School on Interaction of Light with Cold Atoms

January 30 – February 10, 2017

São Paulo, Brazil

ICTP-SAIFR/IFT-UNESP

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Light-matter interaction is one of the oldest, broadest and most fundamental scientific topics. Progress made during the last three decades in the preparation of cold matter and the suppression of classical noise allowed the emergence and the experimental manipulation of special coherence properties of matter and light, with applications to quantum sensing and quantum information processing.

This school is for students and young researchers interested in fields related to light scattering, cold and ultra-cold matter, quantum information and quantum optics. Participants will be invited to give short talks and present posters on their research activities. There is no registration fee and limited funds are available for travel and local expenses.

This activity will be followed by the ‘Experimental Week of Atomic Optics (February 13-17, 2017)’ to be held at USP-São Carlos (IFSC-USP). The students interested in participating in this experimental event should send an email to week.atomic.optics@gmail.com. Limited funds for travel (São Paulo – São Carlos) and local expenses will be provided by CePOF – Centro de Pequisas de Ótica e Fotônica.

Organizers:

  • Romain P. M. Bachelard (IFSC-USP, Brazil )
  • Philippe W. Courteille (IFSC-USP, Brazil )
  • Robin Kaiser (Institut Non Linéaire de Nice, France)
  • Rodrigo F. Shiozaki (IFSC-USP & UFSCar, Brazil)
  • Raul C. Teixeira (IFSC-USP & UFSCar, Brazil)

Satisfaction survey:

Lecturers and Speakers

Lecturers:

First week

Photons and Atoms
Jean-Michel Raimond (Université Pierre & Marie Curie, France)
This lecture series will provide an introduction to the interaction of quantum fields with atoms. We will outline the field quantization procedure. We will describe a few interesting single-mode field quantum states (Fock states, coherent states, squeezed and cat states). We will introduce phase space representations, including the Wigner function. We will examine simple optical operations, such as those performed by beamsplitters on classical and non-classical states. We will give a rapid treatment of single-mode field relaxation. We will then switch to the interaction of a quantum single-mode field with atoms and introduce the Jaynes Cummings Hamiltonian and the dressed states picture. We will illustrate these important tools with simple situations in Cavity- and Circuit-quantum electrodynamics.

Bibiliography:
• R. Loudon, Quantum theory of light, OUP 1983
• C. Cohen-Tannoudji, J. Dupont-Roc and G. Grynberg, An introduction to quantum electrodynamics and Photons and atoms, Wiley, 1992
• C. Cohen-Tannoudji and D. Guery-Odelin Advances in atomic physics: an overview, World Scientific 2012
• S. Barnett and P.M. Radmore, Methods in theoretical quantum optics, OUP, 1997
• S. Haroche and J.M. Raimond, Exploring the quantum, OUP 2006

Quantum gases 
Jook Walraven (Universiteit van Amsterdam, Netherlands)
In this course an introduction will be given in the physics of quantum gases. The starting point is the quantum mechanics of many-body quantum systems, the quantum statistics and the importance of second quantization. We discuss the difference between Bose and Fermi gases. We introduce quantum fields and introduce the concept of the order parameter. This leads to the derivation of the Gross-Pitaevskii equation and the Bogoliubov excitation spectrum as well as the Landau criterion for superfluidity. The material of the course is written up in syllabus of lecture notes.

Ultracold atoms in optical lattices
Christof Weitenberg (Universität Hamburg, Germany)
In recent years, ultracold atoms have established as a fruitful tunable platform to study a variety of many-body effects. In particular, the addition of optical lattices allows to investigate interesting solid state physics such as the Mott insulator transition of quantum magnetism within the Hubbard model. New developments enrich the possibilities to taking snapshots of the correlations in a quantum gas microscope and to the study of non-cubic lattices and non-trivial topology. In this lecture series I will introduce the basic tools and models to describe these systems and the most important experimental measurement techniques that are used in current research.

 

Second week

Quantum information with photons
Luiz Davidovich (Universidade Federal do Rio de Janeiro, Brazil)

Cold Rydberg systems
James P. Shaffer (University of Oklahoma, USA)
Recently, there have been a string of exciting discoveries emerging from the study of highly excited Rydberg atoms resulting in an explosion of activity in Rydberg atom physics, particularly at ultracold temperatures. Advances in both fundamental and applied areas of research have been made. These include quantum information with Rydberg atoms, Rydberg atom interactions in general, quantum optics with Rydberg atoms, the formation of novel types of molecules and RF electric field-sensing. These areas of research are a few of the most notable examples of the uses for Rydberg atoms that have garnered significant interest in the last several years, leading to a renaissance in the field. Many of these results stem from the long range interactions between Rydberg atoms that can be controlled by state selection and electric and magnetic fields. For example, interactions between ultracold Rydberg atoms can enable the quantum entanglement of large numbers of atoms. Quantum entanglement of material particles is extremely difficult to do and the Rydberg atom system provides this opportunity at relatively low cost by using the interactions between the atoms to split the excitation states of a collection of atoms. Quantum entanglement is important for a variety of novel devices that cannot be constructed without it. In this series of lectures we will give an introduction to Rydberg atom interactions. Then, we will describe the study of novel types of Rydberg atom molecules. Finally, we will show how Rydberg atoms can be used for absolute RF electric field sensing. These topics will provide students with an overview of the field.

Cold molecules & Efimov physics
Claus Zimmermann (Universität Tübingen, Germany)
Cold atomic gases consist of well understood microscopic quantum objects which move very slowly.  At such low collisional energies almost all specific properties of the individual atoms smear out, leaving the scattering length as only specific parameter for binary interaction. This parameter can even be tuned over a wide range by applying a variable magnetic field. Since all systems with equal scattering length behave essentially the same one obtains a universal playground for few body quantum physics at low temperature.
In the first lecture we will discuss the qualitative physical picture of halo states, feshbach molecules, and efimov trimeres. The next two lectures provide details, including heteronuclear systems with large mass difference, scaling behavior of Efimov trimers, and experimental examples.

Speakers:

  • Vanderlei S. Bagnato (IFSC-USP, Brazil): Quantum turbulence 

In this sequence of lectures we shall present the basis and discuss the possibilities for research in the field of turbulence in BEC. The investigation of QT in BEC create new and exciting possibilities that go beyond the comparison with classical turbulence. With trapped superfluids, turbulence is unique for investigation in 2D or 3D. Using the point of view of matter wave, a turbulent cloud of atomic superfluid present properties that are equivalent to a propagating speckle field of light. Turbulence for a BEC is what speckle is for a Gaussian coherent beam of light. In this presentation we shall discuss an overview of experiments in our laboratory as well as the recent quantification of disorder in a QT BEC, correlations and comparison with speckle field as well as possible thermodynamic characterization of this non-equilibrium state. The possibility for spontaneous generation of turbulence in droplets of condensate will be presented and the present experimental status of it discussed. Special printed material and a collection of fundamental publications will be provided for the participants.

  • Philippe W. Courteille (IFSC-USP, Brazil):  Atom-cavity interactions in the service of inertial sensing 

Cold atomic clouds interacting with a laser-pumped optical cavity can develop macroscopic instabilities triggered by correlations between subsequent scattering processes. Indeed, a signature (or coherence) imprinted into a cloud by a first photon influences the scattering of subsequent photons, which eventually amplify the coherence and thus generate instabilities. We will show, how a control of the gain mechanism by external periodic potentials can self-synchronize the evolution of matter waves, and how it may be harnessed for in vivo monitoring of matter wave trajectories and inertial sensing.

  • Alejandra Valencia (Univ. de los Andes, Colombia): Experimental quantum optics: a testbed for quantum measurement  and quantum decoherence

Photonic setups have been demonstrated to be excellent tools to simulate and test the predictions given by quantum mechanics. In general, photons can be described by considering its different degrees of freedom, polarization, frequency, and spatial variables that may include transverse momentum and orbital angular momentum. In this talk, I will describe our research on the experimental control of the transverse momentum variable of light  as well as its coupling with polarization to study topics such as open quantum systems and measurement theory.  In particular, our photonic systems of interest are heralded single photons and paired photons generated via the non-linear process of spontaneous parametric down conversion (SPDC).

  • Emanuel A.L. Henn (IFSC-USP, Brazil): Ultracold Dipolar Gases

In this lecture I will review the fundamental aspects of the physics of ultracold dipolar gases. We will go through the basic theoretical results, early experimental findings and modern breakthroughs with the successful cooling of highly magnetic lanthanide atoms.

  • Aldo P. Delgado Hidalgo (Univ. de Concepción, Chile): Quantum tomography 
  • Robin Kaiser (INLN – Nice, France): Coherence and diffusion in light-matter interaction

The quest for Anderson localization of light is at the center of many experimental and theoretical activities. Cold atoms have emerged as interesting quantum system to study coherent transport properties of light. Initial experiments have established that dilute samples with large optical thickness allow studying weak localization of light.
The goal of our research is to study coherent transport of photons in cold atomic samples. One important aspect is the quest of Anderson localization of light with cold atoms and its relation to Dicke super- or subradiance.
In this lecture I will review experimental and theoretical state of the art on the possibility of Anderson localization of light by cold atoms.

  •  Tommaso Macri (IIP-UFRN, Brazil): Quantum simulation with Rydberg atoms and dipolar systems

The realization and the control of long range interactions with atomic systems at very low temperatures opens up a whole new realm of many-body physics that has become a central focus of research. In the first part I will show from a theoretical perspective how non-local Ising interactions in optical lattices can provide an optimal playground for the engineering of exotic crystalline phases that has been recently realized in the lab. In the second part I will focus on the quantum phases of dipolar bosons at zero and finite temperature. I will discuss the superfluid properties of such phases investigated via Path intergral Monte Carlo methods and the possibility of observing them in the laboratory.

  • José W. R. Tabosa (UFPE, Brazil): Nonlinear optics with cold atoms

In this lecture I will present an overview on the nonlinear interaction of light with an ensemble of laser-cooled atoms. Some of the phenomena to be discussed include electromagnetically induced transparency (EIT), coherent population oscillations (CPO) and multi-wave mixing (MWM) processes. Applications of these nonlinear optical phenomena for the storage and manipulation of light will also be presented. In particular, I will specially consider the case where the interacting light fields carry orbital angular momentum (OAM).

Poster

Program

School Program: PDF version (updated on February 2, 2017)

 

1st week
30/01/17 31/01/17 01/02/17 02/02/17 03/02/17
Monday Tuesday Wednesday Thursday Friday
09:00 – 10:30 Registration and Opening (30′) CW-1 (video) (PDF) CW-3 (video) (PDF) JW-2 (video) (PDF) LD-3 (video) (PDF)
10:30 – 11:00 COFFEE BREAK
11:00 – 12:30 JMR-1 (video) (PDF) JMR-3 (video) (PDF2) JMR-4 (video) ADH (video) (PDF) LD-4 (video) (ex)
12:30 – 14:00 Lunch Lunch Lunch Lunch Lunch
14:00 – 15:30 JW-1(video) (PDF) CW-2 (video) (PDF) LD-1 (video) (PDF) LD-2 (video)  JW-3 (video) (PDF)
15:30 – 16:00 COFFEE BREAK
16:00 – 17:30 JMR-2 (video) Posters I CW-4 (ex) JMR-5 (ex) (video) JW-4 (video) (PDF)
17:30 – 19:00 Exercise session JMR: APS Exercise session
2nd week
06/02/17 07/02/17 08/02/17 09/02/17 10/02/17
Monday Tuesday Wednesday Thursday Friday
09:00 – 10:30 JPS-1 (video) (PDF) JPS-2 (video) (PDF) VB (video) (PDF) TM (video) (PDF) PC (video) (PDF)
10:30 – 11:00 COFFEE BREAK
11:00 – 12:30 CZ-1 (video) AVG (video) (PDF) JPS-3 (video) (PDF) CZ-3 (video) EH (video) (PDF)
12:30 – 14:00 Lunch Lunch Lunch Lunch Lunch
14:00 – 15:30 JW-5 (video) (PDF) CZ-2 (video) JWT (video) (PDF) RK (video) (PDF) Closing (30′)
15:30 – 16:00 COFFEE BREAK
16:00 – 17:30 Discussions JW-6 (ex) (video) Student presentations Posters II
17:30 – 19:00 Exercise session
Long courses
JMR – Photons and Atoms (Jean-Michel Raimond) – 4 lectures + 1 exercise section
JW – Quantum Gases (Jook Walraven) – 4 lectures + 1 exercise section
CW – Optical lattices (Christof Weitenberg) – 3 lectures+ 1 exercise section
LD – Q. Information with Photons (Luiz Davidovitch) – 3 lectures + 1 ex. section
JPS – Cold Rydberg systems (James P. Shaffer) – 3 lectures
CZ – Cold molecules and Efimov physics (Claus Zimmermann) – 3 lectures
(ex) – exercises section
Short courses
JMR:APS – Edition and reviewing process at the APS (Jean-Michel Raimond)
PC – Atom-cavity interactions in the service of inertial sensing (Philippe Courteille)
RK – Coherence and Diffusion in Light-Matter Interaction (Robin Kaiser)
ADH – Quantum Tomography (Aldo Delgado Hidalgo)
VB – Quantum Turbulence (Vanderlei Bagnato)
EH – Ultracold Dipolar Gases (Emanuel Henn)
AVG – Experimental quantum optics: a testbed for quantum measurement and quantum decoherence (Alejandra Valencia Gonzalez)
JWT – Nonlinear optics with cold atoms (José W. Tabosa)
TM – Quantum simulation with Rydberg atoms and dipolar systems (Tommaso Macri)
Discussions/preparation of exercises

Student Presentations

Exercises

Jean-Michel Ramond

Jook Walraven

Christof Weitenberg

Photos

School on Interaction of Light with Cold Atoms

Additional Information

List of Confirmed Participants: Updated on January 20

Poster presentation: Participants who are presenting a poster MUST BRING THE POSTER PRINTED. The poster size should be at most 1,5m x 1m.

Registration: ALL participants should register. The registration will be on January 30 at the institute from 9:00 to 10:00 am. You can find arrival instructions at http://www.ictp-saifr.org/?page_id=195

Accommodation: Participants, whose accommodation has been provided by the institute will stay at The Universe Flat. Each participant, whose accommodation has been provided by the institute, has received the accommodation details individually by email.

BOARDING PASS: All participants, whose travel has been provided or will be reimbursed by the institute, should bring the boarding pass upon registration, and collect an envelope to send the return boarding pass to the institute.

Emergency number: 9 8233 8671 (from São Paulo city); +55 11 9 8233 8671 (from abroad), 11 9 8233 8671 (from outside São Paulo).

Ground transportation instructions: 

Ground transportation from Guarulhos Airport to The Universe Flat

Ground transportation from Congonhas Airport to the Universe Flat

Ground transportation from The Universe Flat to the institute