Synopsis: Designer photon lifetimes

Short and long photon lifetimes have been custom engineered in a resonant microwave cavity.
Synopsis figure
Illustration: J. P. Leek et al., Phys. Rev. Lett. (2010)

Several proposals for quantum information processing rely on precise control of photon lifetimes and the interactions between atoms and light. This can be achieved by cavity quantum electrodynamics—storing and studying light in a high-quality resonant structure. Ideally, one would want to store photons in such elements for a long time, but then read out the state of the stored mode quickly. With an eye toward scalable quantum computing devices, some of these capabilities have been implemented at microwave wavelengths on microfabricated chips in the form of “circuit QED.”

Writing in Physical Review Letters, Peter Leek and colleagues at the Eidgenössische Technische Hochschule in Zürich, Switzerland, report their ability to engineer very different photon lifetimes in two resonant modes of the same on-chip cavity. The trick used to achieve this is to couple radiation in and out of the center of the cavity, where only the full wavelength modes have a nonzero electric field. Sideband transitions couple qubits in the cavity to various resonant modes. Leek et al. observed a stored photon with a lifetime of 1.45 microseconds in one mode, while the readout mode exhibited a lifetime of only 39 nanoseconds. In addition to photon storage, Leek et al. were able to create Fock states (photon number coherent states) and Bell states (nonlocal entangled states), all essential steps toward useful quantum information processing building blocks. – David Voss


Features

More Features »

Announcements

More Announcements »

Subject Areas

Quantum Information

Previous Synopsis

Soft Matter

Entangled in tubes

Read More »

Next Synopsis

Fluid Dynamics

Drying out in 3D

Read More »

Related Articles

Viewpoint: Seeing Scrambled Spins
Atomic and Molecular Physics

Viewpoint: Seeing Scrambled Spins

Two experimental groups have taken a step towards observing the “scrambling” of information that occurs as a many-body quantum system thermalizes.   Read More »

Viewpoint: Type-II Dirac Fermions Spotted
Quantum Information

Viewpoint: Type-II Dirac Fermions Spotted

Three separate groups report experimental evidence of novel type-II Dirac quasiparticles, suggesting possible applications in future quantum technology. Read More »

Viewpoint: A Roadmap for a Scalable Topological Quantum Computer
Condensed Matter Physics

Viewpoint: A Roadmap for a Scalable Topological Quantum Computer

A team of experimentalists and theorists proposes a scalable protocol for quantum computation based on topological superconductors. Read More »

More Articles