用于Hg原子光晶格钟的低漂移率超稳腔系统
|
摘要
光晶格钟需要高稳定度的超稳激光,而超稳激光的频率稳定性受限于超稳腔的热噪声和温度涨落,因此,降低超稳腔的温度涨落对于超稳激光的频率噪声达到热噪声极限具有重要意义。分别从时域和频域上分析了达到热噪声极限对超稳腔温度稳定性的要求,设计了超稳腔控温系统,其包括一层被动隔热、两层主动控温的超稳腔真空系统和主动控温装置;找到了超稳腔的零膨胀工作温度;测量了真空隔热系统的温度传递时间常数(3.6d);监测了真空腔内主动控温层11d的温度涨落(<1mK)。通过实验测量和理论分析,在频域和时域上分别计算得到了超稳腔的温度波动,确定了千秒内的温度涨落引起的频率噪声均在热噪声极限以下。利用磁光阱产生的199 Hg冷原子的钟频跃迁光谱测得超稳腔的长期温度漂移为4.2kHz/d,符合Hg原子光晶格钟的要求。
The ultra-stable laser is a key component in optical lattice clock,whose frequency stability is limited by the thermal noise and affected by the temperature fluctuation of ultra-stable cavity.Thus the temperature fluctuation is a serious obstacle in pursuing thermal-noise-limit of ultra-stable laser.In this paper,we analyze the requirement of the temperature stability to reach the thermal-noise-limit in frequency domain and time domain,and design the thermal-isolation vacuum system(with one passive thermal shield layer and two active temperature stabilized layers)and the corresponding temperature controller.Having developed the ultra-stable cavity system,we measure the zero-expansion work temperature of the ultra-stable cavity,the temperature transferring time constant of the thermal shield(3.6 d),and the temperature fluctuation of the temperature stabilized layer in vacuum in 11 d(<1 mK).With these data,we calculate the temperature fluctuation of the ultra-stable cavity,and evaluate that the frequency noise induced from the temperature fluctuation which is all below the thermal-noise-limit in 1000 sintegration time.Moreover,we also use the clock transition spectrum of the 199 Hg cold atoms in magneto-optical trap to measure the long-term drift rate of the ultra-stable cavity(4.2 kHz/d).This frequency drift rate of ultra-stable cavity is competent to mercury optical lattice clock.
The ultra-stable laser is a key component in optical lattice clock,whose frequency stability is limited by the thermal noise and affected by the temperature fluctuation of ultra-stable cavity.Thus the temperature fluctuation is a serious obstacle in pursuing thermal-noise-limit of ultra-stable laser.In this paper,we analyze the requirement of the temperature stability to reach the thermal-noise-limit in frequency domain and time domain,and design the thermal-isolation vacuum system(with one passive thermal shield layer and two active temperature stabilized layers)and the corresponding temperature controller.Having developed the ultra-stable cavity system,we measure the zero-expansion work temperature of the ultra-stable cavity,the temperature transferring time constant of the thermal shield(3.6 d),and the temperature fluctuation of the temperature stabilized layer in vacuum in 11 d(<1 mK).With these data,we calculate the temperature fluctuation of the ultra-stable cavity,and evaluate that the frequency noise induced from the temperature fluctuation which is all below the thermal-noise-limit in 1000 sintegration time.Moreover,we also use the clock transition spectrum of the 199 Hg cold atoms in magneto-optical trap to measure the long-term drift rate of the ultra-stable cavity(4.2 kHz/d).This frequency drift rate of ultra-stable cavity is competent to mercury optical lattice clock.
引文
[1]McFerran J J,Yi L,Mejri S,et al.Neutral atom frequency reference in the deep ultraviolet with fractional uncertainty=5.7×10-15[J].Physical Review Letters,2012,108(18):1803004.
[2]Nicholson T L,Campbell S L,Hutson R B,et al.Systematic evaluation of an atomic clock at 2×10-18total uncertainty[J].Nature Communications,2015,6(1):6896.
[3]Ushijima I,Takamoto M,Das M,et al.Cryogenic optical lattice clocks[J].Nature Photonics,2015,9(3):185-189.
[4]Abgrall M,Chupin B,de Sarlo L,et al.Atomic fountains and optical clocks at SYRTE:status and perspectives[J].Comptes Rendus Physique,2015,16(5):461-470.
[5]Hinkley N,Sherman J A,Phillips N B,et al.An atomic clock with 10-18 instability[J].Science,2013,341(6151):1215-1218.
[6]Schioppo M,Brown R C,McGrew W F,et al.Ultrastable optical clock with two cold-atom ensembles[J].Nature Photonics,2016,11(1):48-52.
[7]Peil S,Hanssen J L,Swanson T B,et al.Evaluation of long term performance of continuously running atomic fountains[J].Metrologia,2014,51(3):263-269.
[8]Dong G X,Lin J D,Zhang S,et al.Research on atomic phase feedback in pulsed optically pumped atomic clocks[J].Acta Optica Sinica,2017,37(7):0702001.董功勋,林锦达,张松,等.脉冲光抽运原子钟原子相位反馈研究[J].光学学报,2017,37(7):0702001.
[9]Liu P,Cheng H D,Meng Y L,et al.Research on phase modulation of Ramsey fringes in integrating sphere cold atom clocks[J].Chinese Journal of Lasers,2016,43(11):1112001.刘鹏,成华东,孟艳玲,等.积分球冷原子钟相位调制Ramsey条纹研究[J].中国激光,2016,43(11):1112001.
[10]Huntemann N,Sanner C,Lipphardt B,et al.Singleion atomic clock with 3×10-18 systematic uncertainty[J].Physical Review Letters,2016,116(6):063001.
[11]Huang Y,Guan H,Liu P,et al.Frequency comparison of two 40 Ca+optical clocks with an uncertainty at the 10-17 level[J].Physical Review Letters,2016,116(1):013001.
[12]Chou C W,Hume D B,Koelemeij J C J,et al.Frequency comparison of two high-accuracy Al+optical clocks[J].Physical Review Letters,2010,104(7):070802.
[13]Beloy K P,Hinkley N M,Phillips N B,et al.Atomic clock with 1×10-18 room-temperature blackbody stark uncertainty[J].Physical Review Letters,2014,113(26):260801.
[14]Porsev S G,Derevianko A.Multipolar theory of blackbody radiation shift of atomic energy levels and its implications for optical lattice clocks[J].Physical Review A,2006,74(2):020502.
[15]Rosenband T,Schmidt P O,Hume D B,et al.Observation of the 1 S0→3 P0clock transition in 27 Al+[J].Physical Review Letters,2007,98(22):220801.
[16]Young B C,Cruz F C,Itano W M,et al.Visible lasers with subhertz linewidths[J].Physical Review Letters,1999,82(19):3799-3802.
[17]Drever R W P,Hall J L,Kowalski F V,et al.Laser phase and frequency stabilization using an optical resonator[J].Applied Physics B,1983,31(2):97-105.
[18]Numata K,Kemery A,Camp J.Thermal-noise limit in the frequency stabilization of lasers with rigid cavities[J].Physical Review Letters,2004,93(25):250602.
[19]Martin M J.Quantum metrology and many-body physics:pushing the frontier of the optical lattice clock[D].Colorado:University of Colorado,2013:67-89.
[20]Zhang J,Wu W,Shi X H,et al.Design verification of large time constant thermal shields for optical reference cavities[J].Review of Scientific Instruments,2016,87(2):023104.
[21]Bergquist J C,Itano W M,Wineland D J.Laser stabilization to ion[C]∥Hansch T W,Inguscio M.Proceedings of the International School of Physics《Enrico Fermi》.1994:359-376.
[22]Liu Y.Sub-mK temperature control for ultrastable laser systems[D].Wuhan:Huazhong University of Science and Technology,2015:11-12.刘洋.超稳激光中亚毫开尔文量级温度的精密控制[D].武汉:华中科技大学,2015:11-12.
[23]Prestage J D,Dick G J,Maleki L.The JPL trapped ion frequency standard development[C]∥Proceedings of the 19th Annual Precise Time and Time Interval Systems and Applications Meeting.1987:285-297.
[24]Santarelli G,Audoin C,Makdissi A,et al.Frequency stability degradation of an oscillator slaved to a periodically interrogated atomic resonator[J].IEEE Transactions on Ultrasonics,Ferroelectrics,and Frequency Control,1998,45(4):887-894.
[25]Quessada A,Kovacich R P,Courtillot I N,et al.The Dick effect for an optical frequency standard[J].Journal of Optics B:Quantum and Semiclassical Optics,2003,5(2):S150-S154.
[26]Jiang H F.Development of ultra-stable laser sources and long-distance optical link via telecommunication networks[D].Paris:University of Paris,2010:22-23.
[27]Madhavan U P K,Gunasekaran M K,Kumar A.±30μK temperature controller from 25to 103℃:study and analysis[J].Review of Scientific Instruments,2003,74(1):231-242.
[28]Wu L F,Jiang Y Y,Ma C Q,et al.0.26-Hzlinewidth ultrastable lasers at 1557nm[J].Scientific Reports,2016,6:24969.
[29]Chen H Q.Research on the key technology of the optical frequency synthesis[D].Shanghai:East China Normal University,2014:32-33.陈海琴.光学频率合成关键技术研究[D].上海:华东师范大学,2014:32-33.
[30]Bian W,Huang Y,Guan H,et al.1Hz linewidth Tisapphire laser as local oscillator for 40 Ca+optical clocks[J].Review of Scientific Instruments,2016,87(6):063121.
[31]Liu H,Zhang X,Jiang K L,et al.Realization of closed-loop operation of optical lattice clock based on171 Yb[J].Chinese Physics Letters,2017,34(2):020601.
[32]Liu H L,Yin S Q,Liu K K,et al.Magneto-optical trap for neutral mercury atoms[J].Chinese Physics B,2013,22(4):043701.
[33]Liu K K,Zhao R C,Gou W,et al.A single folded beam magneto-optical trap system for neutral mercury atoms[J].Chinese Physics Letters,2016,33(7):070602.
[34]Alnis J,Matveev A,Kolachevsky N,et al.Subhertz linewidth diode lasers by stabilization to vibrationally and thermally compensated ultralow-expansion glass Fabry-Pérot cavities[J].Physical Review A,2008,77(5):053809.
[2]Nicholson T L,Campbell S L,Hutson R B,et al.Systematic evaluation of an atomic clock at 2×10-18total uncertainty[J].Nature Communications,2015,6(1):6896.
[3]Ushijima I,Takamoto M,Das M,et al.Cryogenic optical lattice clocks[J].Nature Photonics,2015,9(3):185-189.
[4]Abgrall M,Chupin B,de Sarlo L,et al.Atomic fountains and optical clocks at SYRTE:status and perspectives[J].Comptes Rendus Physique,2015,16(5):461-470.
[5]Hinkley N,Sherman J A,Phillips N B,et al.An atomic clock with 10-18 instability[J].Science,2013,341(6151):1215-1218.
[6]Schioppo M,Brown R C,McGrew W F,et al.Ultrastable optical clock with two cold-atom ensembles[J].Nature Photonics,2016,11(1):48-52.
[7]Peil S,Hanssen J L,Swanson T B,et al.Evaluation of long term performance of continuously running atomic fountains[J].Metrologia,2014,51(3):263-269.
[8]Dong G X,Lin J D,Zhang S,et al.Research on atomic phase feedback in pulsed optically pumped atomic clocks[J].Acta Optica Sinica,2017,37(7):0702001.董功勋,林锦达,张松,等.脉冲光抽运原子钟原子相位反馈研究[J].光学学报,2017,37(7):0702001.
[9]Liu P,Cheng H D,Meng Y L,et al.Research on phase modulation of Ramsey fringes in integrating sphere cold atom clocks[J].Chinese Journal of Lasers,2016,43(11):1112001.刘鹏,成华东,孟艳玲,等.积分球冷原子钟相位调制Ramsey条纹研究[J].中国激光,2016,43(11):1112001.
[10]Huntemann N,Sanner C,Lipphardt B,et al.Singleion atomic clock with 3×10-18 systematic uncertainty[J].Physical Review Letters,2016,116(6):063001.
[11]Huang Y,Guan H,Liu P,et al.Frequency comparison of two 40 Ca+optical clocks with an uncertainty at the 10-17 level[J].Physical Review Letters,2016,116(1):013001.
[12]Chou C W,Hume D B,Koelemeij J C J,et al.Frequency comparison of two high-accuracy Al+optical clocks[J].Physical Review Letters,2010,104(7):070802.
[13]Beloy K P,Hinkley N M,Phillips N B,et al.Atomic clock with 1×10-18 room-temperature blackbody stark uncertainty[J].Physical Review Letters,2014,113(26):260801.
[14]Porsev S G,Derevianko A.Multipolar theory of blackbody radiation shift of atomic energy levels and its implications for optical lattice clocks[J].Physical Review A,2006,74(2):020502.
[15]Rosenband T,Schmidt P O,Hume D B,et al.Observation of the 1 S0→3 P0clock transition in 27 Al+[J].Physical Review Letters,2007,98(22):220801.
[16]Young B C,Cruz F C,Itano W M,et al.Visible lasers with subhertz linewidths[J].Physical Review Letters,1999,82(19):3799-3802.
[17]Drever R W P,Hall J L,Kowalski F V,et al.Laser phase and frequency stabilization using an optical resonator[J].Applied Physics B,1983,31(2):97-105.
[18]Numata K,Kemery A,Camp J.Thermal-noise limit in the frequency stabilization of lasers with rigid cavities[J].Physical Review Letters,2004,93(25):250602.
[19]Martin M J.Quantum metrology and many-body physics:pushing the frontier of the optical lattice clock[D].Colorado:University of Colorado,2013:67-89.
[20]Zhang J,Wu W,Shi X H,et al.Design verification of large time constant thermal shields for optical reference cavities[J].Review of Scientific Instruments,2016,87(2):023104.
[21]Bergquist J C,Itano W M,Wineland D J.Laser stabilization to ion[C]∥Hansch T W,Inguscio M.Proceedings of the International School of Physics《Enrico Fermi》.1994:359-376.
[22]Liu Y.Sub-mK temperature control for ultrastable laser systems[D].Wuhan:Huazhong University of Science and Technology,2015:11-12.刘洋.超稳激光中亚毫开尔文量级温度的精密控制[D].武汉:华中科技大学,2015:11-12.
[23]Prestage J D,Dick G J,Maleki L.The JPL trapped ion frequency standard development[C]∥Proceedings of the 19th Annual Precise Time and Time Interval Systems and Applications Meeting.1987:285-297.
[24]Santarelli G,Audoin C,Makdissi A,et al.Frequency stability degradation of an oscillator slaved to a periodically interrogated atomic resonator[J].IEEE Transactions on Ultrasonics,Ferroelectrics,and Frequency Control,1998,45(4):887-894.
[25]Quessada A,Kovacich R P,Courtillot I N,et al.The Dick effect for an optical frequency standard[J].Journal of Optics B:Quantum and Semiclassical Optics,2003,5(2):S150-S154.
[26]Jiang H F.Development of ultra-stable laser sources and long-distance optical link via telecommunication networks[D].Paris:University of Paris,2010:22-23.
[27]Madhavan U P K,Gunasekaran M K,Kumar A.±30μK temperature controller from 25to 103℃:study and analysis[J].Review of Scientific Instruments,2003,74(1):231-242.
[28]Wu L F,Jiang Y Y,Ma C Q,et al.0.26-Hzlinewidth ultrastable lasers at 1557nm[J].Scientific Reports,2016,6:24969.
[29]Chen H Q.Research on the key technology of the optical frequency synthesis[D].Shanghai:East China Normal University,2014:32-33.陈海琴.光学频率合成关键技术研究[D].上海:华东师范大学,2014:32-33.
[30]Bian W,Huang Y,Guan H,et al.1Hz linewidth Tisapphire laser as local oscillator for 40 Ca+optical clocks[J].Review of Scientific Instruments,2016,87(6):063121.
[31]Liu H,Zhang X,Jiang K L,et al.Realization of closed-loop operation of optical lattice clock based on171 Yb[J].Chinese Physics Letters,2017,34(2):020601.
[32]Liu H L,Yin S Q,Liu K K,et al.Magneto-optical trap for neutral mercury atoms[J].Chinese Physics B,2013,22(4):043701.
[33]Liu K K,Zhao R C,Gou W,et al.A single folded beam magneto-optical trap system for neutral mercury atoms[J].Chinese Physics Letters,2016,33(7):070602.
[34]Alnis J,Matveev A,Kolachevsky N,et al.Subhertz linewidth diode lasers by stabilization to vibrationally and thermally compensated ultralow-expansion glass Fabry-Pérot cavities[J].Physical Review A,2008,77(5):053809.