92 results about "Nonlinear crystals" patented technology

The invention discloses a non-linear frequency conversion regenerative amplification device and a method thereof, and belongs to the technical field of laser non-linear frequency conversion. The device comprises a signal light injection unit, a regeneration amplification cavity unit and a pump light synchronization unit. The regenerative amplification cavity unit comprises an optical resonant cavity structure module, a polarization control module and a nonlinear action module. A time domain switch is formed through the polarization control module under the driving of the time schedule controller, and the preset number of times of circulation of signal light in the cavity is accurately controlled. And meanwhile, the pump light synchronization unit generates pump pulse string laser which is synchronous with the circulation process and has sub-pulse power increasing in sequence, so that the signal light and one corresponding pump sub-pulse are subjected to optical parametric amplification in the nonlinear crystal in each circulation. The space complexity of multi-stage amplification is converted into time domain controllability, high-efficiency and high-gain nonlinear frequency conversion is realized by using a single-stage compact structure, and the integration level and the stability of the system are remarkably improved.

This application discloses an optical parametric oscillator and a laser generating device, relating to the field of laser technology. The optical parametric oscillator includes a first optical fiber, a mirror assembly, a nonlinear crystal, and a second optical fiber. The first optical fiber has a first receiving end and a first output end. The first receiving end is used to receive pump light. The second optical fiber has a second receiving end and a second output end. Light output from the first output end can be transmitted to the second receiving end via the mirror assembly and the nonlinear crystal. The second output end is used to output signal light. The mirror assembly includes multiple mirrors. The nonlinear crystal is located in the optical path between two mirrors. A first grating is disposed on the first optical fiber, and a second grating is disposed on the second optical fiber. Both the first and second gratings are fiber Bragg gratings. Because this application uses a first optical fiber and a second optical fiber to define the light transmission path, compared to a free-space optical path, the optical fiber can be coiled, which is beneficial for reducing the overall size and improving integration.

This application provides a semiconductor laser and a terahertz source for generating terahertz waves. The semiconductor laser includes: a substrate; a mesa located on the substrate; and a ridge waveguide and lateral coupling gratings located on the mesa, with the lateral coupling gratings located on both sides of the ridge waveguide. The lateral coupling gratings are configured such that the frequency difference between the fundamental transverse mode wavelength and the second-order transverse mode wavelength of the lasing light emitted by the semiconductor laser is 0.1 THz–10 THz. The semiconductor laser of this application, through the optimized configuration of the ridge waveguide and the lateral coupling gratings on both sides, precisely achieves simultaneous output of the fundamental and second-order transverse modes with a frequency difference on the order of terahertz. Combined with a polarization controller and a nonlinear crystal, it can stably output terahertz waves in the target frequency band. Compared with traditional solutions, the semiconductor laser of this application can simultaneously output the fundamental and second-order transverse modes with a frequency difference on the order of terahertz, offering advantages in miniaturization and low cost.

The application discloses a high-energy and few-cycle blue light laser generation method and device, and belongs to the technical field of ultrafast laser, wherein the method comprises the following steps: adopting a nonlinear crystal to double frequency of a base frequency pulse after compression, and performing at least twice pulse width compression on the obtained double frequency pulse to obtain high-energy and few-cycle blue light laser; wherein, the double frequency process and the pulse width compression process are both performed in a cavity filled with helium; the pulse width compression process is performed through spectral broadening of a solid sheet; since the helium has extremely low linear dispersion and nonlinear coefficient and extremely high ionization energy, not only the solid sheet damage can be avoided, and a part of spectral broadening is contributed, but also an environment close to vacuum can be provided in terms of dispersion and laser-induced ionization, so that the dispersion compensation of the double frequency pulse is easier, and the energy loss caused by gas ionization and the input energy limitation are avoided, and higher output energy is allowed; the problem that the high-energy and ultra-short pulse width blue light pulse is difficult to be realized simultaneously at present is effectively solved.

The application relates to the field of laser technology, in particular to a device and a method for generating wide-tuning narrow-line-width mid-infrared laser, wherein the pump light emitted by a nanosecond pulse OPO base frequency pump source is reflected to a beam splitter by a full reflection mirror after passing through a first adjuster; the pump light emitted by a continuous wave OPO base frequency pump source is irradiated to the beam splitter after passing through a second adjuster; the two beams of pump light are combined after passing through the beam splitter, are focused after passing through a plano-convex lens, are irradiated to a first plano-concave full reflection mirror, and then are transmitted to a nonlinear crystal to generate signal light and idler mid-infrared laser through nonlinear frequency conversion; the idler mid-infrared laser and the residual pump light are transmitted to a doublet mirror and are separated by the doublet mirror; the signal light is reflected to the nonlinear crystal in sequence through a second plano-concave full reflection mirror, a first plane full reflection mirror, a second plane full reflection mirror and the first plano-concave full reflection mirror, and an oscillation closed loop is formed. The application realizes that the pulse OPO outputs a pulse with a line width less than 90 MHz in the tuning range, and the extraction efficiency of the idler light is as high as 9.3%.

The application relates to the technical field of solid laser emitters, in particular to a device for the thermal management of a nonlinear crystal in a laser. The device comprises a base, a fixing member, a pressing member and a pressing device, the pressing member is located between the base and the vertical plate part, a through V-shaped groove is formed on the side of the pressing member facing the base, the V-shaped groove and the mounting plate of the electric push rod arranged on the base and perpendicular to each other form a containing cavity for containing the nonlinear crystal, the mounting surface of the mounting plate and the V-shaped surface of the V-shaped groove are both provided with a temperature control assembly for adjusting the temperature of the nonlinear crystal, the temperature control assembly comprises a heating plate and a heat dissipation plate; and the pressing device is used for pressing the nonlinear crystal. The device can quickly adjust the temperature of the nonlinear crystal material, realizes the efficient thermal management of the amorphous material, and improves the stability of the nonlinear crystal material.

This invention provides a device and method for generating simultaneously emitted three wavelengths of laser light with equal spacing, relating to the field of laser technology. The device includes a pump source, a half-wave plate, an optical isolator, a focusing lens, an input mirror, a Raman crystal, an output mirror, a nonlinear crystal, and a dichroic mirror arranged sequentially along the optical path. The pump light, after its polarization direction is adjusted by the half-wave plate and the optical isolator, is focused onto the Raman crystal. Stimulated Raman scattering generates first and second Stokes beams, which are then converted to sum-frequency light by the sum-frequency effect of the nonlinear crystal. Finally, the dichroic mirror outputs three equally spaced wavelengths of laser light. This invention separates the Raman conversion and sum-frequency processes through an external cavity structure, achieving for the first time the simultaneous emission of three equally spaced wavelengths of laser light, offering advantages such as high output energy, equal wavelength spacing, and simultaneous emission of three wavelengths.

A principle which enables the generation of macroscopic Fock and sub-Poissonian states is disclosed. Generic components of the system include: an electromagnetic structure (possessing one or more electromagnetic resonances), a nonlinear electromagnetic element (such as a nonlinear crystal near or inside the structure), and a source of light. In one embodiment, stimulated gain is used to create large numbers of photons in a cavity, but with very low photon number noise (uncertainty) in the cavity, and thus acts as a Fock laser. This Fock laser is capable of producing these states due to a very sharp intensity-dependent gain (or loss) that selects a particular photon number. The disclosed system and method are robust against both atomic and optical decoherence. Various examples of the new Fock laser design are also described.

The invention provides a combined rotating frequency doubling crystal point changing device, a point changing method and a laser. The combined rotating frequency doubling crystal point changing device comprises a refraction lens, a folded cavity mirror, a nonlinear crystal and an end mirror. The refraction lens is rotatably arranged, and fundamental frequency light enters the folding cavity mirror through the refraction lens and is reflected to the nonlinear crystal through the folding cavity mirror; the end mirror reflects fundamental frequency light entering the nonlinear crystal and frequency doubling light generated after the fundamental frequency light enters the nonlinear crystal, and the frequency doubling light is output through the output end of the nonlinear crystal. When the output point of the nonlinear crystal needs to be changed, the refraction lens is rotated by a certain angle, so that the light path of the fundamental frequency light refracted by the refraction lens is changed, and the incidence point of the fundamental frequency light and the output point of the frequency doubling light of the nonlinear crystal are further changed. The operation is greatly saved, and the implementation method is simple and rapid.

The invention discloses an inter-satellite high-precision ranging system and method based on a balanced timing detection technology, and relates to the technical field of space precision measurement and time frequency transmission. The system comprises a first satellite terminal and a second satellite terminal which are connected through a bidirectional free space laser link. Each terminal is equipped with a clock optical frequency comb as a time reference and a time programming optical frequency comb as a local tracking oscillator. According to the invention, the full-digital sequential control capability of the TPFC is utilized, the pulse phase is dynamically regulated and controlled through the FPGA, and rapid scanning and real-time locking tracking of an inter-satellite high-speed moving target are realized; meanwhile, in combination with a balance optical cross-correlation (BOC) technology based on a nonlinear crystal, background noise is eliminated by utilizing differential detection, and high-sensitivity femtosecond-level time synchronous detection close to quantum limit is realized. The system has the characteristics of compact structure, high dynamic adaptability, excellent anti-noise performance and the like.

The utility model relates to a wavelength switching output device for a laser. The wavelength switching output device comprises a mounting seat, a driving part, a first transmission part, a second transmission part, a first nonlinear crystal assembly and a second nonlinear crystal assembly, the first nonlinear crystal assembly and the second nonlinear crystal assembly are movably mounted on the mounting seat respectively, and the first nonlinear crystal assembly and the second nonlinear crystal assembly coincide or do not coincide in the light propagation direction in the moving process; the first nonlinear crystal component and / or the second nonlinear crystal component can pass through the first nonlinear crystal component and / or the second nonlinear crystal component; and the driving piece is used for driving the first nonlinear crystal assembly to move through the first transmission piece, and is used for driving the second nonlinear crystal assembly to move through the second transmission piece. According to the utility model, lasers with different wavelengths can be output; and in addition, the switching convenience and accuracy are improved and the switching efficiency is improved in a mode that the driving part is used for driving switching.

An optical parametric multi-pass apparatus for generating laser radiation through optical parametric amplification or generation converts pump radiation into signal and idler radiation. It includes a multi-pass device with multiple mirror elements arranged to provide several beam paths from an input section to an output section of the device. The input section receives pump radiation, and the output section delivers signal radiation as the generated laser output. At least one optically nonlinear crystal is positioned within the device to enable the parametric process using the pump radiation. The mirror configuration ensures multiple passes of the beam paths through the crystal. The device is further designed to filter along the beam paths so that idler radiation is suppressed after at least one pass. A corresponding laser apparatus and method for generating laser radiation are also described.

The invention belongs to the technical field of photon detection, and particularly relates to a frequency up-conversion THz wave-based multi-photon detection system and method, and the system comprises a pump light source unit, a beam combiner, a nonlinear crystal, a light splitting unit, a space photon counting detector, a light shaping device, and a controller. According to the technology, THz up-conversion signals are converted from single time domain detection to time and space domain coincidence detection, meanwhile, by means of the spatial resolving power of the multi-photon detector, when time-synchronous fluorescence is achieved, the technology can be combined with the space light gate technology to execute detection in a light gate where the signals are expected to arrive, and therefore fluorescence components are restrained. Finally, effective detection of THz up-conversion signals with spontaneous parametric up-conversion fluorescence can be realized.

A narrow linewidth mid infrared laser, including a pumping laser diode with a fast-axis compressor and a pumping wavelength λo; and an optical resonator arranged to receive the pumping wavelength λo, the optical resonator including a laser crystal with a lasing wavelength λp, a dichroic mirror, and a nonlinear crystal to generate an idler wavelength λi.

The invention discloses an ultra-short pulse optical parametric oscillator based on a bicrystal structure, and relates to a laser and an assembly, and the oscillator comprises a first beam shaper (2) which is used for shaping idler frequency light (1); a second beam shaper (4) for shaping the pump light (3); a dichroscope (5); the first nonlinear crystal (6) is arranged on a light emitting path of the dichroscope (5), and the first nonlinear crystal (6) is used as an input coupling mirror of the optical parametric oscillator; the second nonlinear crystal (7) is arranged on a light emitting path of the first nonlinear crystal (6), and the first nonlinear crystal (6) and the second nonlinear crystal (7) form a resonant cavity; and the three-direction color mirror (9) is arranged on a light emitting path of the second nonlinear crystal (7) and is used for separating the pump light, the signal light (8) generated by nonlinear frequency conversion and the amplified idle frequency light (1) and transmitting and outputting the idle frequency light. The conversion efficiency of the optical parameter amplification process is improved, and the overall amplification performance of the optical parameter amplifier is guaranteed.

The application discloses a kind of high stability optical parametric oscillator assisted by intelligent feedback algorithm, and relates to the technical field of optical parametric oscillator.The oscillator includes 515 nm pump laser source, half-wave plate, polarization beam splitter, plane mirror, dichroic mirror, concave focusing cavity mirror, nonlinear crystal, output coupling mirror, four-quadrant photodetector based on STM32, DAC high-voltage drive board and piezoelectric deflection mirror.The application utilizes four-quadrant photodetector to monitor laser output power in real time, and collects data through the combination of ADC and direct memory access (DMA), realizes double buffering operation by means of full transmission and half transmission mechanism, to efficiently obtain the performance indicators required by SPGD algorithm.The algorithm continuously iterates and optimizes, controls piezoelectric deflection mirror in real time, precisely adjusts cavity length and beam pointing, and effectively stabilizes laser output power.

The application discloses a kind of ultrafast pulse laser autocorrelation measurement system and method, comprising: beam splitting unit;Reference light path;Delay light path;Adjustable delay unit;Delay light mirror group;Reference light mirror group;Combining unit;Focusing unit;Asymmetric air nanoslit photodetector, for receiving the light beam output by combining unit and focusing unit, and output corresponding photocurrent signal;Signal acquisition and processing unit, for acquiring photocurrent signal, and obtaining the intensity autocorrelation curve of ultrafast pulse laser according to the time delay change relationship of photocurrent signal, and inversion obtains the pulse width information of ultrafast pulse laser.The application utilizes asymmetric air nanoslit photodetector to directly output photocurrent signal, realizes the autocorrelation measurement of ultrafast pulse laser, without nonlinear crystal, compact structure, easy to integrate, suitable for measuring femtosecond or picosecond ultrafast pulse laser.

This technology provides a way to directly observe terahertz waves generated inside a nonlinear crystal in a terahertz wave parametric generator. [Solution] The terahertz wave observation device 101 comprises a terahertz wave generating nonlinear crystal 1 that generates terahertz waves 3 from excitation light 2 by optical parametric generation, an excitation light source 21 that incidents excitation light 2 onto the terahertz wave generating nonlinear crystal 1, a probe light source 22 that incidents probe light 5 onto the terahertz wave generating nonlinear crystal 1, a first prism coupler 31 for causing the probe light 5 to be incident inside the terahertz wave generating nonlinear crystal 1, and an imaging device 41. The imaging device 41 is characterized by imaging the detected Stokes light 6 generated by the interaction between the probe light 5 and the terahertz waves 3 generated by the terahertz wave generating nonlinear crystal 1.

The application discloses a device and method for generating 193nm waveband ultraviolet laser, which comprises a near-infrared laser driving unit 1, a nonlinear frequency conversion system 2 and an ultraviolet laser generating system 3 connected in sequence. The near-infrared laser driving unit is a high-power picosecond laser for generating near-infrared laser with a wavelength of 1064nm. The near-infrared laser is divided into two parts by a beam splitter, one part of which is used as pump light of a first optical parametric oscillator (OPO1) and generates 840nm laser, and the 840nm laser is converted into 210nm laser through four frequency doubling; the other part is directly used as pump light of a second optical parametric oscillator (OPO2) and generates 2380nm laser. In the last ultraviolet laser generating system, the 210nm laser and the 2380nm laser are combined through sum frequency mixing to finally realize the output of 193nm waveband ultraviolet laser. The application provides a new idea and technical route for the development of vacuum ultraviolet 193nm waveband solid-state laser by using mature nonlinear crystal and nonlinear frequency conversion process.

This invention discloses a high-power, broadband, tunable long-wavelength mid-infrared femtosecond laser generation device and method. The laser beam is split into a first beam and a second beam. The first beam pumps a first YAG crystal to generate a first supercontinuum, from which a signal light of a predetermined wavelength is selected. The signal light undergoes at least two cascaded optical parametric amplification stages to generate a high-power mid-infrared pump light. The second beam pumps a second YAG crystal to generate a second supercontinuum covering the long-wavelength infrared band as a seed light. This seed light is then incident on a BGGSe crystal for optical parametric amplification. Using a 1.5μm high-power femtosecond laser as the pump source, combined with the BGGSe nonlinear crystal for optical parametric amplification, the wide transmission range and high nonlinear coefficient of the BGGSe crystal are effectively utilized. Phase matching in the 6–18μm band can be achieved under 1.5μm pumping conditions, thereby obtaining a broadband, high-power, femtosecond-level laser output covering the long-wavelength mid-infrared band.

The application discloses a time entanglement two-photon generation system and a generation method. The generation system comprises a laser source, an equal-arm MZ interferometer, a circulating waveguide, an upper computer, a controller, a second-order nonlinear crystal and a light splitting module. The equal-arm MZ interferometer is composed of a first beam splitter, a second beam splitter and a phase modulator. The upper computer calculates the light intensity percentage of the sub-pulse output from the second beam splitter after the light pulse output by the laser source passes through the phase modulator based on the input parameters, and calculates the light intensity percentage of the sub-pulse output from the second beam splitter after the light splitting pulse in each cycle passes through the phase modulator. The controller correspondingly time-modulates the phase modulator based on the light intensity percentages, so that the light splitting pulse entering the circulating loop is output from the output lower port of the second beam splitter at a corresponding light intensity ratio. After multiple cycles, the sub-pulse sequence output is subjected to a spontaneous parametric down-conversion process by the second-order nonlinear crystal to generate entangled two photons.

A method for reverse virtual screening based on programmable quantum computing, characterized in that the method comprises the following steps: S1. Calculating a binding interaction graph of the given small molecule and the target protein molecule on the computer based on different pharmacophore distances for a given small molecule and a target protein molecule; S2. Encoding an adjacency matrix of the binding interaction graph into a platform for quantum-reverse virtual screening by decomposing the adjacency matrix; S3. Performing a Gaussian Bose scan over the platform for quantum-reverse virtual screening, which includes the following substeps: S31. Generating a set of single-mode vacuum compression states with different compression levels using the acousto-optic modulator to chop the pulsed laser to pump the nonlinear crystal, and sending the set of single-mode vacuum compression states into the cyclic optical path of the quantum processing unit module; S32. Performing a high-dimensional global primary state evolution operation by an electro-optic modulator in the cyclic optical path, and inputting the evolution result into the detection module, where the number of electro-optic modulators is two and the electro-optical modulator is equipped with a power amplifier for amplifying an analog signal and is controlled by a programmable arbitrary waveform generator; S33. Measuring the presence or absence of the number of photons in each mode by a single-photon superconducting detector in the detection module, and inputting the measurement result into the computer to obtain the sample result processed by the quantum algorithm; and S4. Generating all full-linkage subgraphs of the binding interaction graph according to the sampling results, and generating a full-linkage subgraph with the greatest weight by sorting all full-linkage subgraphs according to weight, thereby directly determining the optimal binding mode between the small molecule and the target protein molecule by the structure of the full-linkage subgraph with the greatest weight.

The application belongs to the technical field of deep ultraviolet laser, and provides a continuous deep ultraviolet laser and a working method for realizing walk-off elimination and aberration correction, which comprises a fundamental laser for outputting continuous single-frequency laser in a visible waveband and serving as an input light source for nonlinear conversion; a resonant frequency-doubling cavity which is a bow-tie type ring cavity and is composed of four mirrors; a temperature controller which is placed in the resonant frequency-doubling cavity and is located between a high-reflectivity curved mirror and a bichromatic aberration-corrected collimating output mirror, and is used for controlling the nonlinear crystal to work at an optimal temperature to realize maximum harmonic output of the nonlinear crystal; and a nonlinear crystal which is placed in the temperature controller and is used for outputting the generated frequency-doubled light from the bichromatic aberration-corrected collimating output mirror, and the fundamental light is reflected back to the coupling input mirror for resonant enhancement; wherein the positions of the four mirrors are set according to the resonant cavity stability conditions, so that the spot radii in the meridional direction and the sagittal direction are equal at the center of the nonlinear crystal. High-quality deep ultraviolet laser output is realized.

According to the present disclosure, a second mirror and a third mirror are disposed to face each other with a nonlinear crystal interposed therebetween. The second mirror and the third mirror reflect a laser beam multiple times therebetween, and respectively include a plurality of first points formed at equal intervals along an edge portion of the second mirror, and a plurality of second points formed at equal intervals along an edge portion of the third mirror, the plurality of first points and the plurality of second points being configured to cause reflections to occur between the second mirror and the third mirror in a preset sequence. The third mirror includes a hole through which a laser beam finally reflected via the second mirror is transmitted to the outside, wherein the laser beam forms a reciprocating path by alternately passing through the plurality of first points and the plurality of second points one by one while rotating in the clockwise direction or the counterclockwise direction.

The present application relates to a kind of Gaussian mirror unstable cavity optical parametric oscillator double-pass pumping structure and its building method, including the OPO input mirror, nonlinear crystal, OPO output coupling mirror, 45 degree beam splitter, concave lens, 0 degree high reflectivity lens placed in order along the light path in sequence;OPO input mirror and OPO output coupling mirror are curved mirror, the curvature of OPO input mirror is R1, the curvature of OPO output coupling mirror is R2, R1 is positive, R2 is negative.The present application is based on the defect of existing unstable cavity Gaussian output mirror coating technology to realize double-pass pumping structure, innovatively proposes cavity mirror combination idea, uses 45 degree beam splitter and 0 degree high reflectivity lens combination, realizes pump light double-pass pumping, innovatively adds concave lens in pump light return light path to compensate the focusing effect caused by unstable cavity lens, improves the output energy of signal light and idler light, expands the application scenario of Gaussian mirror unstable cavity optical parametric oscillator.

A terahertz wave generating device is designed in such a manner as to include: a pulsed light source that outputs pulsed light; a first nonlinear crystal that converts the pulsed light output from the pulsed light source into signal light and idler light, and outputs the converted signal light and the converted idler light; an etalon that transmits a plurality of light beams having frequencies different from each other, having been given the converted signal light and the converted idler light from the first nonlinear crystal; and a second nonlinear crystal that generates terahertz waves having a frequency corresponding to a frequency difference between light beams among the plurality of light beams transmitted through the etalon.

The invention relates to a pure Rayleigh scattering signal acquisition method and system based on a laser source. The method comprises the following steps: performing beam splitting treatment on femtosecond pulses output by a laser source to obtain at least two beams of femtosecond pulses; inputting the first beam of femtosecond pulse into a nonlinear crystal for frequency mixing processing to obtain a preprocessed scattering signal; performing frequency shift processing on the second beam of femtosecond pulse by using an acousto-optic frequency shifter or performing phase lock processing on the second beam of femtosecond pulse by using an optical phase lock ring to obtain a coherent local oscillator signal; inputting the preprocessed scattering signal and the coherent local oscillator signal into a frequency mixer for interference processing to obtain a mixed difference frequency signal; and performing multi-stage signal processing on the mixed difference frequency signal by using a signal processor to obtain a target Rayleigh scattering signal. According to the invention, the Rayleigh scattering signal acquisition accuracy can be improved.

A method for growing a periodically polarized nonlinear crystal may include placing a seed crystal in a melt to form a seed crystal melt mixture, the seed crystal comprising at least one of strontium tetraborate (SBO) or lithium triborate (LBO), and the melt comprising at least one of a mixture of Sr, B, and O or a mixture of Li, B, and O. The method may further include heating the seed crystal melt mixture to a predetermined temperature until a periodically polarized nonlinear crystal is formed.

The present application relates to a kind of light beam pointing stability large rotation angle tuning short wave infrared coherent light source, and the present coherent light source includes: pump laser, magneto-optical isolator, condensing lens group, two 45 ° reflector, optical parametric oscillator (OPO), optical filter, fixed right-angle prism and mobile right-angle prism.The pump laser is used to generate pump light;The magneto-optical isolator is used to ensure one-way transmission of laser;The condensing lens group is used to improve beam energy density;Two 45 ° reflector is used to fold pump light path;The optical parametric oscillator is used to generate coherent short wave infrared light;The nonlinear crystal is used to adjust the output wavelength of short wave infrared light source;The optical filter is used to block remaining pump light;Fixed right-angle prism and displacement right-angle prism are used to compensate the lateral displacement of output beam caused in the process of crystal rotation.The present application compensates the lateral displacement of light beam by moving prism, realizes the position of output beam unchanged in the process of large rotation angle tuning, ensures its directionality stability, and is suitable for spectral analysis, remote sensing and imaging and other needs.

Improved receiving device for a ground-to-surface interface of a quantum information network. This device (10) comprises: an optical unit (11) for capturing an entangled photon emitted at an emission frequency ( ) from a satellite (3), a frequency converter (16), and a quantum memory (14) for storing entangled photons, the frequency converter comprising: a nonlinear crystal (50); a tunable source (52); and control means (54) for the tunable source, the nonlinear crystal generating a secondary entangled photon from the captured entangled photon and a conversion photon generated by the tunable source, the control means controlling the tunable source to modify a generation frequency of the conversion photon so that the secondary entangled photon is compatible with the quantum memory, while the captured entangled photon has its emission frequency affected by a Doppler shift due to the satellite's movement.Figure for the abbreviation: Figure 1.