Events

Frederic Magniez, Université Paris Diderot

We describe a new quantum paradigm, that we call Quantum Chebyshev’s inequality, to approximate with relative error the mean of any random variable with a number of quantum samples that is linear in the ratio of the square root of the variance to the mean. Classically the dependency is quadratic. To illustrate this method, we apply it to the approximation of frequency moments in the multi-pass streaming model, and to the approximation of the number of edges and triangles in the quantum graph query access model.

Spontaneous Raman emission in cold atoms inside a hollow-core waveguide

Taehyun Yoon, Institute for Quantum Computing

Cold atoms confined inside hollow-core waveguides enable strong-matter interactions, thus offer a unique platform for studies of quantum and non-linear optics. We developed an experimental system that traps cesium atoms in a magneto optical trap (MOT) and loads these atoms into a hollow core photonic crystal fiber using a dipole trap at cesium magic wavelength (935 nm), which removes the AC-Stark shift of the optical transition and suppresses the inhomogeneous broadening.

Fabrication and Growth of 111 SiNWs for Mechanical Spin-Detection

Pardis Sahafi, Institute for Quantum Computing

In our group, vertical Si nanowires grown on a 111 surface are used for force detection in nanoscale NMR and ESR. These measurements require a very long (20 µm) and minimally tapered vertical Si nanowires, to be used as nano-mechanical oscillators with a high quality factor (Q ~ 10⁴).

IQC and the Department of Physics at the University of Waterloo welcome Shahpoor Moradi, University of Calgary

Quantum computation has been developed as a computationally efficient paradigm to solve problems that are intractable with conventional classical computers. Quantum computers have the potential to support the simulation and modeling of many complex physical systems, not just quantum ones, significantly more rapidly than conventional supercomputers.

Alvaro Alhambra, Perimeter Institute

Heat-Bath Algorithmic Cooling is a technique for producing pure quantum systems by utilizing a surrounding heat-bath. Here we connect the study of these cooling techniques to the resource theory of athermality, enabling us to derive provably optimal cooling protocols under a variety of experimental restrictions on the available control.

Rescheduled from Tuesday, February 12

QUANTUM + Film: A screening of 10 Quantum Shorts

A festival for quantum-inspired films

The Quantum Shorts festival called for short films inspired by quantum physics and the universe answered. Filmmakers all over the world responded with their movies.

APS March Meeting Student Practice Talk Session

Silicon MOSFET quantum dots with simplified metal-gate geometry

Eduardo Barrera

Silicon (Si) CMOS spin qubits have become a promising platform for a future quantum information processor due to recent demonstrations of high fidelity single and two qubit gates [Veldhorst et. al., Nature 526.7573 (2015)], compatibility with industrial CMOS process and promising prospects for scalability.

Alan Jamison, Massachusetts Institute of Technology (MIT)

Cooling atomic gases to quantum degeneracy opened the new field of quantum simulation. Here the precise tools of atomic physics can be used to study exotic models from condensed matter or nuclear physics with unique tunability and control. Ultracold molecules bring many new possibilities to quantum simulation. I will review the physics of ultracold molecules, including our recent production of stable, ultracold triplet molecules and what they can add to quantum simulation.

Crafting high-dimensional tools for photonic quantum networks with tailored nonlinear optics

John Donohue, Institute for Quantum Computing

The time-frequency degree of freedom of light offers an intrinsically high-dimensional encoding space which is naturally compatible with waveguide devices and fiber infrastructure. However, coherent manipulation and measurement the information-carrying modes presents a challenge due to the sub-picosecond timescales inherent to downconversion-based photon sources. In this talk, I will discuss methods based on ultrafast pulse shaping and sum-frequency generation to address these temporal modes.