A homonuclear molecule with a permanent dipole moment

Traditional wisdom tells us that homonuclear molecules cannot have a permanent dipole moment. However, when one of the atoms in a diatomic molecule is in a highly excited Rydberg state, the exchange symmetry between the two atoms is broken. In a new article published today in Science [1], ITAMP postdoc Seth Rittenhouse and scientist Hossein Sadeghpour in collaboration with groups from the Max-Planck-Institut für Physik komplexer Systeme and the University of Stuttgart, we describe the first direct measurement of a homonuclear, diatomic molecule with a permanent electric dipole moment.

Giant Rydberg molecules, first predicted over a decade ago [2], can bond courtesy of frequent scattering of the Rydberg electron off of a ground state atom. These molecules were later observed spectroscopically in s-wave dominated states [3]. However, because the electronic distribution was assumed to be isotropic, it was thought that this type of molecule would not have any polar behavior.

In our new work, we show that in truth a very small amount of the so-called "trilobite" state is admixed to the molecular electronic state resulting in appreciable dipole moments (on the order od 1 Debye). This prediction is born out by the observation of a linear Stark shift a small fields in high precision spectroscopic measurements of the Stark map of homonuclear rubidium Rydberg molecules.

(a) The electron density for a Giant homonuclear molecule is show in cylindrical coordinates. (b) The trilobite-like electron density is shown after the isotropic amplitude has been subtracted. In both figures the Rb Rydberg core is at z = ρ = 0, the while the ground state atom is located z = 1900 atomic units (figure from Ref. [1]).


References:
[1] W. Li, T. Pohl, J. M. Rost, S. T. Rittenhouse, H. R. Sadeghpour, J. Nipper, B. Butscher, J. B. Balewski, V. Bendkowsky, R. Low and T. Pfau, Science 334, 1110 (2011).

[2] H. R. Sadeghpour, A. S. Dickinson and C. H. Greene, Phys. Rev Lett. 85, 2458 (2000).

[3] V. Bendkowsky et al., Nature 458, 1005 (2009).

Watching correlated electron motion with attosecond pulses

In a recent paper published in Physical Review Letters, we propose a new approach to observe the correlated motion of two electrons on the attosecond timescale. In this pump-probe setup, two identical extreme-ultraviolet light pulses with a duration of just a few hundred attoseconds (1 as = 10^-18 s) are sent onto a helium atom. We expect that with the continuing development of intense attosecond pulses, this kind of experiment could be performed in the next few years. Most current experiments use a strong few-femtosecond infrared field in combination with an extreme-ultraviolet attosecond pulse. These rely on highly nonlinear effects to attain subcycle time resolution within the infrared pulse. In contrast to such setups, the wave packet dynamics are not modified by the fields when using two extreme ultraviolet pulses. The proposed measurement would thus be one of the first experiments to directly observe field-free correlated electron dynamics in atoms on their natural attosecond timescale.

In our proposed setup, the first (pump) pulse excites a coherent wave packet of doubly excited states. These are prototypical examples of highly correlated states where the two electrons influence each other strongly. After letting this wave packet evolve for some time, the second (probe) pulse ejects both electrons. By repeating the sequence many times with different time delays between the two pulses, a "movie" of the doubly excited wave packet can be created frame by frame. 

In the paper, we show that by measuring only one of the two ejected electrons and counting only those electrons within a specific energy interval, it is possible to gain direct access to an observable related to the dynamics of both electrons: the distance between them at the moment of ionization.

There is one further problem to overcome: Both steps in the pump-probe sequence only occur with small probabilities. Both in double excitation (pump) and in double ionization (probe), absorption of one photon has to lead to a two-electron transition. As a photon only "talks" to one electron directly, these two-electron transitions are quite unlikely. We show that one can exploit quantum interference to increase the magnitude of the signal: Since the pump and probe pulses are identical, absorption of two photons from just one of them leads to the same final states as absorption of one photon from each pulse. This "direct" pathway, where each photon ejects one electron, is orders of magnitude more likely than the more interesting pump-probe pathway. However, it does not represent an incoherent background that masks the signal of interest. Instead, it provides a coherent reference pathway that the pump-probe pathway through the doubly excited states interferes with. The amplitude of the interference term is about a hundred times larger than the magnitude of the pump-probe signal by itself, thus providing an experimentally more accessible signal.

Reference: J. Feist, S. Nagele, C. Ticknor, B. I. Schneider, L. A. Collins, and J. Burgdörfer, Phys. Rev. Lett. 107, 093005 (2011)

What is causing trapped ions to heat up? In an ion trap, electrodes (shown here in gold) produce electric fields that confine the ion (green sphere) to a small volume. Randomly fluctuating dipoles on the surface of these electrodes generate electric field noise. The dipoles form when single atoms adsorb on the metal surface. Vibrations (phonons) in the metal cause the dipoles (purple arrows) to fluctuate. Ions trapped in the vicinity of the metal surface sense these electric field changes and heat up.

Viewpoint

Atomic and Molecular Physics

Physics 4, 66 (2011)DOI: 10.1103/Physics.4.66

All that is gold does not glitter

Nikos Daniilidis and Hartmut HäffnerDepartment of Physics, University of California, Berkeley, CA 94720-7300, USA

Published August 22, 2011

A microscopic model offers new insight into a pernicious source of electric field noise in ion traps.

More here ....

A Viewpoint on:

Microscopic model of electric-field-noise heating in ion traps

A. Safavi-Naini, P. Rabl, P. F. Weck, and H. R. Sadeghpour

Phys. Rev. A 84, 023412 (2011) – Published August 22, 2011

Download PDF (free)

Artificial Atoms Can Do More Than Atoms

In a recently published work in Physical Review Letters, we have shown that artificial atoms made of a large number of single atoms can exhibit superior properties compared to their individual counterparts. Our results provide a way to novel applications in photonic devices used for quantum communication and quantum metrology.

In our work, we investigate an ensemble of strongly interacting atoms as found in Rydberg atoms or semiconductor quantum dots. The interaction of these systems with light can be described by an artificial atom with only two energy levels. However, when applying controlled noise to the system, this approximation breaks down and additional energy levels have to be taken into account. If a light beam is then sent through the system, these additional levels result in exactly one photon being removed from the beam. This single photon absorption process can be used in number resolving photon counters or for the creation of non-classical states of light.

Reference: J. Honer, R. Löw, H. Weimer, T. Pfau, H. P. Büchler, Phys. Rev. Lett. 107, 093601 (2011).
See also: Synopsis in Physics

ITAMP 2011 DAMOP presentations (in Atlanta, GA)

 Babb

10:30 AM–12:30 PM, Tuesday, June 14, 2011
Room: A705
Chair: Ed Eyler, University of Connecticut

Abstract: B5.00007 : Partial derivatives of eigenvalues without finite differences

11:42 AM–11:54 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147020

Babb

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC
Abstract: E1.00059 : Long-Range Three-Body Dispersion Interactions

http://meetings.aps.org/Meeting/DAMOP11/Event/147137

Capogrosso

8:00 AM–10:00 AM, Wednesday, June 15, 2011
Room: A704

Chair: Nathan Gemelke, Pennsylvania State University

Abstract: H4.00003 : Pair-Supersolidity of Dipoles in a Bilayer System

8:42 AM–8:54 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147294

Capogrosso

10:30 AM–12:30 PM, Thursday, June 16, 2011
Room: A602

Chair: Markus Greiner, Harvard University

Abstract: N2.00005 : Quantum magnetic phases in harmonically trapped two-component bosons

11:18 AM–11:30 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147674

Demler

10:30 AM–12:30 PM, Tuesday, June 14, 2011
Room: A704
Chair: Benjamin Lev, University of Illinois at Urbana-Champaign

Abstract: B4.00005 : Quantum Magnetism with Polar Alkali Dimers

11:54 AM–12:06 PMhttp://meetings.aps.org/Meeting/DAMOP11/Event/147010

 Demler
4:00 PM–4:00 PM, Tuesday, June 14, 2011

Room: Atrium Ballroom BC
Abstract: E1.00012 : Emulating Quantum Magnetism and t--J Models in Systems of Ultracold Polar Molecules

http://meetings.aps.org/Meeting/DAMOP11/Event/147090

Demler
0:30 AM–12:30 PM, Thursday, June 16, 2011
Room: A705
Chair: Josh Zirbel, University of Illinois at Urbana-Champaign
Abstract: N5.00003 : Non-Equilibrium Dynamics of 1d Bose Gases Studied via Noise Distributions
10:54 AM–11:06 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147699

Demler

8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A705
Chair: Alex Kuzmich, Georgia Institute of Technology

Abstract: T5.00006 : Robust optical delay lines via topological protection

9:00 AM–9:12 AM http://meetings.aps.org/Meeting/DAMOP11/Event/147977

Demler

 8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A706
Chair: Georg Raithel, University of Michigan

Abstract: T6.00007 : Majorana Fermions in Cold Atom Quantum Wires

9:48 AM–10:00 AM http://meetings.aps.org/Meeting/DAMOP11/Event/147989

Feist

2:00 PM–4:00 PM, Wednesday, June 15, 2011
Room: A705

Chair: Arvinder Sandhu, University of ArizonaAbstract: K5.00003 : Attosecond pump-probe of doubly excited states in helium

2:24 PM–2:36 PM http://meetings.aps.org/Meeting/DAMOP11/Event/147406

Feist

2:00 PM–4:00 PM, Thursday, June 16, 2011
Room: A602

Chair: David Reis, SLAC and Standford University

Abstract: P2.00003 : Time-resolved photoemission by attosecond streaking: extraction of time information

2:42 PM–2:54 PM
http://meetings.aps.org/Meeting/DAMOP11/Event/147726

Gacesa

8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A601

Chair: Steven Manson, Georgia State University

Abstract: T1.00006 : Energy transfer in collisions of atmospheric O and H$_2$

9:36 AM–9:48 AM

 http://meetings.aps.org/Meeting/DAMOP11/Event/147948

Kharchenko

8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A601

Chair: Steven Manson, Georgia State University

Abstract: T1.00006 : Energy transfer in collisions of atmospheric O and H$_2$

9:36 AM–9:48 AM
 http://meetings.aps.org/Meeting/DAMOP11/Event/147948

Kuznetsova

8:00 AM–10:00 AM, Thursday, June 16, 2011
Room: A705
Chair: Emily Edwards, JQI and University of Maryland

Abstract: M5.00007 : Cluster state generation using long-range interactions

9:12 AM–9:24 AMhttp://meetings.aps.org/Meeting/DAMOP11/Event/147652

Kuznetsova

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC
Abstract: Q1.00147 : Rydberg molecules mediated interaction between polar molecules: a new tool to realize two-qubit gates

http://meetings.aps.org/Meeting/DAMOP11/Event/147915

 Loreau

10:30 AM–12:30 PM, Wednesday, June 15, 2011
Room: A703

Chair: Francis Robicheaux, Auburn University

Abstract: J3.00009 : Isotope effect on charge transfer in collisions of H with He$^+$ and He$^{2+}$

12:06 PM–12:18 PM
http://meetings.aps.org/Meeting/DAMOP11/Event/147340

 Lukin

10:30 AM–12:30 PM, Tuesday, June 14, 2011
Room: A703
Chair: Gretchen Campbell, JQI and NIST
Abstract: B3.00009 : Sub-wavelength optical trapping and manipulation using far-field optics
12:06 PM–12:18 PM http://meetings.aps.org/Meeting/DAMOP11/Event/147003

 Lukin

10:30 AM–12:30 PM, Tuesday, June 14, 2011
Room: A704

Chair: Benjamin Lev, University of Illinois at Urbana-Champaign

Abstract: B4.00005 : Quantum Magnetism with Polar Alkali Dimers

11:54 AM–12:06 PM http://meetings.aps.org/Meeting/DAMOP11/Event/147010

Lukin

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00012 : Emulating Quantum Magnetism and t--J Models in Systems of Ultracold Polar Molecules

 http://meetings.aps.org/Meeting/DAMOP11/Event/147090

Lukin

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00096 : Towards room temperature magnetic sensing of a single electron spin in biological systems

http://meetings.aps.org/Meeting/DAMOP11/Event/147174

 Lukin

 4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00042 : A Nanoplasmonic Lattice for Quantum Simulation with Cold Atoms

 http://meetings.aps.org/Meeting/DAMOP11/Event/147120

 Lukin   

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00097 : All optical real-time measurement and preparation of nuclear spin states around an individual NV center in diamond

 http://meetings.aps.org/Meeting/DAMOP11/Event/147175

  Lukin  

 4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00098 : Measurement-Based Nuclear Spin Cooling in NV Centers

 http://meetings.aps.org/Meeting/DAMOP11/Event/147176

 Lukin 

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00099 : Sensing thermal motion of a mechanical resonator using a single spin qubit in diamond

http://meetings.aps.org/Meeting/DAMOP11/Event/147177


Lukin  

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00100 : Long-lived solid-state room-temperature quantum memory

http://meetings.aps.org/Meeting/DAMOP11/Event/147178



Lukin  

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00148 : Topologically Protected Quantum State Transfer

http://meetings.aps.org/Meeting/DAMOP11/Event/147226

 Lukin 
4 :00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC
Abstract: E1.00152 : Coupling of NV centers to microscopic cavities
http://meetings.aps.org/Meeting/DAMOP11/Event/147230

 Lukin

8:00 AM–10:00 AM, Wednesday, June 15, 2011
Room: A602
Chair: Tatjana Curcic, Air Force Office of Scientific Research

Abstract: H2.00001 : Optics with Nitrogen Vacancy Centers in Diamond

8:00 AM–8:30 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147273

 Lukin

8:00 AM–10:00 AM, Wednesday, June 15, 2011
Room: A602
Chair: Tatjana Curcic, Air Force Office of Scientific Research

Abstract: H2.00002 : Magnetic field imaging with NV ensembles

8:30 AM–8:42 AM http://meetings.aps.org/Meeting/DAMOP11/Event/147274

 Lukin

4:00 PM–4:00 PM, Wednesday, June 15, 2011
Room: Atrium Ballroom BC

Abstract: L1.00108 : Hybrid Devices for Cavity QED in Solid State Systems

 http://meetings.aps.org/Meeting/DAMOP11/Event/147538

 Lukin

8:00 AM–10:00 AM, Thursday, June 16, 2011
Room: A705
Chair: Emily Edwards, JQI and University of Maryland

Abstract: M5.00004 : Long-range quantum gates using external symmetry breaking

8:36 AM–8:48 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147649

 Lukin
4:00 PM–4:00 PM, Thursday, June 16, 2011

Room: Atrium Ballroom BC

Abstract: Q1.00121 : Nanowire Plasmon Resonators

http://meetings.aps.org/Meeting/DAMOP11/Event/147888

 Lukin

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC
Abstract: Q1.00137 : A nanoscale quantum interface for single atoms

http://meetings.aps.org/Meeting/DAMOP11/Event/147905

 Lukin

8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A703
Chair: Steve Rolston, JQI and University of Maryland

Abstract: T3.00010 : Dark-State Polaritons with Rydberg Interactions

9:48 AM–10:00 AMhttp://meetings.aps.org/Meeting/DAMOP11/Event/147965


Lukin

8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A705
Chair: Alex Kuzmich, Georgia Institute of Technology

Abstract: T5.00006 : Robust optical delay lines via topological protection

9:00 AM–9:12 AMhttp://meetings.aps.org/Meeting/DAMOP11/Event/147977

 Lukin
8:00 AM–10:00 AM, Friday, June 17, 2011

Room: A706
Chair: Georg Raithel, University of Michigan

Abstract: T6.00007 : Majorana Fermions in Cold Atom Quantum Wires

9:48 AM–10:00 AMhttp://meetings.aps.org/Meeting/DAMOP11/Event/147989

Mathy

8:00 AM–10:00 AM, Wednesday, June 15, 2011
Room: A601

Chair: Ken O'Hara, Pennsylvania State University

Abstract: H1.00003 : Universal features of strongly polarized mass imbalanced fermi gases

8:24 AM–8:36 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147264

Rittenhouse

4:00 PM–4:00 PM, Wednesday, June 15, 2011
Room: Atrium Ballroom BC
Abstract: L1.00004 : A Dielectric Superfluid of Polar Molecules

http://meetings.aps.org/Meeting/DAMOP11/Event/147434
  
Rittenhouse

2:00 PM–4:00 PM, Thursday, June 16, 2011
Room: A706

Chair: Doerte Blume, Washington State UniversityAbstract: P6.00003 : Probing universal few-body dynamics

3:00 PM–3:30 PM
http://meetings.aps.org/Meeting/DAMOP11/Event/147764

 Rittenhouse

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC
Abstract: Q1.00008 : Ultralong-range polyatomic Rydberg molecules formed by a polar perturber

 http://meetings.aps.org/Meeting/DAMOP11/Event/147774

 Rittenhouse

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC

Abstract: Q1.00147 : Rydberg molecules mediated interaction between polar molecules: a new tool to realize two-qubit gates

http://meetings.aps.org/Meeting/DAMOP11/Event/147915

 

Sadeghpour

4:00 PM–4:00 PM, Wednesday, June 15, 2011

Room: Atrium Ballroom BC
Abstract: L1.00151 : Self-broadening of helium $^1D$ and $^3D$ lines

http://meetings.aps.org/Meeting/DAMOP11/Event/147582

 

Sadeghpour

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC
Abstract: Q1.00008 : Ultralong-range polyatomic Rydberg molecules formed by a polar perturber

 http://meetings.aps.org/Meeting/DAMOP11/Event/147774

 

Sadeghpour

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC
Abstract: Q1.00147 : Rydberg molecules mediated interaction between polar molecules: a new tool to realize two-qubit gates

http://meetings.aps.org/Meeting/DAMOP11/Event/147915

 

Sadeghpour

10:30 AM–12:30 PM, Wednesday, June 15, 2011
Room: A601
Chair: Jake Taylor, JQI and NISTAbstract: J1.00003 : An ab-initio model of anomalous heating in planar ion traps

10:54 AM–11:06 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147318

Weimer

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC
Abstract: E1.00148 : Topologically Protected Quantum State Transfer

http://meetings.aps.org/Meeting/DAMOP11/Event/147226

Weimer

8:00 AM–10:00 AM, Thursday, June 16, 2011
Room: A705
Chair: Emily Edwards, JQI and University of Maryland

Abstract: M5.00004 : Long-range quantum gates using external symmetry breaking

8:36 AM–8:48 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147649

Yelin

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00097 : All optical real-time measurement and preparation of nuclear spin states around an individual NV center in diamond

http://meetings.aps.org/Meeting/DAMOP11/Event/147175

Yelin 

4:00 PM–4:00 PM, Tuesday, June 14, 2011
Room: Atrium Ballroom BC

Abstract: E1.00098 : Measurement-Based Nuclear Spin Cooling in NV Centers

http://meetings.aps.org/Meeting/DAMOP11/Event/147176

Yelin

8:00 AM–10:00 AM, Wednesday, June 15, 2011
Room: A703
Chair: Ivan Deutsch, University of New Mexico

Abstract: H3.00006 : Superradiance in spin-J atoms: Effects of multiple atomic levels

9:00 AM–9:12 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147286

Yelin

8:00 AM–10:00 AM, Thursday, June 16, 2011
Room: A705
Chair: Emily Edwards, JQI and University of Maryland

Abstract: M5.00007 : Cluster state generation using long-range interactions

9:12 AM–9:24 AM
http://meetings.aps.org/Meeting/DAMOP11/Event/147652

Yelin

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC

Abstract: Q1.00136 : On nearest-neighbor interactions of cold polar molecules in two-color arrays

 http://meetings.aps.org/Meeting/DAMOP11/Event/147904

Yelin

4:00 PM–4:00 PM, Thursday, June 16, 2011
Room: Atrium Ballroom BC

Abstract: Q1.00147 : Rydberg molecules mediated interaction between polar molecules: a new tool to realize two-qubit gates

 http://meetings.aps.org/Meeting/DAMOP11/Event/147915

Zhang

4:00 PM–4:00 PM, Wednesday, June 15, 2011
Room: Atrium Ballroom BC
Abstract: L1.00151 : Self-broadening of helium $^1D$ and $^3D$ lines

http://meetings.aps.org/Meeting/DAMOP11/Event/147582

Zhang 

 8:00 AM–10:00 AM, Friday, June 17, 2011
Room: A601

Chair: Steven Manson, Georgia State University

Abstract: T1.00006 : Energy transfer in collisions of atmospheric O and H$_2$

9:36 AM–9:48 AM
 http://meetings.aps.org/Meeting/DAMOP11/Event/147948

talk by Swati Singh

Swati is talking about hybrid approaches to quantum mechanical cooling, in this case to a BEC as the medium. Phase contrast imaging was used by Stamper-Kurn and Mukund Vengalattore to major the local spin domains in BEC. She is studying the feasibility of measuring the backaction.

Photon scattering losses when objects are levitated to minimize environmental losses, enter the picture. Dipole scattering is not the major issue, as the losses are mostly in the forward direction. Motional squeezing in cantilevers with dipole-dipole interaction, is being discussed. The non-linearity of dipolar interaction is used.

talk by Dan Brooks

He is talking about a microchip trap coupled to a cavity with an optomechanical hamiltonian containing both linear and quadratic couplings of photon and atomic COM. The detuning is about 20 MHz from the cavity resonance, with coupling parameters of order unity (small mass and Young's modulus). In linear coupling regime, the OM power intensity shows a dip when the trap is filled, due to so-called ponderomotive squeezing. The oscillations in the COM motion include a lot of mode excitations and likely the bath mode has frequency dependence.

talk by Oriol Romero-Isart

Oriol is talking about matter wave interferometry with levitating microspheres- real Sch. cats. Two strategies exist for quantum superposition: use the inherent non-linearity or inject non-linearity (with light, for instance). The measurement is done in analogy with atomic physics through "time of flight". Can optomechanics help with interferometry? First cooling, then expansion by TOF, and measure by putting the bead at the node of the cavity. The, allow for more TOF, and measurement of the position. The coupling to the cavity can done thru. linear or quadratic coupling. Using larger matter waves can extend the coupling too. The most important limiting factor is pressure.

talk by Mark Raizen

Mark is discussing how the Brownian motion of macroscopic objects can be controlled. Fabricated microsphere (~ 1 micron diameter) are launched in high voltage and shaken off in air. The largest force turns out to be van der Waals force. The beads scatter photons in the focus of the laser beam. The power spectra of a 3.01 micron bead were shown. The time scale for a 3 micron silica instantaneous motion (velocity) is about 1.2 micro-sec for water and 56 micro-sec for air, giving a resolution restriction of about 100 nano-sec and 4 pico-meter for H_2O and more forgiving for air. The test of equipartition theorem is confirmed.

Now the challenge is to confirm the Brownian motion is water. Preliminary results appear to show ballistic motion- possible breakdown of the equipartition theorem? It shall be seen.

Moving toward the quantum limit; mK cooling of microbeads has been achieved. In arXiv, accepted for publication. Applications: spraying charges and using as thermometer, or for sympathetic cooling of antihydrogen.

on talk by Markus Aspelmayer

Markus is reviewing hi-quality micromechanical systems with atmospheric pressure, 100 ng masses, and 10^-3 N/m spring constants. The mechanical motion is carried away by photon emission from the system.

The non-Markovian nature of the mechanical motion was referred to, as well as single-photon strong coupling beyond the ground state.

The foundational aspect, quantum processing, and quantum metrology are tied here.

talk by Peter Zoller

Peter is reviewing the different schemes for coupling of mechanical oscillators to optical fields and specifically on two topics:

1 - optomechanical transducer for quantum communication, as a way to couple/interface atomic/solid state nodes- in which local computing is done- and transfer them to each other. The implementation of already stationary qubit transfer to other nodes (flying qubit) can be done with --- stay tuned, the webcast audio is being fixed! --- Cascading quantum systems transform to the interaction picture, where there's now a quantum noise term, describing collective decay (Linblad master equation for qubit). There's a unidirectional term in H which describes the emitted photon transfer to the other atom/node.

more on Peter's talk ...

2 - free-space interactions with atoms (in optical lattices). The idea of coupling a cryo-oscillator to an OL under UHV. The backaction of the quantum oscillation of the mirror on the motion of atoms in OL leads to jitter of the optical field and gets a quantum noise. More like the cascading quantum system- a quantum stochastic Schroedinger equation with time delay, which describes the unbalanced atomic motion in the laser field, coupled to the mirror which introduces a phase.

watch this space (today thru. Wed) for blogs on the ITAMP Optomechanics workshop

watch this space for blogs on the ITAMP Optomechanics workshop!