CN218940306U

CN218940306U - FPGA laser frequency stabilizing device based on ARTIQ

Info

Publication number: CN218940306U
Application number: CN202223049941.3U
Authority: CN
Inventors: 乐虹伶; 邵虎; 管桦; 黄垚; 高克林
Original assignee: Institute of Precision Measurement Science and Technology Innovation of CAS
Current assignee: Institute of Precision Measurement Science and Technology Innovation of CAS
Priority date: 2022-11-14
Filing date: 2022-11-14
Publication date: 2023-04-28
Anticipated expiration: 2032-11-14

Abstract

The utility model discloses a laser frequency stabilizing device based on ARTIQ control, which comprises a laser to be stabilized, wherein an isolator, a half wave plate and a polarization beam splitter are sequentially arranged on a laser emergent light path of the laser to be stabilized, the polarization beam splitter is connected with an optical fiber inlet corresponding to a multipath expansion channel of a wavelength meter through an optical fiber, the wavelength meter is connected with a computer, the computer is connected with an ARTIQ control system, and the ARTIQ control system is connected with piezoelectric ceramics of the laser to be stabilized. The locking precision of each path of laser to be stabilized can reach within 1MHz, the experimental cost is reduced, the experimental space is saved, the frequency locking of multiple paths of laser to be stabilized can be realized at the same time, the frequency stabilizing element is simplified, and the integration and the miniaturization are facilitated.

Description

FPGA laser frequency stabilizing device based on ARTIQ

Technical Field

The utility model relates to the field of laser frequency stabilization, in particular to an FPGA laser frequency stabilization device based on ARTIQ. The laser frequency stabilizing device is suitable for laser frequency stabilization.

Background

In recent years, along with the rapid development of laser technology, the laser technology is promoted to be widely applied in a plurality of fields, especially in experiments of interaction of atoms or molecules and laser, such as atom and molecule physics, laser spectrum, optical frequency scale, quantum information and the like, and the laser technology has higher requirements on the stability of laser frequency. In the optical frequency scale experiment, the interaction between the laser with stable multiple frequencies and the trapped ions or neutral atoms is required, the short-term stability and the long-term stability of the related cooling, pumping and quenching lasers are required to be smaller than the natural line width (generally smaller than 20 MHz), and most of commercial semiconductor lasers cannot directly meet the experiment requirement and are required to perform frequency stabilization operation in the experiment technology. The current common laser frequency stabilization mode mainly comprises a point-Drever-Hall (PDH) frequency stabilization based on an ultra-stable cavity, a wavelength modulation frequency stabilization based on a transmission cavity, an error feedback control frequency stabilization based on a wavelength meter and the like. When the drift and jitter of the laser after the frequency stabilization are smaller than 1MHz, the long-term continuous operation of the optical frequency scale is hardly affected. In addition, experiments require that the laser frequency lock has anti-interference capability, namely, the laser frequency can still be locked when the external environment (such as temperature and vibration) changes.

Laser frequency stabilization is always a key technology in the laser application field, and besides the three frequency stabilization modes, the laser frequency stabilization method further comprises the following steps: saturated absorption spectrum frequency stabilization, modulation transfer spectrum frequency stabilization, dual-color laser frequency stabilization, frequency-voltage conversion frequency stabilization, etc. [ Gong, etc. ], semiconductor laser frequency stabilization review [ J ],2019, 1674-5795]. The practicality and the application fields of different frequency stabilization technologies are different, and the traditional frequency stabilization methods such as saturated absorption spectrum, ultra-stable cavity, wavelength modulation and modulation spectrum are basically all based on physical optical theory and are realized through an optical system and related photoelectron components, so that the defects of higher experimental cost and larger occupied space generally exist. The PDH frequency stabilization depends on accessories such as a high-definition F-P cavity, an electro-optical modulator, a reference signal source and the like, can meet the requirement of ultra-narrow linewidth of laser, is the technology with the widest application and the highest frequency stabilization performance at present, but has the defects of higher cost and large occupied volume, the long-term stability of the locking frequency depends on the temperature drift of the used ultra-cavity, and has no absolute frequency reference value, so that the application of the locking frequency in an integrated and portable optical frequency scale is limited. Later, the widespread use of wavemeters began application of error feedback based on frequency-to-voltage conversion to laser frequency-locking techniques. The basic principle is that the frequency of laser is read out in real time by using a wavemeter, the frequency is compared with an ideal set frequency to obtain a deviation value, then the frequency error is converted into voltage feedback and output to the current of the laser or piezoelectric ceramics (PZT), and a closed-loop feedback control system is utilized to maintain the long-term stability of the frequency. At present, a program development environment LabVIEW developed by the National Instruments (NI) company is used in a frequency stabilization system based on a wavelength meter, but the algorithm is not efficient under a LabVIEW platform, and if hardware equipment of the NI company is used, an NI board card matched with the hardware equipment is needed to interact with a computer. For example: in (Li Min, zhang Yong, peng Wencui, tong Xin), external cavity semiconductor laser long-term frequency stabilization system based on precision wavemeter [ J ], quantum electronics, 2017, 34 (04): 432-435), the wavelength is read using LabVIEW language and the piezoelectric controller BPC301 is controlled to output feedback, and the response speed of the LabVIEW and the feedback signal output by the piezoelectric controller limits the accuracy of the frequency stabilization. In (Guo Jixin, shoujie, cheng Xuewu, lin Zhaoxiang, wu Jinquan, 1319nm seed laser frequency stabilization control [ J ], optical and optoelectronic technology, 2022, 1672-3392), although laser frequency stabilization control system software was designed based on the Python language, feedback voltage output provided analog voltage using DAC system of NI6216 series produced by NI company, which requires interaction with a computer using LabVIEW platform. Although LabVIEW and Python can realize the calling of the program, the method is limited by the response speed of the feedback signal, and the frequency stabilization precision is limited as a result, and only reaches 20MHz.

Disclosure of Invention

The utility model aims to solve the problems in the prior art and provides an FPGA laser frequency stabilizing device based on ARTIQ.

The above object of the present utility model is achieved by the following technical means:

the utility model provides a FPGA laser frequency stabilization device based on ARTIQ, includes treats the frequency stabilization laser, all set gradually isolator, half wave plate and polarization beam splitter on treating the laser outgoing optical path of frequency stabilization laser, polarization beam splitter passes through the optical fiber entry that the multichannel extension passageway of optical fiber connection wavelength meter corresponds, the wavelength meter is connected with the computer, computer and ARTIQ control system are connected, ARTIQ control system and treat the piezoceramics connection of frequency stabilization laser.

As described above, the number of the lasers to be stabilized is multiple, and the isolator, the half wave plate and the polarization beam splitter are sequentially arranged on the laser emergent light path of each laser to be stabilized.

Compared with the prior art, the utility model has the following beneficial effects:

1. the locking precision of each path of laser to be stabilized can reach within 1MHz, and the laser locking device can be used for laser experiments with line width required to be 1MHz, can avoid using an ultra-complex optical ultra-stable cavity, simplifies the optical path and circuit of experimental operation, and can be used for precisely measuring spectrum, quantum information and other relevant experimental fields;

2. the utility model solves the defects of complex circuit and the like of the traditional PDH laser frequency stabilization device by adopting the ARTIQ control system, reduces the experiment cost, saves the experiment space, can simultaneously realize the frequency locking of multiple paths of lasers to be stabilized, simplifies the frequency stabilization element, ensures the stable operation by the modularized packaging of the ARTIQ control system, has small volume, is beneficial to integration and miniaturization, and can be used as the frequency stabilization device of the portable optical clock.

Drawings

FIG. 1 is a schematic diagram of the operation of the present utility model;

FIG. 2 is a graph of the frequency lock error output of a laser to be stabilized in the case of frequency stabilization; (a) Outputting a graph for the frequency error of the short-term locking of the laser to be stabilized; (b) Outputting a graph for the frequency error of the long-term locking of the laser to be stabilized;

fig. 3 is a graph of the frequency error output of the laser to be stabilized in the case of non-stabilized frequency.

In the figure: 111-a laser to be stabilized; 112-an isolator; 113-half wave plate; 114-polarization beam splitters; 115-wavelength meter; 16-a computer; 117-ARTIQ control system.

Detailed Description

The utility model will be further described in detail below in conjunction with examples to facilitate understanding and practicing the utility model by those of ordinary skill in the art, it being understood that the examples described herein are for the purpose of illustration and explanation only and are not intended to limit the utility model thereto.

As shown in fig. 1, an art q-based FPGA laser frequency stabilization device includes a laser 111 to be stabilized, an isolator 112, a half-wave plate 113, a polarization beam splitter 114, a wavemeter 115, a computer 116, and an art q control system 117.

The laser to be stabilized output by the laser to be stabilized 111 is coupled into an optical fiber after passing through an isolator 112, a half wave plate 113 and a polarization beam splitter PBS114 in sequence, the polarization beam splitter 114 is connected with an optical fiber inlet corresponding to a multipath expansion channel of a wavelength meter 115 through the optical fiber, and the wavelength meter 115 is connected with a computer 116. The computer 116 is provided with wavemeter operation software, the wavemeter operation software is the existing software, the wavemeter operation software is opened, and the computer 116 can display the real-time frequency and mode of the multipath laser to be stabilized collected by the optical fiber connection wavemeter 115. The computer 116 is connected with the ARTIQ control system 117, the computer 116 collects the frequency of the laser to be stabilized in real time and sends the difference between the frequency and the preset frequency to the ARTIQ control system 117, and the ARTIQ control system outputs feedback voltage to the piezoelectric ceramic PZT of the laser to be stabilized. The ARTIQ control system is a control system specially developed for ion related experiments and is produced by M-labs company, wherein a module comprises a main board (model: sinara 1124processor 'Kasli' 2.0) which can be used as independent core equipment to realize distributed real-time input and output; the radio frequency output module (model: 44710 DDS "Urukul" AD9910, AD 9912) can be used for modulating the frequency and power of laser; logic gate level output module (model 2128SMATTL card); a voltage output module (model: 5432DAC "Zotino"); the voltage signal reads the module (model: sampler ADC). The ARTIQ system has a unified graphical operation interface, is simpler and faster than the traditional LabView, and is provided with a 16-path DDS frequency synthesizer which can provide micro-hertz frequency resolution, and the switching time of the 16-path TTL can be controlled at ns level. The voltage output module (5432 DAC 'Zoino') is used for feeding back the signal with response time of 30us, and the related requirements of experiments such as optical frequency scale and quantum information can be completely met.

Preferably, the number of the lasers 111 to be stabilized is multiple, and an isolator 112, a half wave plate 113 and a polarization beam splitter 114 are sequentially arranged on a laser emergent light path of each laser 111 to be stabilized, and the polarization beam splitter 114 is connected with an optical fiber inlet corresponding to a multipath expansion channel of the wavelength meter 115 through an optical fiber.

The present utility model can realize the frequency stabilization of 1-8 lasers 111 to be stabilized, in this embodiment, the lasers 111 to be stabilized are 935nm lasers manufactured by beijing you optical science and technology limited, fig. 2 is an effect diagram of short-term locking and long-term locking of 935nm lasers manufactured by beijing you optical science and technology limited, the present utility model can be operated for a long period of time, the above 935nm lasers are locked for more than 30 days in laboratory (from 2022, 8, 9, to 2022, 11, 7, and still perform frequency stabilization at present). Wherein the absolute accuracy of the wavemeter 115 (model WS-7) is 60MHz, the fast coupling ratio is 150MHz, and the measurement resolution is 10MHz.

The ARTIQ control system 117 has 16 voltage output interfaces, so that the frequency stabilization of multiple laser beams can be realized at the same time. The accuracy of the wavemeter 115 and the performance of the laser 111 to be stabilized can influence the frequency stabilizing effect, and the utility model can realize the frequency stabilization of the laser of the multiple paths of lasers 111 to be stabilized. The short-term frequency jitter after laser stabilization is within 1MHz and the long-term jitter is about 10MHz, as shown in fig. 2. Under the same experimental environment, the shift of the frequency variation of the non-stabilized laser in one hour is about 200MHz, as shown in fig. 3.

The specific embodiments described herein are offered by way of illustration only. Those skilled in the art may make various modifications or additions to the described embodiments or substitutions thereof without departing from the spirit of the utility model or exceeding the scope of the utility model as defined in the accompanying claims.

Claims

1. FPGA laser frequency stabilization device based on ARTIQ, including waiting for stabilizing frequency laser instrument (111), its characterized in that, all set gradually isolator (112), half wave plate (113) and polarization beam splitter (114) on waiting for the laser exit optical path of stabilizing frequency laser instrument (111), polarization beam splitter (114) are through the optical fiber entry that multichannel expansion passageway corresponds of optical fiber connection wavelength meter (115), wavelength meter (115) are connected with computer (116), and computer (116) are connected with ARTIQ control system (117), and ARTIQ control system (117) are connected with the piezoceramics who waits for stabilizing frequency laser instrument (111).

2. The FPGA laser frequency stabilization device based on ARTIQ according to claim 1, wherein the number of the lasers (111) to be stabilized is plural, and an isolator (112), a half wave plate (113) and a polarization beam splitter (114) are sequentially disposed on the laser outgoing optical path of each laser (111) to be stabilized.