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!