1. Atom Chips and Photonic Crystals
Chiara Fort
Francesco Cataliotti
Diederik Wiersma
Francesco Marin

2. Ultracold Atoms and Optical Lattices
Traditional Systems
Current ~ 100 A
Power ~ 1.5 kW
n = Hz +
Ultra High Vacuum ~ Torr
double MOT system:
Laser power ~ 500 mW
Large BEC 106 atoms
but
production cycle > 1 min
Well established experimental procedure, possibility of working with large atomic samples, very well proven versatility
Low repetition rate, complicated and expensive, single site access problematic

3. Atom Chips and Photonic Crystals
Novel Technology
Micro-chip traps
Photonic Crystals +
Silicon: 2 cm x 3 cm x 600 mm Gold microwires: 2.5 mm X 50 ~ 300 mm Currents: < 2 A
single MOT system:
Laser power ~ 100 mW
Fast and cheap experiments, extreme versatility, possibility of single site addressing, cross fertilization from different active fields
“Small” atomic samples, Mixtures yet to be proven, New technologies involved

4. Outlook Cooling and trapping Atoms on a Microchip Photonic materials
Photonic BEC?
Conclusions

5. Degenerate Atoms (road to work)
1925: Einstein predicts “condensation” of bosons
60’s: Development of Lasers
80’s: Development of laser cooling
1985: Magnetic Trapping of ultracold atoms
1986: Optical trapping of Na
1987: Na Magneto-Optical Trap
1995: First 87Rb Bose-Einstein Condensate
Huge playground for fundamental physics:
BEC with Li, Na, K, Cs, Fr…
Optical gratings, collective excitations…
First applications:
Interferometry
Earth and Space sensors
Quantum Information
2001: First BEC of 87Rb
on an Atom Chip

6. Loading atoms on a microchip
Ridurre la distanza tra la MOT e il MicroChip. s+ s- s+ s- s+ s-

7. Loading atoms on a microchip

8. Trapping atoms on a Chip
Planar Geometry  gold microstrips on silicon substrates
Bwir (Iwir= 3A)
Bbias =
{0,3.3,1.2} Gauss
|B| (Gauss)
z (mm)
Iwir= 3 A ; Bbias= {0,3.3,1.2} Gauss
Iwir= 1 A ; Bbias= {0,3.3,1.2} Gauss
|B| (Gauss)
x (mm)

9. Trapping atoms on a Chip
Quadrupole trap (B=0 at minimum)
- Good for magneto-optical traps
Ioffe-Pritchard trap (B>0 at minimum)
- Good for magnetic trapping. ΔE
m=1
Magnetically trapped state
m=0
|B|
m=-1

10. Trapping atoms on a Chip

11. Trapping atoms on a Chip
Varying the current on the chip it is possible to manipulate the atoms
Chip realized in AtomInstitut in Vienna.
Assembled at INFN by E. Scarlini, I. Herrera and L. Consolino

12. Trapping atoms on a Chip

13. Photonic Materials
Photonic crystals are periodic optical (nano)structures that are designed to affect the motion of photons in a similar way that periodicity of a semiconductor crystal affects the motion of electrons. Photonic crystals occur in nature and in various forms have been studied by science for the last 100 years.

14. Photonic Materials
Multiple light scattering and optical amplification - Lasing based on trapping of light in random systems - Fundamental physics: Anderson localization of light - Mechanism behind lasing understood, Levy statistics - Applications under development in photonic devices and sensing
Local micro-infiltration of liquids (water) in 2D photonic crystals - New technology to realize photonic circuits - Rewritable and flexible structures (combine sources, switches, waveguides,…) - Locally controlled infiltration with 100 nm accuracy - Based on NSOM, confocal microscopy

15. Photonic Materials Integrated waveguides
Using nanostructured materials it is possible to create photonic structures to realize either planar or linear waveguides. By getting the atoms at micrometric distances from the structured surface we will be able to make them interact with the evanescent wave field leaking out of similar waveguides. We will be able to efficiently address the atoms with different optical wavelengths creating both repulsive and attractive potentials. the ability to use different light colours in the waveguides will also enable us to create a various potential geometries going from purely periodic to quasi periodic with the possibility of generating very well controllable time dependent potentials.

16. Conclusions
The atoms will be brought in the evanescent field of micro and nanostructures
Reproducible potentials for atoms will be realized
Modification of optical properties of structures will be possible
Very small atom-surface distances
Small index of refraction of atomic samples

17. Photonic BEC Mirror mass M ≈ 10-20 Kg Mirror Temperature T = 0 K
When atoms are trapped in the periodic structure formed by an optical lattice, the stystem behaves as a Bragg mirror in its ground state
Mirror mass M ≈ Kg
Mirror Temperature T = 0 K
Reflectivity
Bandwidth
Physical Review Letters 104, (2010)

18. Coherent optical information storage in cold atoms
(with P. Lombardi, F. Marin and E. Giacobino)
C. Liu, Z. Dutton, C. H. Behroozi, L. Hau Nature 409, 490 (2001)

19. Utilizzo personale e strutture
Studenti:
Pietro Lombardi (Dott.)
Francesco Cappelli (LS)
Personale strutturato:
Chiara Fort
Francesco Cataliotti (DE)
Francesco Marin
Massimo Inguscio
Personale non strutturato:
Ivan Herrera (LENS)
Jovana Petrovic (LENS)
Impatto Dipartimento:
Assistenza microsaldatura e micromanipolazione per assemblaggio (1 – 2 settimane x anno) (Enrico Scarlini)

20. Pubblicazioni (dal 2007)
“Magnetic microtraps for quantum control” I. Herrera, G. D’Arrigo, M. Siciliani de Cumis, F. S. Cataliotti International Journal of Quantum Information 5, 23-31 (2007)
“Modeling the dynamics of a weakly coupled chain of quantum systems” F. S. Cataliotti, L. Fallani, F. Ferlaino, C. Fort, P. Maddaloni, M. Inguscio. New Journal of Physics 10th Anniversary Highlights 14 (2008)
“Interferometric quantum sensors” M. Siciliani de Cumis, F. Marino, M. Anderlini, F. S. Cataliotti, F. Marin, E. Rimini, G. D’Arrigo Advances in Science and Technology , (2008)
“Macroscopic Quantum Entanglement in Light Reflection from Bose-Einstein Condensates” F. De Martini, F. Sciarrino, N. Spagnolo, C. Vitelli, F. S. Cataliotti International Journal of Quantum Information 7,  (2008)
“Radiation pressure excitation and cooling of a cryogenic micro-mechanical systems cavity” M. Siciliani de Cumis, A. Farsi, F. Marino, G. D'Arrigo, F. Marin, F.S. Cataliotti, E. Rimini Journal of Applied Physics 106(1), , (2009).
“Hidden order in bosonic gases confined in one dimensional optical lattices” L. Amico, G. Mazzarella, S. Pasini and F.S. Cataliotti New Journal of Physics . 12, (2010).
“Coherent scattering of a Multiphoton Quantum Superposition by a Mirror-BEC” F. De Martini; F. Sciarrino; C. Vitelli and F.S. Cataliotti Phyical Review Letters, 104, (2010).
“Classical signature of ponderomotive squeezing in a suspended mirror resonator”
F. Marino, F. S. Cataliotti, A. Farsi, M.Siciliani de Cumis and F. Marin
Phyical Review Letters, 104, (2010).