|Prof. Nicolò Beverini – Department of Physics, University of Pisa and INFN, sezione di Pisa, Pisa, Italy – Senior Member of the Optical Society of America
LECTURE: “Optical gyroscopes: application to Geodesy, Earth Science, and Fundamental Physics”
George Sagnac in 1913 showed that light traveling along a closed-ring path in opposite directions allows detecting the rotational speed of the ring structure with respect to inertial space. Michelson was able a few years later to measure with a very large interferometer with some hundredth meter of size Earth rotation rate.
First demonstration of laser gyroscopes based on Sagnac effect was published yet in 1963. This was the beginning of a strong technological effort. Since a ring laser gyroscope has no moving mechanical part and, differently from mechanical gyroscopes, is in principles completely not sensitive to translational motion. It was then the ideal solution for inertial navigation.
Starting with the last years of 20th century, thanks to the great improvement in mirror manufactory, was possible building large frame ring lasers with very high sensitivity, paving the way to application in geodesy, in seismology, and more generally in Earth Sciences.
Very sensitive rotation sensors can measure the fundamental geodetic parameters of the Earth rotation (polar motion and length of the day) giving information on the correlation between the Earth centered and the Cosmic inertial reference systems that integrates the Very Large Baseline Interferometry and Global Navigation Satellite System data.
In seismology translation and strain are routinely observed by inertial seismometer and by strain meters. However a full description of the ground movements requires also the acquisition of a third type of measurement, namely rotations. Co-located translation and rotation observables at different sites allow the investigation of the local underground velocity structure.
The lecture will review the present state of the art of large frame ring laser gyroscopes. It will be presented also the new portable instrumentation, based on the passive interferometric fiber optic gyroscope (IFOG), that has been in the recent years introduced for seismological applications.
The research activities of prof. Nicolò Beverini extend to the fields of experimental Atomic Laser Spectroscopy and Frequency Measurements, and to the application of Laser technologies to frequency standards, to geophysical instrumentation, and to fibre optical sensors. He was unit manager and/or principal investigator in many National or European projects.
Between his more important scientific achievements there is the first demonstration in the world of laser cooling in earth-alkali atoms. Important results were also obtained in the field of microwave frequency standards, in strict collaboration with the Italian Institute of Metrology in Turin. It is also worthy of citation the cooperation with the Institute of Laser of RAS in Novosibirsk has brought to the first realization in Italy of a fs laser for generating a frequency comb at the beginning of 2000’s. Relevant is his active in the field of applied physics (optogalvanic spectroscopy; plasma diagnostic through laser methods; optical fiber laser sensors, as marine hydrophones or as stress sensors; instrumentation for geophysics, like atomic magnetometer and gravity gradiometers). Prof. Nicolò Beverini is presently retired, but he is yet involved with the National Institute of Nuclear Physics (INFN) for developing arrays of ring laser gyroscopes with a very large sensitivity to geodetic applications and to fundamental physics tests. He is also charged of the teaching on Instrumentation for Geophysics at the MSc in Applied and Exploration Geophysics of the University of Pisa.
|Prof. Ekkehard Peik is head of the Time and Frequency Department at PTB, Germany’s national metrology institute in Braunschweig.
LECTURE: “Exciting nuclei with lasers”.
Under most circumstances, the energy scales of nuclear and electronic excitations in atoms are separated by 4-6 orders of magnitude. There is one notable exception [1,2]: The low-energy nuclear isomer of Th-229 at an excitation energy of about 8 eV.
The prospect of driving the low-energy nuclear gamma-ray transition between the ground state and this isomer in Th-229 coherently with laser radiation has stimulated numerous innovative ideas and proposals. The selection of a suitable electronic state for the nuclear excitation makes the nuclear transition frequency insensitive against ﬁeld-induced systematic frequency shifts to a degree that is not obtainable in electronic transitions. A nuclear clock  based on laser-cooled and trapped thorium ions will benefit from this advantage. Complementary, the obtainable isolation of the nucleus in a wide-bandgap dielectric creates the opportunity to interrogate many Th-229 nuclei as dopants in a solid, in a laser-driven Mössbauer spectroscopy. While a precise value for the Th-229 nuclear transition energy and an experimental demonstration of resonant optical excitation are still missing, experiments with Th-229 recoil ions from the alpha decay of U-233 have recently provided information on fundamental nuclear properties of the isomer.
-  S. Matinyan, Lasers as a bridge between atomic and nuclear physics, Phys. Rep. 298, 199 (1998)
-  E. V. Tkalya, Properties of the optical transition in the 229Th nucleus, Physics Uspekhi 46, 315 (2003)
-  E. Peik, M. Okhapkin, Nuclear clocks based on resonant excitation of gamma-transitions, C. R. Phys. 16, 516 (2015); also at: arXiv:1502.07322
He studied physics in Göttingen and Munich, obtaining the diploma with a thesis on the observation of Coulomb crystals of laser cooled ions and the PhD with work on laser spectroscopy and laser cooling of In+. He did postdoctoral work on laser cooling of atoms as a Marie-Curie-Fellow at Ecole Normale Supérieure in Paris. Back in Munich, his work continued at the Max-Planck-Institute for Quantum Optics towards an In+ optical frequency standard, including early measurements with a frequency comb. He joined PTB as a scientist in the time unit laboratory in 2001, became head of the working group optical clocks in 2003 and head of the Time and Frequency Department in 2007. He is also Privatdozent at the Physics Department of Leibniz University Hannover. His scientific interests are: laser cooling and trapping of atoms and ions, laser spectroscopy, the metrology of time and frequency, tests of fundamental principles with atomic clocks, and nuclear physics with lasers, inspired by the prospect to build an optical nuclear clock based on Th-229.
Prof. Arakelian Sergei Martirosovich – Senior Doctor of Physics-Mathematical Sciences, Chairman of the Department of Physics and Applied Mathematics – Vladimir State University, Vladimir, Russia.
LECTURE: “New dimensional cluster physics for the laser-induced topological nanostructure thin films on solid surface: basic principles and possible applications”.
I will discuss in both theory and experiment the laser-induced nanocluster structures of different types (in topology and element composition) taking into account the correlations in nanoparticle ensemble by quantum states. The problem of high temperature superconductivity due to topological surface structures with correlated states (resulting in coupled states on new dimensional principles) is under consideration.
Several applied laser procedures to obtain the nanostructures and thin films with controllable topology are under consideration. Namely in addition to the direct laser modification of solid surfaces, we used, first, the laser ablation of targets in liquid to obtain colloidal systems and, second, to deposit the nanoparticles from the colloid on a solid surface for formation of nanostructures in necessary way by two technique: the laser radiation action and the droplets falling from the nozzle.
In experiment, there is a competition between increase conductivity while opening new channels in a spatially inhomogeneous charged structure and increase the resistance by increasing of the areas between the conductive grains. Such electrical transport properties (due to quantum correlated states resulting in tunnel and hopping electroconductivity) may be presented as a special type of topological electrophysical surface structures (both localized and delocalized coupled states for charge carriers). Dramatic enhancement of electroconductivity (in several orders) has been observed in our experiments due to variation of topological peculiarities of a nanocluster thin film system.
As to optical properties of bimetallic (Ag+Au) films we demonstrated that it is possible to control both the plasmon resonance behavior and propagating plasmon waves due to inhomogeneous structure (being a random manifestation of special schemes for travelling waves). Absence of narrow plasmon resonance is namely due to inhomogeneous nanostructure. In addition, we observed in our experiments the formation of the artificial meso-atom nanostructures when positive nucleus being the Si-atom (electrically positive due to surface breaking of chemical bonds under non-radiative recombination of optically generated free carriers) are covered by negative charged Au-atoms (indicated by Z-potential measurements). Such objects may be presented as a shell-like dot structure, and the modelling of the unusual structures has been carried out by us for different conditions.
The linear chains of a carbon structure (carbyne) have been studied as well in respect of both electrical and optical properties.
Obtained results give us an opportunity to establish the basis of new physical principles to create the functional elements for optoelectronics and photonics in hybrid set-up (optics + electrophysics) by the different topology controllable nanoclusters with dramatic increase of both electroconductivity and optical response vs spatial structure of nanoclusters in thin films at room temperature.
Prof. Arakelian S.M. is considered to be a noted expert in the area of laser/quantum optics, coherent and non-linear optics as well as in the field of quantum information systems and quantum computing not only in our country but also abroad. He is the author of more than 300 profound scientific papers published in refereed scientific journals and patents.
In 1966 he graduated with silver medal from high school № 239 on physics and mathematics in Leningrad, and entered the Polytechnic Institute in Leningrad. Prof. Arakelian graduated with honors from Yerevan State University in 1971 (Department of Optics at Faculty of Physics). A.S.M. was working at his diploma project at the Department of General Physics and Wave Processes of the Faculty of Physics at the Lomonosov Moscow State University (MSU). Later he took graduate courses at this University (1971-1974), and in 1975 he has got his candidate (PhD) thesis in Physics and Mathematics (scientific interests – statistical and coherent/nonlinear optics). In 1988 A.S.M. has got his Senior Doctor of Science/thesis in Physics and Mathematics (non-linear spectroscopy and laser physics) at the MSU as well. Since 1988 he is a Professor of the Department of Optics, and since 1990 – the Chairman of the Department of Molecular Physics and Laser Biophysics of the Faculty of Physics at Yerevan State University (Armenia). Since 1992 – Professor of the Department of Physics and Applied Mathematics and since 1994 to a present time A.S.M. is the Chairman of the above Department at Vladimir State University (VlSU) – the city of Vladimir, Russia. From 1996 to 2003 A.S.M. was working as a vice-rector in Informatics and Information Technologies at VlSU. For the period of 2003-2005 he was a Deputy Director on young scientists and student activity at the State Scientific Center «Astrophysics» of Russian Federation (Moscow) associated with Dept. of Physics of National Research University MIPT (Moscow Institute of Physics and Technology). Since 2006 to 2012 A.S.M. has been a vice-rector in Innovations and Strategic Development at VlSU.
In 1995 A.S.M. was elected an active member of the Russian Academy of Engineering Sciences.
Having the status of a Post-Doctor A.S.M. stayed at Faculty of Physics at the University of California (UCB), the city of Berkeley (USA) in 1980-1981. He also worked at UCB as a Visiting Professor in 1985. In 1981 A.S.M. became a member of the American Optical Society.
|Prof. Gerd Leuchs – Max Planck Institute for the Science of Light, Erlangen-Nuremberg, Germany, scientific member of the Max Planck Society, Member of the Academy of Sciences Leopoldina and the Russian Academy of Sciences, German Physical Society, European Physical Society, German Society of Applied Optics, Optical Society of America, and the American Association for the Advancement of Science.
LECTURE: “Calculating Correlation Functions from Phase Space Distributions”.
The state of a light field can be either characterized by the correlation functions as introduced by Glauber (1963) or by the corresponding distribution in phase space. Phase space is spanned by conjugate variables, which do not commute in quantum optics. As a result there are different types of phase space distribution functions, such as the Wigner function and the Husimi function (or equivalently Q-function). These different types are related to different orderings of the field operators. In practice the Wigner function is obtained by tomographic reconstruction from date obtained with 4-port homodyning (Smithey, Beck, Raymer and Faridani 1993), while the Q-function can be measured directly using 8-port homodyning. Alternatively the field can be characterized by coincidence measurements yielding various correlation functions, such as the famous intensity correlation function first used by Hanbury-Brown and Twiss (1956). In the lecture I will describe how the correlation function can be calculated from the moments of the phase space distributions.
Gerd Leuchs studied physics at the University of Cologne and holds a Ph.D. degree from the University of Munich. His PhD-thesis deals with the fine structure splitting of sodium Rydberg atoms. He received the Habilitation degree at the University of Munich on multiphoton processes in atoms. Gerd Leuchs is a full professor of physics at the Institute of Optics, Information and Photonics of the University Erlangen-Nuremberg. Since 2009 he is director at the Max Planck Institute for the Science of Light and since 2011 he is professor adjunct at the University of Ottawa. He is member of the German Academy of Sciences Leopoldina and of the Russian Academy of Sciences. He holds an honorary doctoral degree from the Danish Technical University and a honorary professorship of St. Petersburg State University. He won the 2005 Quantum Electronics and Optics Prize of the European Physical Society and 2017 the Julius von Haast Fellowship Award by the Royal Academy of New Zealand. In 2012 he obtained the Cross of Merit of the Federal Republic of Germany and 2018 the Herbert Walther prize awarded jointly by the Optical Society (OSA) and the Deutsche Physikalische Gesellschaft. Actually he is working on a Mega-Grant of the Ministry of Science and Education of the Russian Federation. Gerd Leuchs is a worldwide honoured top researcher and his research spans the whole range from classical to quantum optics.
|Igor Ryabtsev – Rzhanov Institute of Semiconductor Physics SB RAS, Russia, Corresponding
Member of RAS, member of the Board of Atomic, Molecular and Optical Physics Division (AMOPD) of the European Physical Society (EPS)
LECTURE: “Quantum information with single atoms and photons”.
In this lecture, we will give an overview of the current status of quantum information processing with single atoms and photons. We will also present our related experimental and theoretical results on long-range interactions in mesoscopic ensembles of cold Rydberg atoms [1,2] and on quantum key distribution with single photons .
One of the promising approaches to build a quantum computer is the usage of single neutral atoms as quantum bits (qubits) [1,2]. Such atoms, being trapped by laser radiation to optical lattices or dipole trap arrays with the period of a few microns and cooled down to the temperatures below 100 µK, represent a quantum register of qubits for a quantum computer. Quantum algorithms should performed as a sequence of one- and two-qubit gates. Single-qubit gates are realized using Raman transitions in a bichromatic laser field or microwave transitions between hyperfine sublevels of the ground state. More complicated two-qubit gates, which make the two qubits entangled, are implemented by temporary laser excitation of the atoms to highly excited Rydberg states exhibiting strong long-range interactions. Rydberg atoms can also be used for deterministic loading of single atoms to the sites of the quantum register. The work in this direction is intensively carried out worldwide and in our group.
Another research field is quantum communications with single photons propagating over a quantum channel – free space or optical fiber . Such communications can provide absolute security due to the lows of quantum mechanics, which prohibit precise measurements of the states of single photons at their unsanctioned interception. We have developed two experimental setups for quantum key distribution in the atmospheric and fiber-optic quantum channels and performed the experiments on single-photon data transmission. The work on improving the communication rate and data security is in progress.
This work was supported by the RFBR Grants No. 16-02-00383 and 17-02-00987, the Russian Science Foundation Grants No. 16-12-00028 (for laser excitation of Rydberg states) and 18-12-00313 (for theoretical analysis), the Siberian Branch of RAS, and the Novosibirsk State University.
-  I.I.Ryabtsev et al., Physics − Uspekhi 59, 196 (2016).
-  I.I.Ryabtsev et al., Russian Microelectronics 46(2), 109 (2017).
-  I.I.Ryabtsev et al., Russian Microelectronics 46(2), 121 (2017).
Igor I. Ryabtsev graduated from the Physical Department of the Novosibirsk State University in 1986. Since 1983, he participated in the experimental research of Rydberg sodium atoms at the Laboratory of Nonlinear Resonant Processes and Laser Diagnostics as a student, and then as an intern-researcher. In 1992 he defended his Ph.D. thesis “IR and microwave spectroscopy of resonant and multiphoton transitions in Rydberg atoms of sodium”. In 2000 he was appointed as a head of the laboratory and works in this position up to the present. In 2005 he defended his doctoral dissertation “Spectroscopy of coherent and nonlinear processes in Rydberg atoms.”
At present days, the main subject of scientific research of I.I.Ryabtsev is a new direction of quantum physics – quantum information. In the laboratory of I.I.Ryabtsev, the first experimental setup in Russia was created for the laser and microwave spectroscopy of cold Rb Rydberg atoms in a magneto-optical trap, and experimental and theoretical studies related to quantum information processing with Rydberg atoms are being performed. Another direction of I.I.Ryabtsev scientific research is experimental quantum cryptography and quantum key distribution with single photons in the free space at distances of up to 10 km and in fiber-optics telecommunication lines at distances up to 100 km.
|Prof. Sergei Kulik Head of Quantum Optical Technology Lab, Scientific Leader of Quantum Technology Centre, Doctor of Sciences (Phys. & Math.).
LECTURE: Quantum Interference: Spectroscopy Applications.
Spectral measurements in the infrared (IR) optical range provide unique fingerprints of materials which are useful for material analysis, environmental sensing, and health diagnostics. Current IR spectroscopy techniques require the use of optical equipment suited for operation in the IR range, which faces challenges of inferior performance and high cost. Here we develop a spectroscopy technique, which allows spectral measurements in the IR range using visible spectral range components. The technique is based on quantum interference of infrared and visible photons, produced via Spontaneous Parametric Down Conversion (SPDC). The intensity interference pattern for a visible photon depends on the phase of an IR photon, which travels through the media. This allows determining absorption coefficient and refractive index of the media in the IR range from the measurements of visible photons. The technique can substitute and/or complement conventional IR spectroscopy and refractometry techniques, as it uses well-developed optical components for the visible range.
From 1986 to 1994 Sergei Kulik major work was experimental studying of the statistical properties of scattered light fields. This, in particular, includes the variation of the scattered light statistics which results from the increase of Raman frequency shift. The limit case is a quasi-elastic scattering by chaotic small particles with sizes of the same order as the light wavelength. At present, an analogous problem is being solved for the case of scattering by acoustic waves propagating in a crystal, so that their correlation properties are pre-determined by hand.
Another branch of Sergei Kulik activity covers the problem of biphoton interference (1997-). His group consider the field interference of the second- and the fourth order in different interferometric schemes for spontaneous parametric down-conversion. Also was developed the effective interferometric protocols to generate some specific quantum states of light (the Bell states) in the most common case: broad spectrum of the pump (in particular for the femtosecond laser), any type of phase-matching (either type-I or type-II), and arbitrary length of nonlinear crystals.
We implemented a quantum teleportation protocol in which nonlinear interactions were used for Bell state measurement (2000). The distinct feature of this experiment is that all four Bell states can be distinguished in the Bell state measurement.
The preparation, transformation and measurement of the given biphoton polarization states in single spatial mode is the main objective during last years (2000-).
At the present time his group develop the concept of quantum trits or qutrits and quantum quarts or ququarts. Was demonstrated that these objects can be realized using polarization tates of frequency degenerate collinear biphoton field. Coherent superposition of three (four) orthogonal basic biphoton states emitted from three (four) nonlinear crystals implements photonic three-state (four-state) system.
There are four main branches of his scientific interest:
- spectroscopy of spatially inhomogeneous solid structures,
- investigation of the statistical properties of scattered light fields,
- quantum optics – different types of the light interference,
- quantum information and quantum communications.
|Hélène Perrin – Université Paris 13, Villetaneuse, France, member of the scientific board of the (National) Physics Institute of CNRS, member of steering committees in France : SIRTEQ network on Quantum Technologies, Cold Atoms French network
LECTURE: Adiabatic potentials for radio-frequency dressed atoms
Manipulating atoms with fields is at the heart of modern AMO physics. In particular, cold atoms and quantum gases present low enough energies for being confined in potentials created by laser beams or magnetic fields. To these popular traps, we can add another more recent method which bring new possibilities for unusual geometries, far from the simple harmonic trap. Adding a radio-frequency (rf) field to an inhomogeneous magnetic field enables the creation of trapping potentials relying on the adiabatic following of a dressed state.
In the lecture, I will describe the principle of rf-dressed adiabatic potentials, explicit a few trapping configurations (double-well, `bubble trap’, ring trap) and show recent applications to cold atom experiments.
- 2017-: CNRS Research Director
- 2012- : Group leader of BEC group at LPL
- 2002 : CNRS senior researcher
- 1999: CNRS junior researcher
- 1998-1999: Post-doc at CEA/SPEC with Ch. Glattli on noise measurements in two-dimensional electron gases
Research topics: experimental and theoretical atomic physics. Laser cooling, Bose-Einstein condensation, low dimensional quantum gases, superfluidity
|Martial Ducloy – Laboratoire de Physique des Lasers, Université Paris 13, Division of Physics and Applied Physics, NTU, Singapore, Foreign Member of Academia Europaea, the Russian Academy of Sciences, & the Bulgarian Academy of Sciences
LECTURE: Doppler-free monitoring of electric quadrupole transitions in atomic vapours.
Doppler-free spectroscopy has been demonstrated and, in general, exploited using electric dipole atomic or molecular transitions (E1). In this lecture I will consider the extension of these methods to dipole-forbidden transitions e.g. electric quadrupole transitions (E2). Both three-level spectroscopy in atomic vapours  and Selective Reflection of light at various interfaces will be considered.
 E. A. Chan et al, Optics Letters 41, 2005 (2016)
M. Ducloy’ research interests are centred on basic processes of laser-matter interactions, and their applications in laser spectroscopy and metrology, nonlinear and quantum optics, laser control of atom motion and matter-wave optics, cavity QED processes and nano-optics.
After a thesis work on optical pumping with lasers, he turned to the analysis of resonant nonlinear optics and four wave mixing processes in dilute vapours or gases.
Among many works performed: the study of basic processes involved in saturated phase-conjugation and the demonstration of dominant dispersive character of the atomic response (1982); the demonstration of very large efficiency (>100%) in phase-conjugate reflectors, leading to self-induced phase-conjugate oscillation in atomic vapours and opening the way to a new class of nonlinear unstable and chaotic behaviours using DFWM processes in resonant media; prediction and demonstration of optical phase conjugation with frequency doubling, via higher-order non degenerate multi-wave mixing.
M. Ducloy pioneered the use of DFWMP to devise high-frequency shot-noise-limited optical heterodyne laser spectroscopy. Among many developments (frequency stabilisation and metrology…), a major one has been in high-resolution atomic spectroscopy at gas-solid interfaces -nonlinear spectroscopy and saturated absorption with evanescent waves-, and later in Doppler-free reflection spectroscopy – work which is the starting point to a series of studies developing a laser-spectroscopy approach to atom-surface interactions and cavity QED experiments. The key work has been a case of textbook experiment, demonstrating the van der Waals (vW) long-range attraction between atom and surface, and based on spectral monitoring of the surface-induced red-shift of the atomic response, in straight reflection spectroscopy at normal incidence on a dielectric-vapour interface (1991). Many works followed in this cavity QED field, analysing all the properties of atom-surface interaction (e.g., atom adsorption-desorption dynamics, surface re-distribution of gas atom velocities, etc). This culminated (1999) with the surprising demonstration that the basic vW attraction between neutral bodies can be turned into a long range vW repulsion, when the internal dynamics of the polarisable systems allows for a resonant virtual energy coupling between the two bodies (experiments on Cs/sapphire) – followed by demonstrations of long-range dissipative coupling (of the FRET type) between surface-polaritons and atomic systems. Recent works include spectroscopy/dynamics of gas atoms in nanometre vapour cell – with the first demonstration of coherent Dicke narrowing in the optical range, the exploration of vW forces in an unexplored distance range (20-100nm). The symmetry breaking character of atom-surface interactions was shown in surface/metastable beam collisions, where the anisotropic (quadrupolar) part of the vW interaction produces an exo-energetic metastability transfer between two different metastable states of rare gases. Extension to vW-induced transitions between Zeeman sublevels has opened the way to novel angle-tuneable atomic beam splitters and new approaches in matter wave interferometry (Fresnel atom interferometer, Schlieren-type atom nanoscope). This work extends now to atom-nanobody interactions and hybrid optical systems. Other recent interests are in matter-wave optics (as compared to light optics): non-diffracting atom nano-waves (similar to Fresnel beams in optics), negative-index media for atom optics and their applications.