Feb 2019: New article in Quantum Science and Technology
Canada ranks among the world’s leading nations in quantum research, building on investments of more than $1 billion in the past decade alone. Canada’s amassed research expertise, growing private-sector impact, and government commitments to innovation and competitiveness, place the country in a strong position, as scientific advances drive quantum technology development. Here, we summarize the steps Canada has taken to build quantum research excellence and to support a growing quantum industrial base. We also discuss Canadian quantum community efforts to solidify and build the nation’s leadership, as the technology revolution unfolds.
Ben Sussman, Paul Corkum, Alexandre Blais, David Cory and Andrea Damascelli
2019 Quantum Sci. Technol. 4 020503
Phys. Rev. Lett. 120, 163002 – Published 16 April 2018
The hydrogen molecule has become a test ground for quantum electrodynamical calculations in molecules. Expanding beyond studies on stable hydrogenic species to the heavier radioactive tritium-bearing molecules, we report on a measurement of the fundamental T2 vibrational splitting (v=0→1) for J=0–5 rotational levels. Precision frequency metrology is performed with high-resolution coherent anti-Stokes Raman spectroscopy at an experimental uncertainty of 10–12 MHz, where sub-Doppler saturation features are exploited for the strongest transition. The achieved accuracy corresponds to a 50-fold improvement over a previous measurement, and it allows for the extraction of relativistic and QED contributions to T2 transition energies.
Consensus Study Report
National Academies of Sciences, Engineering, and Medicine. 2018.
The laser has revolutionized many areas of science and society, providing bright and versatile light sources that transform the ways we investigate science and enables trillions of dollars of commerce. Now a second laser revolution is underway with pulsed petawatt-class lasers (1 petawatt: 1 million billion watts) that deliver nearly 100 times the total world’s power concentrated into a pulse that lasts less than one-trillionth of a second. Such light sources create unique, extreme laboratory conditions that can accelerate and collide intense beams of elementary particles, drive nuclear reactions, heat matter to conditions found in stars, or even create matter out of the empty vacuum.
Rev. Mod. Phys. 88, 015007 – Published 9 March 2016
A new scientific frontier opened in 2009 with the start of operations of the world’s first x-ray free-electron laser (FEL), the Linac Coherent Light Source (LCLS), at SLAC National Accelerator Laboratory. LCLS provides femtosecond pulses of x rays (270 eV to 11.2 keV) with very high peak brightness to access new domains of ultrafast x-ray science. This article presents the fundamental FEL physics and outlines the LCLS source characteristics along with the experimental challenges, strategies, and instrumentation that accompany this novel type of x-ray source. The main part of the article reviews the scientific achievements since the inception of LCLS in the five primary areas it serves: atomic, molecular, and optical physics; condensed matter physics; matter in extreme conditions; chemistry and soft matter, and biology.
Connor Kupchak, Philip J. Bustard, Khabat Heshami, Jennifer Erskine, Michael Spanner, Duncan G. England, and Benjamin J. Sussman
Phys. Rev. A 96, 053812 – Published 6 November 2017
The encoding of quantum information in photonic time-bin qubits is apt for long-distance quantum communication schemes. In practice, due to technical constraints such as detector response time, or the speed with which copolarized time-bins can be switched, other encodings, e.g., polarization, are often preferred for operations like state detection. Here, we present the conversion of qubits between polarization and time-bin encodings by using a method that is based on an ultrafast optical Kerr shutter and attain efficiencies of 97% and an average fidelity of 0.827±0.003 with shutter speeds near 1 ps. Our demonstration delineates an essential requirement for the development of hybrid and high-rate optical quantum networks.
Update Jan 2018 – a presentation covering this work was given at the PQE conference, video and slides are available online.
Update August 2017 – this article is now published in PRL, under the alternative title Molecular Frame Reconstruction Using Time-Domain Photoionization Interferometry.
Phys. Rev. Lett. 119, 083401 (2017), DOI: 10.1103/PhysRevLett.119.083401
(Feb 2017) New manuscript on the arxiv:
(Submitted on 29 Jan 2017)
Photoionization of molecular species is, essentially, a multi-path interferometer with both experimentally controllable and intrinsic molecular characteristics. In this work, XUV photoionization of impulsively aligned molecular targets (N2) is used to provide a time-domain route to “complete” photoionization experiments, in which the rotational wavepacket controls the geometric part of the photoionization interferometer. The data obtained is sufficient to determine the magnitudes and phases of the ionization matrix elements for all observed channels, and to reconstruct molecular frame interferograms from lab frame measurements. In principle this methodology provides a time-domain route to complete photoionization experiments, and the molecular frame, which is generally applicable to any molecule (no prerequisites), for all energies and ionization channels.
arxiv 1701.08432 (2017)
Supplementary material (theory, data and code) available at DOI: 10.6084/m9.figshare.4480349.
Feb. 2017 – New article in Chemical Physics Letters:
Kwanghsi Wang(a) , Vincent McKoy(a), Paul Hockett(b), Albert Stolow(b, c, d),Michael S. Schuurman(b, d),
a A. A. Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, California 91125, USA
b National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
c Department of Physics, University of Ottawa, ON K1N 6N5 Canada
d Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
- • Time-resolved photoelectron angular distributions around conical intersections are studied.
- • Ab initio multiple spawning method is applied to obtain wavepacket densities.
- • Geometry and energy dependent photoelectron matrix elements are employed.
- • Molecular and laboratory photoelectron angular distributions are used to illustrate the non-adiabatic dynamics.
- • Photoelectron spectra are compared with measured values.
We report results from a novel fully ab initio method for simulating the time-resolved photoelectron angular distributions around conical intersections in CS2. The technique employs wavepacket densities obtained with the multiple spawning method in conjunction with geometry- and energy-dependent photoionization matrix elements. The robust agreement of the calculated molecular-frame photoelectron angular distributions with measured values for CS2 demonstrates that this approach can successfully illuminate, and disentangle, the underlying coupled nuclear and electronic dynamics around conical intersections in polyatomic molecules.