , and the EOM driving frequency is f _EOM ; the first continuous laser is phase modulated by EOM to obtain a second continuous laser containing two frequency components; if the first continuous laser is a far-detuned laser, the second continuous laser also needs to be frequency screened by an etalon to suppress its even-order sideband components; the second continuous laser is split into a first laser and a second laser, and is driven by AOMs with driving frequencies of f _AOM1 and f _AOM2 , respectively, then the first laser contains two frequency components, respectively The second laser contains two frequency components, namely/> The difference in center frequency between the first laser and the second laser split out in the embodiment of the present invention |f _AOM1 -f _AOM2 | is close to ν, and its specific value can be calculated based on the relevant principles of quantum computing, for example, it is less than 0.1 times ν, and its specific value can be dynamically adjusted according to the actual situation. According to the specific properties of the quantum bit energy level structure, the polarization and power of the two second continuous lasers and the AOM driving frequency are set, so that the center frequency of the first laser The frequency component of the second laser is the same as that of the The frequency components of the first laser work together to cause a Stark energy level shift E1 on one of the sub-energy levels of the quantum bit basis vector; the / > The frequency component of the second laser is the same as that of the The frequency components of the two laser beams work together to cause the Stark energy level to shift E2 on another sub-energy level of the quantum bit basis vector, and E1 and E2 are not equal. The center frequency and power of the two laser beams are adjusted (dynamically) using the AOM, and the polarization of the two laser beams is adjusted using the wave plate. The two laser beams are irradiated from opposite directions to at least two quantum bits at the same time, and the irradiation time t is controlled by the AOM to realize a two-bit quantum logic gate.

In an exemplary embodiment, the embodiment of the present invention uses the MS method to construct a two-bit quantum logic gate; at this time, the EOM driving frequency is set to half of f _h ; the AOM driving frequency is set to: make the difference between the center frequencies of the two lasers and the eigenfrequency of the excited collective vibration mode less than 0.1 times the eigenfrequency. At this time, the two lasers can simultaneously excite the red and blue sideband transitions between the two quantum bit basis vectors, and the directions of the red and blue sideband transition wave vectors are opposite. Specifically, as shown in Figure 4, the center frequency of the first continuous laser in the embodiment of the present invention is f ₀ , and the EOM driving frequency is f _EOM ; the first continuous laser is phase modulated by the EOM to obtain a second continuous laser containing two frequency components; if the first continuous laser is a far-detuned laser, the second continuous laser must also be subjected to frequency screening by an etalon to suppress its even-order sideband components; the second continuous laser is split into a first laser and a second laser, and is driven by AOMs with driving frequencies of f _AOM1 and f _AOM2 , respectively. Then, the first laser contains two frequency components, which are The second laser contains two frequency components, namely/> f _AOM2 ±f _EOM . The difference in center frequency between the first laser and the second laser split out in the embodiment of the present invention |f _AOM1 -f _AOM2 | is close to ν, and its specific value can be calculated based on the relevant principles of quantum computing, for example, less than 0.1 times ν, and its specific value can be dynamically adjusted according to actual conditions. According to the specific properties of the quantum bit energy level structure, the polarization and power of the two second continuous lasers and the AOM driving frequency are set, so that the center frequency of the first laser is The frequency component of the second laser is the same as that of the The frequency components of the first laser work together to stimulate the red sideband transition between the two sub-energy levels contained in the quantum bit; the / > The frequency component of the second laser is the same as that of the The frequency components of the two lasers work together to stimulate the blue sideband transition between the two sub-energy levels contained in the quantum bit, and the wave vector directions of the red and blue sideband transitions are opposite. The center frequency and power of the two lasers are adjusted (dynamically) using the AOM, and the polarization of the two lasers is adjusted using the wave plate. The two lasers are irradiated to the quantum bit from opposite directions at the same time, and the irradiation time t is controlled by the AOM to realize a two-bit quantum logic gate.

It should be noted that the embodiments of the present invention do not limit the number of EOMs used. For example, the same EOM can be used to phase-modulate the first continuous laser to obtain a third continuous laser for constructing a single-bit quantum logic gate and a fourth continuous laser for constructing a dual-bit quantum logic gate; two EOMs can also be used to phase-modulate the first continuous laser to obtain a third continuous laser for constructing a single-bit quantum logic gate and a fourth continuous laser for constructing a dual-bit quantum logic gate; for example, the first continuous laser can be passed through two EOMs in sequence, and the first continuous laser can be modulated differently by different EOMs to obtain a third continuous laser for a single-bit quantum logic gate and a fourth continuous laser for a dual-bit quantum logic gate; or, the first continuous laser can be split into two paths, and each path passes through an EOM to obtain a third continuous laser for a single-bit quantum logic gate and a fourth continuous laser for a dual-bit quantum logic gate.

FIG5 is a block diagram of a device for constructing a quantum logic gate according to an embodiment of the present invention. As shown in FIG5 , the device comprises: a phase modulation unit and a construction unit; wherein:

The phase modulation unit is configured to: phase-modulate the first continuous laser through the EOM with a preset driving frequency to obtain a second continuous laser containing two frequency components for constructing a quantum logic gate;

The construction unit is configured to: construct a quantum logic gate by using the obtained second continuous laser;

Among them, quantum logic gates include: single-bit quantum logic gates and double-bit quantum logic gates.

The second continuous laser obtained by phase modulation in the embodiment of the present invention realizes single-bit quantum logic gates and double-bit quantum logic gates that are not affected by phase noise. The number of quantum logic gates is no longer limited by the laser coherence time, which provides a basis for realizing large-scale quantum computing.

In an exemplary embodiment, the first continuous laser in the embodiment of the present invention includes: a nearly detuned continuous laser;

Among them, the difference between the first center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the first excited state energy level is Δf; Δf is less than the first preset value times _fh ; _fh is the frequency difference between two sub-energy levels contained in the quantum bit basis vector; the first excited state energy level includes: the predetermined excited state energy level involved in the energy level transition for constructing a quantum logic gate.

In an exemplary embodiment, the first continuous laser in the embodiment of the present invention includes: a far-detuned continuous laser;

Among them, the difference between the second center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the second excited state energy level is Δf; Δf is greater than the second preset value times _fh ; _fh is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector; the second excited state energy level includes: the predetermined excited state energy level involved in the energy level transition for constructing a quantum logic gate.

In an exemplary embodiment, the device of the embodiment of the present invention further includes a filtering unit, which is configured as follows:

The second continuous laser light is passed through a preset etalon, so that the intensity of even-order sideband components in the second continuous laser light is lower than the intensity of odd-order sideband components.

In an exemplary embodiment, the difference between the frequencies of the two frequency components in the second continuous laser light in the embodiment of the present invention is equal to f _h ;

Among them, fh _is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector.

In an exemplary embodiment, when the quantum logic gate in the embodiment of the present invention is a single-bit quantum logic gate, the preset driving frequency f _EOM is equal to f _h /2;

Among them, fh _is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector.

In an exemplary embodiment, the construction unit of the embodiment of the present invention is configured as:

Adjusting the polarization, light intensity and center frequency of the second continuous laser of a single channel;

The second continuous laser after adjusting the polarization, light intensity and center frequency irradiates the quantum bit for a first preset time to achieve Raman transition between quantum bit basis vectors. In an exemplary embodiment, when the quantum logic gate in the embodiment of the present invention is a two-bit quantum logic gate, the preset driving frequency f _EOM is equal to f _h /2;

In an exemplary embodiment, the second continuous laser in the embodiment of the present invention includes: a laser that causes unequal Stark energy level shifts on two sub-energy levels included in the quantum bit basis vector.

In an exemplary embodiment, the construction unit of the embodiment of the present invention is configured as:

splitting the second continuous laser into two beams;

adjusting the polarization, center frequency and light intensity of the two second continuous laser beams obtained by splitting;

Two second continuous laser beams with adjusted polarization, center frequency and light intensity are simultaneously irradiated from different directions onto at least two quantum bits that need to construct a quantum logic gate;

Among them, the difference between the center frequencies of the two second continuous laser beams and the eigenfrequency of the collective vibration mode excited by the constructed two-bit quantum logic gate is less than the third preset value times the eigenfrequency.

“A person skilled in the art will appreciate that all or some of the steps, systems, and functional modules/units in the above disclosed methods may be implemented as software, firmware, hardware, or a suitable combination thereof. In hardware implementations, the division between the functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed by several physical components in cooperation. Some or all components may be implemented as software executed by a processor, such as a digital signal processor or a microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer-readable medium, which may include a computer storage medium (or a non-transitory medium) and a communication medium (or a transient medium). As is known in the art, As is well known to those skilled in the art, the term computer storage media includes volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technology, CD-ROM, digital versatile disks (DVD) or other optical disk storage, magnetic cassettes, magnetic tapes, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, as is well known to those of ordinary skill in the art, communication media typically contains computer readable instructions, data structures, program modules or other data in a modulated data signal such as a carrier wave or other transport mechanism, and may include any information delivery media".

Claims (12)

1. A method for constructing a quantum logic gate, comprising: Phase modulating the first continuous laser light by an electro-optic modulator (EOM) with a preset driving frequency to obtain a second continuous laser light containing two frequency components for constructing a quantum logic gate; Constructing a quantum logic gate using the obtained second continuous laser; The frequency difference between the two frequency components in the second continuous laser is equal to f _h , where f _h is the frequency difference between the two sub-energy levels included in the quantum bit basis vector; or, the second continuous laser includes lasers that cause unequal Stark energy level shifts on the two sub-energy levels included in the quantum bit basis vector; and the quantum logic gate includes: a single-bit quantum logic gate and a dual-bit quantum logic gate. 2. The method according to claim 1, characterized in that the first continuous laser comprises: a nearly detuned continuous laser; Among them, the difference between the first center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the first excited state energy level is Δf; Δf is less than the first preset value times _fh ; _fh is the frequency difference between two sub-energy levels contained in the quantum bit basis vector; the first excited state energy level includes: a predetermined excited state energy level involved in the energy level transition for constructing the quantum logic gate. 3. The method according to claim 1, characterized in that the first continuous laser comprises: a far-detuned continuous laser; Among them, the difference between the second center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the second excited state energy level is Δf; Δf is greater than the second preset value times _fh ; _fh is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector; the second excited state energy level includes: the predetermined excited state energy level involved in the energy level transition for constructing the quantum logic gate. 4. The method according to claim 3, characterized in that before constructing a quantum logic gate by using the obtained second continuous laser, the method further comprises: The second continuous laser light is passed through a preset etalon, so that the intensity of even-numbered sideband components in the second continuous laser light is lower than the intensity of odd-numbered sideband components. 5. The method according to claim 1, characterized in that the frequency difference between the two frequency components in the second continuous laser is equal to f _h , and when the quantum logic gate is a single-bit quantum logic gate, the preset driving frequency f _EOM is equal to f _h /2. 6. The method according to any one of claims 1 to 5, characterized in that the step of constructing a quantum logic gate using the obtained second continuous laser light comprises: Adjusting the polarization, light intensity and center frequency of the second continuous laser of a single channel; The second continuous laser after adjusting the polarization, light intensity and center frequency is irradiated on the quantum bit for a first preset time period to achieve Raman transition between quantum bit basis vectors. 7. The method according to claim 1, characterized in that the frequency difference between the two frequency components in the second continuous laser is equal to f _h , and when the quantum logic gate is a two-bit quantum logic gate, the preset driving frequency f _EOM is equal to f _h /2. 8. The method according to any one of claims 1, 2, 3, 4, or 7, characterized in that the step of constructing a quantum logic gate by using the obtained second continuous laser light comprises: Splitting the second continuous laser into two beams; Adjusting the polarization, center frequency and light intensity of the two split second continuous laser beams; The two second continuous laser beams with adjusted polarization, center frequency and light intensity are simultaneously irradiated from different directions onto at least two quantum bits that need to construct a quantum logic gate; The difference between the center frequencies of the two second continuous laser beams and the eigenfrequency of the collective vibration mode excited by the constructed two-bit quantum logic gate is less than a third preset value times the eigenfrequency. 9. A device for constructing a quantum logic gate, comprising: a phase modulation unit and a construction unit; wherein: The phase modulation unit is configured to: phase-modulate the first continuous laser through an electro-optic modulator EOM with a preset driving frequency to obtain a second continuous laser containing two frequency components for constructing a quantum logic gate; The construction unit is configured to: construct a quantum logic gate by using the obtained second continuous laser; The frequency difference between the two frequency components in the second continuous laser is equal to f _h , where f _h is the frequency difference between the two sub-energy levels included in the quantum bit basis vector; or, the second continuous laser includes lasers that cause unequal Stark energy level shifts on the two sub-energy levels included in the quantum bit basis vector; and the quantum logic gate includes: a single-bit quantum logic gate and a dual-bit quantum logic gate. 10. The device according to claim 9, characterized in that the first continuous laser comprises: a nearly detuned continuous laser; Among them, the difference between the first center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the first excited state energy level is Δf; Δf is less than the first preset value times _fh ; _fh is the frequency difference between two sub-energy levels contained in the quantum bit basis vector; the first excited state energy level includes: a predetermined excited state energy level involved in the energy level transition for constructing the quantum logic gate. 11. The device according to claim 9, characterized in that the first continuous laser comprises: a far-detuned continuous laser; Among them, the difference between the second center frequency of the first continuous laser and the resonant frequency of the quantum bit basis vector and the second excited state energy level is Δf; Δf is greater than the second preset value times _fh ; _fh is the frequency difference between the two sub-energy levels contained in the quantum bit basis vector; the second excited state energy level includes: the predetermined excited state energy level involved in the energy level transition for constructing the quantum logic gate. 12. The device according to claim 11, characterized in that the device further comprises a filtering unit configured to: The second continuous laser light is passed through a preset etalon, so that the intensity of even-numbered sideband components in the second continuous laser light is lower than the intensity of odd-numbered sideband components.