CN109510054B - Method for generating multi-frequency ultrashort laser pulse train - Google Patents
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Abstract
The invention discloses a method for generating a multi-frequency ultrashort laser pulse train, which forms a plurality of paths of ultrashort laser pulse trains respectively comprising a plurality of micropulses by independently beating a plurality of paths of chirped pulses respectively, wherein the micropulse repetition frequencies of each path of ultrashort laser pulse train are mutually independent and adjustable; and combining the multiple paths of ultrashort laser pulse trains to obtain the multiple-frequency ultrashort laser pulse train comprising multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses with adjustable repetition frequencies. The technical scheme provided by the invention effectively solves the problems in the prior art, and the generation method provided by the invention is simpler.
Description
Technical Field
The invention relates to the technical field of accelerators and free electron lasers, in particular to a method for generating a multi-frequency ultrashort laser pulse train.
Background
The terahertz wave band is an electromagnetic wave with the frequency of 0.1THz-10THz, and has a great significance for researching material science and material science due to the advantages and unique advantages of penetrability, low photon energy, high bandwidth, spectral fingerprint characteristics, ultrafast characteristics and the like.
THzpump/THz probe (TPTP) measurement by utilizing terahertz has unique identification capability on the dynamic collective behavior of particles with characteristic responses falling in a terahertz waveband, such as carrier dynamics, resonance of a magnetic vibrator, electronic transient loss and the like, so that the THzpump/THz probe has great importance on the research of characteristic physical properties of functional materials and the understanding of deep physical mechanisms. The basic mode of TPTP measurement is to utilize two beams of homologous terahertz light, wherein one beam is used for ultrafast excitation, and the other beam is used for ultrafast detection. Taking TPTP measurements as an example for the study of nonlinear THz field-induced carrier dynamics for condensed materials, THz pump light can excite doped semiconductor conduction band electrons, and homologous THz probe light is used to probe the characteristics of the field-induced carriers.
Most of the existing terahertz sources for TPTP measurement are single-frequency terahertz sources, namely the frequencies of pump light and probe light are consistent, and the adjustability is poor. However, if two independent terahertz sources are used to realize continuous adjustment of frequency, the requirement on synchronization of two beams of terahertz light is extremely high, which cannot be realized by the prior art. A dual-frequency terahertz source which can be used for TPTP measurement is in urgent need of development.
Because the main generation mechanism of terahertz includes two types, namely a wide-spectrum source generated by excitation of driving laser pulses and tunable single-frequency radiation based on Free Electron Laser (FEL), how to output a driving laser pulse train including multiple frequency sub-pulses becomes the key for developing a dual-frequency terahertz source suitable for TPTP measurement.
Disclosure of Invention
In view of this, the present invention provides a method for generating a multi-frequency ultrashort laser pulse train, which can obtain a multi-frequency ultrashort laser pulse train including a plurality of frequency-adjustable ultrashort laser pulse trains, and effectively solve the problems in the prior art.
In order to achieve the purpose, the technical scheme provided by the invention is as follows:
a method for generating a multi-frequency ultrashort laser pulse train comprises the following steps:
generating a plurality of paths of chirp pulses;
beating frequency of each chirp pulse to form multiple paths of ultrashort laser pulse strings respectively comprising a plurality of micropulses;
and combining the multiple paths of ultrashort laser pulse trains into a multi-frequency ultrashort laser pulse train.
Compared with the prior art, the technical scheme provided by the invention at least has the following advantages:
the invention provides a method for generating a multi-frequency ultrashort laser pulse train, which forms a plurality of paths of ultrashort laser pulse trains respectively comprising a plurality of micropulses by independently beating a plurality of paths of chirped pulses respectively, wherein the micropulse repetition frequencies of each path of ultrashort laser pulse train are mutually independent and adjustable; and combining the multiple paths of ultrashort laser pulse trains to obtain the multiple-frequency ultrashort laser pulse train comprising multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses with adjustable repetition frequencies.
When the beat frequency of each chirp pulse is the same as the independent beat frequency of each chirp pulse, the repetition frequency of the micro-pulses of the ultrashort laser pulse train is also the same, and the stacking effect of the ultrashort laser pulses can be realized by adjusting and optimizing the delay interval between the multiple chirp pulses, so that the ultrashort laser pulse train comprises more micro-pulses. Compared with the traditional stacking method of the ultrashort laser pulse train, the method for generating the ultrashort laser pulse train has simple steps, reduces the influence of dispersion effect and reduces the difficulty of dispersion compensation; compared with the traditional beat frequency method, the method for generating the ultrashort laser pulse train can obtain more micro-pulses while the broadening quantity is unchanged. The multi-frequency ultrashort laser pulse train generated by the technical scheme of the invention can excite the photocathode electron gun to obtain an ultrashort electron pulse train with higher electric charge and shorter beam group length, so that terahertz light with high coherent radiation power can be simply and efficiently generated.
When the beat frequencies of independent beats of each chirp pulse are different, the repetition frequencies of the micro pulses of the ultrashort laser pulse train are different, and the multifrequency ultrashort laser pulse train comprising a plurality of paths of ultrashort laser pulse trains respectively comprising the micro pulses with different repetition frequencies can be obtained, so that the photoconductive antenna can be excited to efficiently generate various high-power terahertz lights with different wave bands; the excited photocathode electron gun can generate electron pulse trains with various clustering frequencies, so that free electron laser radiation with various different wave bands can be further generated, and the obtained free electron laser also has independent adjustable characteristics; the method is applied to the TPTP measurement field, and can expand the measurement range for covering more measurement systems.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a flowchart of a method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present disclosure;
fig. 2 is a flowchart of another method for generating a multifrequency ultrashort laser pulse train according to an embodiment of the present disclosure;
FIG. 3 is a flowchart of a method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present disclosure;
FIG. 4 is a flowchart of a method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present disclosure;
fig. 5 is a schematic diagram of a multi-frequency ultrashort laser pulse train obtained under the condition that two beat frequencies are 0.5THz and 1.5THz, respectively, provided in this embodiment of the present application;
fig. 6 is a schematic diagram of a multi-frequency ultrashort laser pulse train obtained under the condition that two beat frequencies are 1.0THz and 1.5THz respectively according to the embodiment of the present application;
fig. 7 is a schematic diagram of a multi-frequency ultrashort laser pulse train obtained under the condition that two beat frequencies are both 1.5THz according to the embodiment of the present application;
FIG. 8 is a schematic diagram of an ultra-short laser pulse train obtained under the condition of a beat frequency of 1.5THz provided by the prior art;
fig. 9 is a schematic structural diagram of a device for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present disclosure;
fig. 10 is a schematic structural diagram of another apparatus for generating a multifrequency ultrashort laser pulse train according to an embodiment of the present disclosure.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As described in the background art, most of the existing terahertz sources for TPTP measurement are single-frequency terahertz sources, i.e., the frequencies of pump light and probe light are consistent, and the adjustability is poor, because the characteristic response frequency coverage range of a system to be measured may be very large, the single-frequency terahertz sources form great limitations on the application range of TPTP measurement. However, if two independent terahertz sources are used to realize continuous adjustment of frequency, the requirement on synchronization of two beams of terahertz light is extremely high, which cannot be realized by the prior art. A dual-frequency terahertz source which can be used for TPTP measurement is in urgent need of development.
Because the main generation mechanism of terahertz includes two types, namely a wide-spectrum source generated by excitation of driving laser pulses and tunable single-frequency radiation based on Free Electron Laser (FEL), how to output a driving laser pulse train including multiple frequency sub-pulses becomes the key for developing a dual-frequency terahertz source suitable for TPTP measurement.
Based on this, the embodiment of the present application provides a method and an apparatus for generating a multi-frequency ultrashort laser pulse train, which can obtain a multi-frequency ultrashort laser pulse train including a plurality of frequency-adjustable ultrashort laser pulse trains, and effectively solve the problems existing in the prior art, and the generation method provided by the embodiment of the present application is simpler. In order to achieve the above object, the technical solutions provided by the embodiments of the present application are described in detail below, specifically with reference to fig. 1 to 10.
Referring to fig. 1, a flowchart of a method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present application is shown, where the method for generating the multi-frequency ultrashort laser pulse train includes:
s1, generating multi-channel chirped pulses;
s2, performing beat frequency on each path of chirp pulse to form multiple paths of ultrashort laser pulse strings respectively comprising a plurality of micropulses;
and S3, combining the multiple paths of ultrashort laser pulse trains into multiple-frequency ultrashort laser pulse trains.
It can be understood that the ultra-short laser pulse train with quasi-sinusoidal modulation characteristic can be obtained by performing beat frequency on the chirped pulse, and the ultra-short laser pulse train comprises a plurality of micro-pulses; by analogy, each path of chirped pulse is independently beaten, and multiple paths of ultrashort laser pulse trains respectively comprising a plurality of micropulses can be obtained.
As can be seen from the above, multiple channels of ultrashort laser pulse trains respectively including multiple micropulses are formed by independently beating multiple channels of chirped pulses, and the micropulse repetition frequency of each channel of ultrashort laser pulse train is independently adjustable; and after the multiple paths of ultrashort laser pulse trains are combined, obtaining the multifrequency ultrashort laser pulse train which comprises multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses with adjustable repetition frequencies, namely the multifrequency ultrashort laser pulse train comprises multiple paths of ultrashort laser pulse trains, and each ultrashort laser pulse train comprises multiple micropulses with adjustable repetition frequencies.
When the beat frequency of each chirp pulse is the same as the independent beat frequency of each chirp pulse, the repetition frequency of the micro-pulses of the ultrashort laser pulse train is also the same, and the stacking effect of the ultrashort laser pulses can be realized by adjusting and optimizing the delay interval between the multiple chirp pulses, so that the ultrashort laser pulse train comprises more micro-pulses. Compared with the traditional stacking method of the ultrashort laser pulse train, the method for generating the ultrashort laser pulse train has the advantages that the steps are simple, the influence of a dispersion effect is reduced, and the difficulty of dispersion compensation is reduced; compared with the traditional beat frequency method, the method for generating the ultrashort laser pulse train in the embodiment of the application can obtain more micro-pulses while the broadening quantity is unchanged. The multi-frequency ultrashort laser pulse train generated by the technical scheme of the embodiment of the application can excite the photocathode electron gun to obtain an ultrashort electron pulse train with higher electric charge and shorter beam group length, so that terahertz light with high coherent radiation power can be simply and efficiently generated.
When the beat frequencies of independent beats of each chirp pulse are different, the repetition frequencies of the micro pulses of the ultrashort laser pulse train are different, and the multifrequency ultrashort laser pulse train comprising a plurality of paths of ultrashort laser pulse trains respectively comprising the micro pulses with different repetition frequencies can be obtained, so that the photoconductive antenna can be excited to efficiently generate various high-power terahertz lights with different wave bands; the excited photocathode electron gun can generate electron pulse trains with various clustering frequencies, so that free electron laser radiation with various different wave bands can be further generated, and the obtained free electron laser also has independent adjustable characteristics; the method is applied to the TPTP measurement field, and can expand the measurement range for covering more measurement systems.
In one embodiment, the multiple chirped pulses provided herein can be obtained by a single laser pulse process. Referring to fig. 2, a flowchart of another method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present application is shown, where S1, which is provided by the embodiment of the present application, generates multiple chirped pulses, and includes:
s101, outputting laser pulses by a laser source;
s102, performing chirp broadening on the laser pulse;
and S103, splitting the laser pulse subjected to chirp broadening at least once into multiple paths of chirp pulses.
It can be understood that, in the method for obtaining multiple chirped pulses provided in the embodiments of the present application, a single laser pulse may be output by one laser source, and then after chirping and stretching the laser pulse, the chirped and stretched laser pulse may be split at least once to obtain multiple chirped pulses. The laser pulse provided by the embodiment of the application is an ultrafast femtosecond pulse, the pulse width range of the ultrafast femtosecond pulse is not more than 150fs, and the pulse is a Fourier transform limit pulse. The laser source provided by the embodiment of the present application may be an oscillator type titanium sapphire laser, and the present application is not particularly limited thereto.
And when two paths of chirped pulses are needed, the chirped and broadened laser pulses can be subjected to primary beam splitting through one beam splitter to form two paths of chirped pulses. Or, when the chirp pulses with the number greater than two paths need to be generated, the laser pulses after chirp broadening can be subjected to beam splitting for multiple times, for example, two paths of sub-laser pulses are obtained by performing first beam splitting on the laser pulses through a beam splitter, then at least one path of sub-laser pulses obtained in the front is subjected to beam splitting into two paths of sub-laser pulses through the beam splitter again, and so on according to the rule, all the finally obtained sub-laser pulses are the multi-path chirp pulses.
In one embodiment, the multiple chirped pulses provided herein may be obtained by processing a plurality of laser pulses. Referring to fig. 3, a flowchart of a method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present application is shown, where S1, which is provided by the embodiment of the present application, generates multiple chirped pulses, and includes:
s111, outputting corresponding laser pulses by a plurality of laser sources;
and S112, performing chirp broadening on the laser pulse to obtain multiple paths of chirp pulses.
It can be understood that, in the method for obtaining multiple chirped pulses provided in the embodiments of the present application, laser pulses output by multiple laser sources respectively are first obtained, and then each laser pulse is chirped and broadened to form multiple chirped pulses. The laser pulse provided by the embodiment of the application is an ultrafast femtosecond pulse, the pulse width range of the ultrafast femtosecond pulse is not more than 150fs, and the pulse is a Fourier transform limit pulse. And, the laser source provided by the embodiment of the present application may be an oscillator type titanium sapphire laser, and the present application is not particularly limited.
It should be noted that, when the method provided in the embodiment of the present application includes a plurality of laser sources, at least one of the plurality of laser sources may be further subjected to chirp broadening and then split into beams, and the beams and the laser pulses that are subjected to chirp broadening and not split into beams form a plurality of chirp pulses, which is not limited in this application.
In an embodiment of the present application, the chirped stretching of the laser pulse provided by the present application includes:
and inputting the laser pulse into a parallel grating pair for chirp broadening.
Further, the inputting of the laser pulse into the parallel grating pair for chirp stretching provided by the embodiment of the present application includes:
inputting the laser pulse into the parallel grating pair for first chirp broadening;
and reflecting the laser pulse subjected to the first chirp broadening to the parallel grating pair for second chirp broadening.
It can be understood that, when the embodiments of the present application perform chirped stretching on a laser pulse, after performing first chirped stretching on the laser pulse, the laser pulse subjected to the first chirped stretching is reflected to a parallel grating pair to perform second chirped stretching, so as to increase a stretching amount. The chirped broadening provided by the embodiment of the present application is not limited to the parallel grating pair, and other structures may also be used to perform chirped broadening on the laser pulse.
Referring to fig. 4, a flowchart of a method for generating a multi-frequency ultrashort laser pulse train according to an embodiment of the present application is shown, where in S2, when performing beat frequency on each chirp pulse, the beat frequency is performed on any chirp pulse, and the method includes:
s21, when any one chirp pulse is subjected to beat frequency, splitting the chirp pulse into two sub-chirp pulses;
s22, reflecting the two paths of sub-chirped pulses with different optical paths respectively;
s23, beating the reflected two sub-chirped pulses to obtain one ultra-short laser pulse train comprising a plurality of micro-pulses, and forming multiple ultra-short laser pulse trains comprising a plurality of micro-pulses by the S21-S23.
In an embodiment of the present application, the splitting the chirped pulse into two sub-chirped pulses provided by the present application includes: and the chirp pulse is split into two paths of sub-chirp pulses by adopting a flat plate beam splitter, and the error of optical path difference can be reduced by adopting the flat plate beam splitter.
It can be understood that, in the process of performing beat frequency on any chirp pulse provided in the embodiment of the present application, by adjusting and optimizing the time interval of two sub-chirp pulses after splitting, the finally generated ultrashort laser pulse train can flexibly achieve the effect of stacking or non-stacking; and adjusting and optimizing the intensity of the two sub-chirped pulses (for example, adjusting the reflection-transmission ratio of the flat beam splitter) to adjust the power of the finally generated ultrashort laser pulse train. And the beat frequency can be changed by adjusting and optimizing the reflection optical path of the two sub-chirped pulses, and finally the width and the interval of the micro-pulse in the ultrashort laser pulse train are changed.
The technical scheme provided by the present application is compared with the prior art by combining the simulation result of the multi-frequency ultrashort laser pulse train shown in the attached drawing. Fig. 5 is a schematic diagram of a multi-frequency ultrashort laser pulse train obtained under the condition that two beat frequencies provided by the embodiment of the present application are 0.5THz and 1.5THz, fig. 6 is a schematic diagram of a multi-frequency ultrashort laser pulse train obtained under the condition that two beat frequencies provided by the embodiment of the present application are 1.0THz and 1.5THz, fig. 7 is a schematic diagram of a multi-frequency ultrashort laser pulse train obtained under the condition that two beat frequencies provided by the embodiment of the present application are 1.5THz, and fig. 8 is a schematic diagram of an ultrashort laser pulse train obtained under the condition that a beat frequency provided by the prior art is 1.5 THz. It should be noted that the multi-frequency ultrashort laser pulse trains shown in fig. 5 to 7 are based on two chirped pulses, and are respectively subjected to beat frequency and then combined (two beat frequencies are the respective corresponding beat frequencies of the independent beat frequencies of the two chirped pulses), so as to obtain data simulated under the condition of the multi-frequency ultrashort laser pulse train including two ultrashort laser pulse trains respectively including multiple micropulses.
In an exemplary diagram (simulation result) of the multi-frequency ultrashort laser pulse train shown in fig. 5 provided in this embodiment of the present application, two beat frequencies are 0.5THz (corresponding beat frequency optical path delay adjustment τ is 0.5ps) and 1.5THz (corresponding beat frequency optical path delay adjustment τ is 1.5ps), a splitting delay interval (i.e., a delay interval of two chirp pulses) in fig. 5(a) is adjusted to 12.5ps, and a splitting delay interval in fig. 5(b) is adjusted to 7ps, respectively.
In the schematic diagram (simulation result) of the multifrequency ultrashort laser pulse train shown in fig. 6 provided in the embodiment of the present application, two beat frequencies are 1.0THz (corresponding beat frequency optical path delay adjustment τ is 1.0ps) and 1.5THz (corresponding beat frequency optical path delay adjustment τ is 1.5ps), a splitting delay interval (delay interval of two chirp pulses) of fig. 6(a) is adjusted to 12.5ps, and a splitting delay interval of fig. 6(b) is adjusted to 8ps, respectively.
By the schematic diagrams of the multi-frequency ultrashort laser pulse train shown in fig. 5 and fig. 6, the multi-frequency ultrashort laser pulse train generated by the generation method provided by the embodiment of the present application may include two paths of ultrashort laser pulse trains with different frequencies, and by adjusting the beat frequency, the short frequency of the ultrashort laser pulse is also continuously adjustable and independent of each other, and the time interval of the ultrashort laser pulse train is also continuously adjustable.
In the schematic diagram (simulation result) of the multi-frequency ultrashort laser pulse train shown in fig. 7 provided in the embodiment of the present application, the beat frequencies of the two paths are the same and are both 1.5THz, and the splitting delay interval is adjusted to 4 ps.
FIG. 8 is a schematic diagram of an ultra-short laser pulse train obtained by the conventional beat frequency method under the condition that the beat frequency is 1.5THz,
as can be seen from the multifrequency ultrashort laser pulse train shown in fig. 7, when two paths of beat frequencies are controlled to be the same, the generated ultrashort laser pulse train has a stacking effect in cooperation with the adjustment of the light splitting delay interval, so that the total length of the pulse train can be equivalent to that in a pulse stacking scheme, and the pulse train is used as a driving laser to be beneficial to generating high-power THz light.
Comparing the data shown in fig. 7 with the data shown in fig. 8, it can be seen that, under the condition that the beat frequency is the same as 1.5THz, the ultrashort laser pulse train obtained by the existing beat frequency method only includes 16 micropulses, while the multifrequency ultrashort laser pulse train provided by the embodiment of the present application includes 22 micropulses, and the number of micropulses is increased by nearly 40%. Therefore, under the condition that the total charge quantity is kept unchanged, the charge quantity of a single micropulse in an electron pulse train generated by exciting a photocathode electron gun by the multi-frequency ultrashort laser pulse train obtained by the scheme provided by the embodiment of the application is reduced by more than 30%, so that the space charge repulsive force is effectively reduced to obtain a micropulse with a short length, the clustering factor of the electron pulse train is further improved, and the terahertz coherent radiation power is correspondingly and effectively improved.
Correspondingly, an embodiment of the present application further provides a device for generating a multi-frequency ultrashort laser pulse train, which is shown in fig. 9 and is a schematic structural diagram of the device for generating a multi-frequency ultrashort laser pulse train provided by the embodiment of the present application, wherein the device includes:
a chirp generation system 100, the chirp generation system 100 configured to generate a plurality of chirps;
a plurality of beat frequency systems 200, one beat frequency system 200 corresponding to one path of the chirped pulse, the beat frequency system 200 being configured to beat the chirped pulse into an ultrashort laser pulse train including a plurality of micropulses, so as to form a plurality of paths of ultrashort laser pulse trains including a plurality of micropulses respectively;
and a beam combining system 300, wherein the beam combining system 300 is configured to combine the multiple channels of ultrashort laser pulse trains into multiple frequency ultrashort laser pulse trains.
It can be understood that the ultra-short laser pulse train with quasi-sinusoidal modulation characteristic can be obtained by performing beat frequency on the chirped pulse through the beat frequency system, and the ultra-short laser pulse train comprises a plurality of micro-pulses; by analogy, each path of chirped pulse is independently beaten by the multiple beat frequency systems, so that multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses can be obtained.
As can be seen from the above, multiple channels of ultrashort laser pulse trains respectively including multiple micropulses are formed by independently beating multiple channels of chirped pulses, and the micropulse repetition frequency of each channel of ultrashort laser pulse train is independently adjustable; and after the multiple paths of ultrashort laser pulse trains are combined, obtaining the multifrequency ultrashort laser pulse train which comprises multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses with adjustable repetition frequencies, namely the multifrequency ultrashort laser pulse train comprises multiple paths of ultrashort laser pulse trains, and each ultrashort laser pulse train comprises multiple micropulses with adjustable repetition frequencies.
When the beat frequency of each chirp pulse is the same as the independent beat frequency of each chirp pulse, the repetition frequency of the micro-pulses of the ultrashort laser pulse train is also the same, and the stacking effect of the ultrashort laser pulses can be realized by adjusting and optimizing the delay interval between the multiple chirp pulses, so that the ultrashort laser pulse train comprises more micro-pulses. Compared with the traditional stacking method of the ultrashort laser pulse train, the method for generating the ultrashort laser pulse train has the advantages that the steps are simple, the influence of a dispersion effect is reduced, and the difficulty of dispersion compensation is reduced; compared with the traditional beat frequency method, the method for generating the ultrashort laser pulse train in the embodiment of the application can obtain more micro-pulses while the broadening quantity is unchanged. The multi-frequency ultrashort laser pulse train generated by the technical scheme of the embodiment of the application can excite the photocathode electron gun to obtain an ultrashort electron pulse train with higher electric charge and shorter beam group length, so that terahertz light with high coherent radiation power can be simply and efficiently generated.
When the beat frequencies of independent beats of each chirp pulse are different, the repetition frequencies of the micro pulses of the ultrashort laser pulse train are different, and the multifrequency ultrashort laser pulse train comprising a plurality of paths of ultrashort laser pulse trains respectively comprising the micro pulses with different repetition frequencies can be obtained, so that the photoconductive antenna can be excited to efficiently generate various high-power terahertz lights with different wave bands; the excited photocathode electron gun can generate electron pulse trains with various clustering frequencies, so that free electron laser radiation with various different wave bands can be further generated, and the obtained free electron laser also has independent adjustable characteristics; the method is applied to the TPTP measurement field, and can expand the measurement range for covering more measurement systems.
In one embodiment, the multiple chirped pulses provided herein can be obtained by a single laser pulse process. Referring to fig. 9, the chirp generation system 100 provided in the embodiment of the present application includes:
a laser source 110, wherein the laser source 110 is used for outputting laser pulses;
a chirped stretching unit 120, wherein the chirped stretching unit 120 is configured to perform chirped stretching on the laser pulse;
and a beam splitting unit 130, wherein the beam splitting unit 130 is configured to split the chirped and broadened laser pulse into multiple chirped pulses at least once.
It can be understood that, in the manner of obtaining multiple chirped pulses provided in the embodiments of the present application, a single laser pulse may be output by one laser source, and then the chirped pulse is chirped and stretched by the chirped stretching unit, and then the chirped and stretched laser pulse is split into multiple chirped pulses at least once. The laser pulse provided by the embodiment of the application is an ultrafast femtosecond pulse, the pulse width range of the ultrafast femtosecond pulse is not more than 150fs, and the pulse is a Fourier transform limit pulse. The laser source provided by the embodiment of the present application may be an oscillator type titanium sapphire laser, and the present application is not particularly limited thereto.
In an embodiment of the present application, the beam splitting unit provided by the present application includes: each stage of beam splitting module comprises at least one beam splitter, and on at least one path of beam splitting light path of at least one beam splitter of the ith stage of beam splitting module, a beam splitter of the (i + 1) th stage of beam splitting module is correspondingly arranged, wherein N is an integer larger than 0, and i is a positive integer not larger than N.
It can be understood that, when two chirped pulses are required in the application, the beam splitting unit may only include a first-stage beam splitting module, where the first-stage beam splitting module includes a beam splitter, and may split the chirped and broadened laser pulses into two chirped pulses by one beam splitter. Or, when the chirp pulses with the number greater than two paths need to be generated, the laser pulses subjected to chirp broadening can be split for multiple times, that is, the beam splitting unit can include a multistage beam splitting module, and each stage of beam splitting module can include at least one beam splitter, for example, the first stage of beam splitting module includes one beam splitter, and two paths of sub-laser pulses are obtained by first splitting the laser pulses through the beam splitter of the first stage of beam splitting module; the second-stage beam splitting module can comprise at least one beam splitter, at least one path of sub laser pulse split by the beam splitter of the first-stage beam splitting module is split into two paths of sub laser pulses again through the beam splitter of the second-stage beam splitting module, and by analogy with the rule, all the finally obtained sub laser pulses are the multi-path chirped pulses.
As shown in fig. 9, taking the application that two chirped pulses are required as an example, the beam splitting unit 130 includes a beam splitter 131, a reflection-transmission ratio of the beam splitter 131 may be 50% to 50%, and the beam splitter 131 splits the chirped and broadened laser pulses into two chirped pulses, wherein the intensities of the two chirped pulses may be adjusted by adjusting the reflection-transmission ratio of the beam splitter. In addition, the beam splitter provided by the embodiment of the application can be replaced by a combination of a half-wave plate and a polarization beam splitter, wherein the intensity of the two paths of chirped pulses can be adjusted by adjusting the angle of the half-wave plate
In one embodiment, the multiple chirped pulses provided herein may be obtained by processing a plurality of laser pulses. That is, the chirp generation system provided by the embodiment of the present application includes:
a plurality of laser sources for outputting laser pulses;
and the chirp stretching unit is used for performing chirp stretching on each laser pulse to obtain multiple paths of chirp pulses.
It can be understood that, in the manner of obtaining multiple chirped pulses provided in the embodiments of the present application, multiple laser pulses are obtained by multiple laser sources, and then each laser pulse is chirped and stretched to obtain multiple chirped pulses. The laser pulse provided by the embodiment of the application is an ultrafast femtosecond pulse, the pulse width range of the ultrafast femtosecond pulse is not more than 150fs, and the pulse is a Fourier transform limit pulse. And, the laser source provided by the embodiment of the present application may be an oscillator type titanium sapphire laser, and the present application is not particularly limited.
It should be noted that, when the method provided in the embodiment of the present application includes a plurality of laser sources, at least one of the plurality of laser sources may be further subjected to chirp broadening and then split into beams, and the beams and the laser pulses that are subjected to chirp broadening and not split into beams form a plurality of chirp pulses, which is not limited in this application.
In an embodiment of the present application, the chirped stretching unit provided in the present application employs a parallel grating to chirply stretch the laser pulse. As shown in fig. 9, the chirp stretching unit 120 provided in this embodiment of the present application includes at least one chirp stretching module (when the chirp pulse generation system includes one laser source, the chirp stretching unit includes one chirp stretching module; and when the chirp stretch generation system includes a plurality of laser sources, the chirp stretching unit includes a plurality of chirp stretching modules, and one chirp stretching module corresponds to one laser source), one chirp stretching module corresponds to one laser pulse, where the chirp stretching module includes:
a first reflection sub-module 121, where the first reflection sub-module 121 is configured to receive and output the laser pulse;
a parallel grating pair 122 disposed on the optical path of the first reflection sub-module 121, where the parallel grating pair 122 is configured to perform a first chirp broadening on the laser pulse output by the first reflection sub-module 121;
and a second reflection sub-module 123 disposed on the optical path of the parallel grating pair 122, where the second reflection sub-module 123 is configured to reflect the laser pulse subjected to the first chirp broadening to the parallel grating pair 122, the parallel grating pair 122 performs second chirp broadening on the laser pulse subjected to the first chirp broadening, and outputs the laser pulse to the first reflection sub-module 121, and the first reflection sub-module 121 outputs the laser pulse subjected to the second chirp broadening (when the chirp pulse generation system includes one laser source, the laser pulse is output to the beam splitting unit; and when the chirp pulse generation system includes multiple laser sources, the output pulse is a chirp pulse).
It can be understood that, when the embodiments of the present application perform chirped stretching on a laser pulse, after performing first chirped stretching on the laser pulse, the laser pulse subjected to the first chirped stretching is reflected to a parallel grating pair to perform second chirped stretching, so as to increase a stretching amount. The chirped broadening provided by the embodiment of the present application is not limited to the parallel grating pair, and other structures may also be used to perform chirped broadening on the laser pulse.
Optionally, the chirp broadening provided by the embodiment of the present application adopts a parallel grating pair, where the parallel grating pair is composed of two gratings that are oppositely disposed and parallel to each other, and the grating provided by the embodiment of the present application may be a holographic diffraction grating, so as to generate the second laser pulse with a linear chirp characteristic (an instantaneous frequency of an optical field changes as a linear function of time) by using group delay dispersion thereof. In addition, the embodiments of the present application may also be replaced with optical elements having similar characteristics, such as Gires-Tournois interference mirrors or prisms.
As shown in fig. 9, the first sub-module 121 provided in this embodiment of the present application may be a prism beam splitter (the prism beam splitter may be a half mirror with T: R being 50%: 50%, or a half mirror with full transmission toward the laser source side and full reflection on the other side). The second reflection sub-module 123 provided in this embodiment of the present application may be a retro-reflection prism, configured to change a transmission direction of the second laser pulse output by the parallel grating pair 122 and subjected to the first chirp broadening, so as to return the second laser pulse to the parallel grating pair 122 for the second chirp broadening, so as to increase the broadening amount.
In addition, the first reflection submodule provided by the embodiment of the present application may also be a flat plate beam splitter. And the second reflection sub-module can also be composed of plane reflectors, the second reflection sub-module can comprise two plane reflectors which are arranged in a mutually perpendicular mode, and the mirror surface direction and the normal direction of any plane reflector form an included angle of 45 degrees with the direction of the laser pulse which is incident to the plane reflector.
As shown in fig. 9, the beat frequency system 200 provided in the embodiment of the present application includes:
the beam splitting interference unit 210, where the beam splitting interference unit 210 is configured to split the chirped pulse into two sub-chirped pulses;
the two reflectors 220 are respectively disposed on the two optical paths of the beam splitting interference unit 210, a mirror surface of each reflector 220 is perpendicular to a direction of the corresponding sub-chirped pulse, and the two reflectors 220 are used for respectively reflecting the two sub-chirped pulses with different optical lengths, so that the reflected two sub-chirped pulses generate beat frequencies.
In an embodiment of the present application, the splitting the chirped pulse into two sub-chirped pulses provided by the present application includes: and the chirp pulse is split into two paths of sub-chirp pulses by adopting a flat plate beam splitter, and the error of optical path difference can be reduced by adopting the flat plate beam splitter.
It can be understood that, in the process of performing beat frequency on a corresponding chirp pulse by the beat frequency system provided by the embodiment of the present application, the time interval of two sub-chirp pulses after beam splitting is adjusted and optimized, so that the finally generated ultrashort laser pulse train can flexibly achieve the effect of stacking or not stacking; and adjusting and optimizing the intensity of the two sub-chirped pulses (for example, adjusting the reflection-transmission ratio of the flat beam splitter) to adjust the power of the finally generated ultrashort laser pulse train. And the beat frequency can be changed by adjusting and optimizing the reflection optical path of the two sub-chirped pulses, and finally the width and the interval of the micro-pulse in the ultrashort laser pulse train are changed.
As shown in fig. 9, when the chirped pulse generation system 100 includes the beam splitting unit 130, the chirped pulse output by the beam splitting unit 130 may be directly incident on the beam splitting interference unit 210 by optimizing the position relationship between the beam splitting unit 130 and the beam splitting interference unit 210, so as to save the arrangement of other optical path guiding structures.
In addition, when the chirped pulse generation system provided in the embodiment of the present application includes a beam splitting unit, the position relationship between the beam splitting unit and the beam splitting interference unit may not be limited, and then the chirped pulse output by the beam splitting unit is guided to be incident on the beam splitting interference unit through another optical path guiding structure, as shown in fig. 10, a schematic structural diagram of another apparatus for generating a multi-frequency ultrashort laser pulse string provided in the embodiment of the present application is shown, where when the chirped pulse generation system includes the beam splitting unit, the apparatus may further include an optical path guiding structure, the optical path guiding structure provided in the embodiment of the present application may include two mirrors 410, and the two mirrors 410 complete guiding and incident of one chirped pulse output by the beam splitting mirror 131 into the beam splitting interference unit 210.
Optionally, an included angle between the mirror surface direction of the mirror 410 and the transmission direction of the pulse incident to the mirror 410 is 45 degrees. The reflecting mirror is used for flexibly changing the transmission direction of the light path, and in practical application, the included angle between the mirror surface direction of the reflecting mirror and the incident pulse transmission direction can be adjusted at will within the range of (0 degrees and 90 degrees), so that the application is not particularly limited.
In an embodiment of the present application, the beam combining system provided by the present application includes:
the beam combining unit comprises a first stage beam combining unit and an Mth stage beam combining unit, each stage beam combining unit comprises at least one beam combining mirror, at least one path of incident light of at least one beam combining mirror of the j + 1th stage beam combining unit is correspondingly provided with one beam combining mirror of the jth stage beam combining unit, M is an integer larger than 0, and j is a positive integer not larger than M.
It can be understood that, when combining the multiple paths of ultrashort laser pulse trains, firstly grouping the multiple paths of ultrashort laser pulse trains two by two, wherein the first-stage beam combining unit comprises a plurality of beam combining mirrors, each beam combining mirror corresponds to one group, and each group is combined through the beam combining mirrors, and if the number of the ultrashort laser pulse trains is odd, one grouped ultrashort laser pulse train is remained to be combined in the second-stage beam combining unit; and grouping the ultra-short laser pulse trains after the first-stage beam combination again in pairs, and then combining the corresponding groups through a beam combining mirror in the second-stage beam combination unit, wherein if the number of the ultra-short laser pulse trains is odd, the rest ultra-short laser pulse trains after the grouping are combined in the third-stage beam combination unit, so as to analogize the rule, and all the ultra-short laser pulse trains are combined into multi-frequency ultra-short laser pulse trains.
In an embodiment of the present application, included angles between the transmission direction of the pulse incident to the beam combiner and normal lines of the medium surface and the medium surface of the beam combiner are both 45 °, so as to ensure that the transmission directions of the two beams of pulses after passing through the beam combiner are on the same straight line. Wherein, the beam combining mirror can be replaced by a polarization beam combining mirror.
As shown in fig. 9, taking two ultrashort laser pulse trains as an example for explanation, the beam combining system 300 includes a first-stage beam combining unit, and the beam combining unit includes a beam combining mirror 310, and the beam combining mirror 310 combines the two ultrashort laser pulse trains output by the two beat frequency systems 200 into a multi-frequency ultrashort laser pulse train.
The embodiment of the application provides a method and a device for generating a multi-frequency ultrashort laser pulse train, wherein multiple paths of chirped pulses are independently beaten to form multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses, and the micropulse repetition frequencies of the ultrashort laser pulse trains are independent and adjustable; and combining the multiple paths of ultrashort laser pulse trains to obtain the multiple-frequency ultrashort laser pulse train comprising multiple paths of ultrashort laser pulse trains respectively comprising multiple micropulses with adjustable repetition frequencies.
When the beat frequency of each chirp pulse is the same as the independent beat frequency of each chirp pulse, the repetition frequency of the micro-pulses of the ultrashort laser pulse train is also the same, and the stacking effect of the ultrashort laser pulses can be realized by adjusting and optimizing the delay interval between the multiple chirp pulses, so that the ultrashort laser pulse train comprises more micro-pulses. Compared with the traditional stacking method of the ultrashort laser pulse train, the method for generating the ultrashort laser pulse train has the advantages that the steps are simple, the influence of a dispersion effect is reduced, and the difficulty of dispersion compensation is reduced; compared with the traditional beat frequency method, the method for generating the ultrashort laser pulse train in the embodiment of the application can obtain more micro-pulses while the broadening quantity is unchanged. The multi-frequency ultrashort laser pulse train generated by the technical scheme of the embodiment of the application can excite the photocathode electron gun to obtain an ultrashort electron pulse train with higher electric charge and shorter beam group length, so that terahertz light with high coherent radiation power can be simply and efficiently generated.
When the beat frequencies of independent beats of each chirp pulse are different, the repetition frequencies of the micro pulses of the ultrashort laser pulse train are different, and the multifrequency ultrashort laser pulse train comprising a plurality of paths of ultrashort laser pulse trains respectively comprising the micro pulses with different repetition frequencies can be obtained, so that the photoconductive antenna can be excited to efficiently generate various high-power terahertz lights with different wave bands; the excited photocathode electron gun can generate electron pulse trains with various clustering frequencies, so that free electron laser radiation with various different wave bands can be further generated, and the obtained free electron laser also has independent adjustable characteristics; the method is applied to the TPTP measurement field, and can expand the measurement range for covering more measurement systems.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. A method for generating a multi-frequency ultrashort laser pulse train, comprising:
generating a plurality of paths of chirp pulses;
beating frequency of each chirp pulse to form multiple paths of ultrashort laser pulse strings respectively comprising a plurality of micropulses;
and combining the multiple paths of ultrashort laser pulse trains into a multi-frequency ultrashort laser pulse train.
2. The method of generating multi-frequency ultrashort laser pulse train of claim 1, wherein generating the multi-channel chirped pulses comprises:
outputting laser pulses by a laser source;
performing chirp broadening on the laser pulse;
and splitting the laser pulse subjected to chirp broadening at least once into multiple chirp pulses.
3. The method of generating multi-frequency ultrashort laser pulse train of claim 1, wherein generating the multi-channel chirped pulses comprises:
outputting respective laser pulses by a plurality of laser sources;
and performing chirp broadening on the laser pulse to obtain multiple paths of chirp pulses.
4. The method of generating the multifrequency ultrashort laser pulse train of claim 2 or 3, wherein chirping the laser pulses for broadening comprises:
and inputting the laser pulse into a parallel grating pair for chirp broadening.
5. The method of generating the multifrequency ultrashort laser pulse train of claim 4, wherein inputting the laser pulses into a parallel grating pair for chirped stretching comprises:
inputting the laser pulse into the parallel grating pair for first chirp broadening;
and reflecting the laser pulse subjected to the first chirp broadening to the parallel grating pair for second chirp broadening.
6. The method of claim 1, wherein the beating the one chirp pulse comprises:
splitting the chirped pulse into two paths of sub-chirped pulses;
reflecting the two paths of sub-chirped pulses with different optical paths respectively;
and beating the reflected two paths of sub-chirped pulses.
7. The method for generating the multifrequency ultrashort laser pulse train according to claim 6, wherein splitting the chirped pulse into two sub-chirped pulses comprises:
and splitting the chirped pulse into two paths of sub-chirped pulses by adopting a flat plate beam splitter.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1266298A (en) * | 2000-03-30 | 2000-09-13 | 中国科学院上海光学精密机械研究所 | Multi-light pulse generator for femtosecond terawatt-level laser device |
| CN102255225A (en) * | 2011-05-20 | 2011-11-23 | 上海理工大学 | Independent chirp parameter regulating system for realizing two-tone laser field |
| CN103840366A (en) * | 2014-03-07 | 2014-06-04 | 上海理工大学 | Method for achieving terahertz wave center frequency continuous adjustability through pulse laser widening |
| JP2014149470A (en) * | 2013-02-04 | 2014-08-21 | Waseda Univ | Chirp control method and chirp control apparatus |
| CN105226498A (en) * | 2015-11-07 | 2016-01-06 | 山东大学 | A kind of dual laser based on two stimulated Raman scattering medium |
| CN105470786A (en) * | 2016-01-25 | 2016-04-06 | 中国科学技术大学 | Tunable terahertz source based on electronic cloud string and over-mode waveguide coupling mechanism |
| CN106058618A (en) * | 2016-05-24 | 2016-10-26 | 中国科学技术大学 | Terahertz radiation source based on multi-mode simultaneous coherent excitation |
| CN107910736A (en) * | 2017-12-19 | 2018-04-13 | 成都师范学院 | Increase the chirped laser pulse frequency spectrum shaping system of Dare interferometer based on Mach |
-
2018
- 2018-12-27 CN CN201811609790.8A patent/CN109510054B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1266298A (en) * | 2000-03-30 | 2000-09-13 | 中国科学院上海光学精密机械研究所 | Multi-light pulse generator for femtosecond terawatt-level laser device |
| CN102255225A (en) * | 2011-05-20 | 2011-11-23 | 上海理工大学 | Independent chirp parameter regulating system for realizing two-tone laser field |
| JP2014149470A (en) * | 2013-02-04 | 2014-08-21 | Waseda Univ | Chirp control method and chirp control apparatus |
| CN103840366A (en) * | 2014-03-07 | 2014-06-04 | 上海理工大学 | Method for achieving terahertz wave center frequency continuous adjustability through pulse laser widening |
| CN105226498A (en) * | 2015-11-07 | 2016-01-06 | 山东大学 | A kind of dual laser based on two stimulated Raman scattering medium |
| CN105470786A (en) * | 2016-01-25 | 2016-04-06 | 中国科学技术大学 | Tunable terahertz source based on electronic cloud string and over-mode waveguide coupling mechanism |
| CN106058618A (en) * | 2016-05-24 | 2016-10-26 | 中国科学技术大学 | Terahertz radiation source based on multi-mode simultaneous coherent excitation |
| CN107910736A (en) * | 2017-12-19 | 2018-04-13 | 成都师范学院 | Increase the chirped laser pulse frequency spectrum shaping system of Dare interferometer based on Mach |
Non-Patent Citations (1)
| Title |
|---|
| The chirp-control of frequency-tunable narrowband terahertz pulses by nonlinearly chirped laser pulse beating;Shohei Kamada et al.;《APPLIED PHYSICS LETTERS》;20140310;第104卷(第10期);第101102-1到101102-5页 * |
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