ITAMPblog
Posts related to ITAMP, activities at ITAMP, and all things on ITAMP
Monday, October 19, 2015
Time dilation affecting quantum superpositions
Wednesday, July 31, 2013
Binding together repelling atoms
*presently at the Institute for Theoretical Physics at Leibniz Universität Hannover, Germany
Friday, May 17, 2013
ITAMP 2013 DAMOP presentations (Quebec City Canada)
James Babb4:00 PM–4:00 PM, Tuesday, June 4, 2013
Room: 400A
Abstract: D1.00131 : Rydberg helium and the helium dimer: Relativistic and retardation effects
http://meeting.aps.org/Meeting/DAMOP13/Event/194145
Johannes Feist
Room: 400A
4:00 PM–4:00 PM, Tuesday, June 4, 2013
Room: 400A
Abstract: D1.00061 : Thermodynamics of systems of aligned dipoles
http://meeting.aps.org/Meeting/DAMOP13/Event/194075
X.Y. Yin
Room: 400A
Doerte Blume
Seyed Ebrahim Gharashi
3:00 PM–3:12 PM, Thursday, June 6, 2013
Room: 200A
Abstract: P1.00003 : Correlations of the metastable branch of harmonically-trapped one-dimensional two-component Fermi gases
http://meeting.aps.org/Meeting/DAMOP13/Event/194605
Doerte Blume
Doerte Blume
Janine Shertzer
Room: 303
Abstract: U7.00006 : Scattering properties of three ultracold atoms in a cylindrical waveguide geometry
Room: 303
Abstract: U7.00007 : Non-universal bound states of two identical heavy fermions and one light particle
Tony Lee
Sarang Gopalakrishnan
Mikhail Lukin
Room: 204
Abstract: Dissipative phase transitions in anisotropic spin models
Room: 202
Abstract: H3.00007 : Long-range spatial correlations in a driven-dissipative system of Rydberg atoms
Mikhail Lemeshko
Hendrik Weimer
Room: 202
Abstract: J3.00006 : Dissipative binding of atoms by non-conservative forces
Room: 200B
Abstract: N2.00008 : Quantum phases of quadrupolar Fermi gases in optical lattices
Charles Mathy
Michael Knap
Eugene Demler
Room: 202
Abstract: Quantum flutter versus Bloch oscillations in one-dimensional quantum liquids out of equilibrium
Room: 202
Abstract: B3.00007 : Measurement backaction on a spinor condensate from off-resonant light
Room: 302
Abstract:T6.00003 : Cooling of Nuclear Spins in Diamond via Dark State Spectroscopy
Room: 200B
Abstract: J2.00001 : Strongly interacting quantum phases of polarized dipolar bosons in multi-layered optical lattice
Room: 303
Abstract: U7.00007 : Non-universal bound states of two identical heavy fermions and one light particle
Room: 400A
Abstract: K1.00131 : Electron scattering from excited states of H: derivation of the ionization threshold law
Room: 303
Abstract: U7.00006 : Scattering properties of three ultracold atoms in a cylindrical waveguide geometry
Friday, April 19, 2013
Quadrupolar atoms and molecules as a new platform to study many-body physics
Friday, February 8, 2013
Collective Qubits Compute Faster
Quantum computers can solve certain problems much faster than their classical counterparts, but their realization on a scale relevant for practical applications has proven to be very difficult. However, this could change with a new method for solid state quantum computers devised at ITAMP. We report our results in the journal Physical Review Letters.
While controlling single quantum bits ("qubits") is nowadays possible with high precision, the realization of large networks with many qubits remains an outstanding challenge. This is particularly relevant for devices based on magnetic impurities in solid state systems, where the magnetic interaction between the qubits is too weak. However, the research team could now show that this obstacle could be solved by grouping about 100 impurities to form a single collective qubit. When an external magnetic field is chosen correctly, the magnetic properties of the impurities lose their individual characteristics and become indistinguishable due to their quantum nature. Such collective quantum states are known to show drastically increased interaction strengths, allowing to perform faster quantum logic operations between the collective qubits.
While the proposed method is applicable for a large class of solid state qubits, the scientists present a detailed analysis for nitrogen-vacancy defect centers in diamond, demonstrating the realizability of much larger quantum networks. As few as 50 collective qubits are sufficient for immediate applications in the simulation of strongly correlated quantum systems.
Reference: Hendrik Weimer, Norman Y. Yao, Mikhail D. Lukin. Collectively enhanced interactions in solid-state spin qubits, Physical Review Letters 110, 067601 (2013).
Tuesday, August 7, 2012
ICAP 2012
Misha Lemeshko presented a poster "Dynamically engineering strongly-interacting phases in ultracold dipolar gases" [pdf], describing his recent work in collaboration with Hendrik Weimer and Roman Krems.
Monday, July 16, 2012
Building a crystal out of quantum bricks
Our proposed technique builds on the dipole blockade of microwave excitations. In the context of an effective spin-1/2 model, the dipole blockade allows to flip particular spins in an optical lattice without a need for single-site addressing. The growth of the spin crystal is started by a short sequence of microwave pulses that create a few flipped spins, serving as a nucleation center of the crystalline phase. After that, continuous microwave driving propagates the boundary of the crystal, adding one additional flipped spin after the other.
We investigate the dynamics under the continuous driving and demonstrate that the growth of the ordered domains is efficient. The analysis of the imperfections and the required experimental parameters shows that structures consisting of more than 1,000 spins can be grown. The average size of the resulting domains scales substantially more favorable compared to the conventional adiabatic preparation.
Reference: Mikhail Lemeshko, Roman V. Krems, and Hendrik Weimer,
"Nonadiabatic Preparation of Spin Crystals with Ultracold Polar Molecules",
Phys. Rev. Lett. 109, 035301 (2012).
About the authors: Misha Lemeshko and Hendrik Weimer are the ITAMP Postdoctoral Fellows at the Harvard-Smithsonian Center for Astrophysics and Harvard Physics Department; Roman Krems is an Associate Professor of Chemistry at the University of British Columbia in Vancouver.