Janis Alnis

Quantum Optics laboratory Institute of Atomic Physics, University of Latvia

Visit from the Chinese Academy of Sciences, Center for Space Utilisationhttp://english.csu.cas.cn

Feb. 24, 2015, Riga

Email: janis.alnis@lu.lv http://asi.lv/New/Quantum%20Optics%20Lab%20Riga.pdf

• Photon is a quantum of light. • Wave – particle dualism of a photon: “clicks” and interference • Quantum Optics – most recent category.• Lasers important QO tool: controled wavelength, pulse length, large intensities, directionality.

Femtosecond laser frequency comb

• A tool to count precisely optical frequencies against RF clocks. Nobel Prizes 2005 and 2012.• fs combs produced a revolution in optical clocks.• fr and fo frequencies must be measured.• Optical clock accuracy in 2015 is 18 digits.

Importance of excellent research trainingInstitute of Quantum Optics, Garching, DE

Group of Prof. T. Hansch, Nobel prize 2005 winner

Collaboration with MPQ GarchingH spectroscopy, Prof. T. Hansch group

INNOVATION - transportable optical reference resonators

Repeated in: MPQ, PTB, ETH, Singapure, CERN, Lebedev inst.Commercialized by : Menlo Systems un Stable lasers.

Collaboration with ETH Zurich Positronium (Ps) 1S-2S spectrocopy

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Equipment:• Femtosecond optical frequency comb (Menlo Systems) to count optical frequencies• Two diode laser systems 780 and 980 nm stabilized on Fabry-Perot resonators• Rubidium optical saturation setup• GPS time receiver, rubidium radiofrequency clock

Knowledge transfer to the regions of EuropeQuantum Optics Laboratory in Riga

founded in 2013 within a project FOTONIKA-LV

Research in the Q-O Laboratory

• Measure stable optical frequencies using a fs frequency comb.

• Improve optical frequency references: Rb, Te2, I2, FP resoators.

• Compare with RF standards: GPS, GLONAS, Rb RF clock.

• Distribute optical frequencies via fiber and free space.

•Distance ranging with a fs laser.

• Observations of atmosphere and air quality, Internet sensors.

Precision measurement system of light frequency

fs optical frequency comb in Q-O lab• Erbium fiber based 150 fs, 1500±20 nm. Repetition rate 250 MHz.• Output amplified by two Er fiber optical amplifiers.• Spektrum broadening in photonic crystal fiber 1000...2200 nm.• f - 2f interferometer 2200 nm 2 = 1100 nm.• Visible output after frequency doubler 500 nm … 1000 nm.• Made by ”Menlo Systems” Munich, Prof. T. Hansch spin-off.• A 210 kEUR investment within FOTONIKA-LV project in 2013.

Laser stabilization resonators from low-expansion glass

Broadband Zerodur FP rezonator for laser stabilization below 1 kHz linewidth with <100 Hz/s drift and reduced sensitivity to vibrations

K. Bluss, A. Atvars, I. Brice, J. Alnis, Latv . J. Physics (2015).

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Beat note frequency - const, kHz

Optical beat note of stabilized laser

Optical frequency standard using Rb 780 nm transitionSaturation spectroscopy

11 digits stability

Radiofrequency Rb clock calibration using GNSS time

Connor Winfried CW742-ND.GPS only

Simple receiver: Texim Nastar GPS+GLONAS

Quantum Optics Lab people 2015

• Dr. Janis Alnis, group Leader, repatriated from Germany• Dr. Ilja Fescenko, repatriated from Switzerland • Dr. Christina Andreva-Markova, visiting scientist, Bulgaria• Dr. Asparux Markov, visiting scientist, Bulgaria• Dr. Nikolay Bezuglov, visiting scientist, Russia• MSc Inga Brice, PhD student• MSc Aigars Apsitis, technical assistance• Jāzeps Rutkis, physics bachelor student• Alma Ūbele, physics bachelor student

Thank you for attention!