The ‘breath’ between atoms — a new building block for quantum technology

Science Daily  June 1, 2023 Quantum light sources in which coupling between single photons and phonons can be controlled and harnessed enables quantum information transduction. Researchers at the University of Washington created quantum emitters featuring highly tunable coupling between excitons and phonons. The quantum emitters were formed in strain-induced quantum dots created in homobilayer WSe2. The colocalization of quantum-confined interlayer excitons and terahertz interlayer breathing-mode phonons, which directly modulated the exciton energy, led to a uniquely strong phonon coupling to single-photon emission. Due to the vertical dipole moment of the interlayer exciton, the phonon–photon interaction was electrically tunable to be […]

Chip circuit for light could be applied to quantum computations

Phys.org  January 3, 2023 While substantial progress has been made, separately, towards ultra-low loss chip-scale photonic circuits and high brightness single-photon sources, integration of these technologies has remained elusive. An international team of researchers (USA – National Institute of Standards and Technology, University of Maryland, research org., MIT, UC Santa Barbara, industry, Brazil, South Korea) integrated a quantum emitter single-photon source with a wafer-scale, ultra-low loss silicon nitride photonic circuit to demonstrate triggered and pure single-photon emission into a Si3N4 photonic circuit with ≈ 1 dB/m propagation loss at a wavelength of ≈ 930 nm. They observed resonance fluorescence in the strong drive regime, showing promise […]

Tailored single photons: Optical control of photons as the key to new technologies

Nanowerk April 6, 2022 Several different approaches to realize solid-state quantum emitters with high performance have been pursued and different concepts for energy tuning have been established. However, the properties of the emitted photons are always defined by the individual quantum emitter and can therefore not be controlled with full flexibility. An international team of researchers (Germany, USA – University of Arizona) has developed an all-optical nonlinear method to tailor and control the single photon emission. They demonstrated a laser-controlled down-conversion process from an excited state of a semiconductor quantum three-level system. Based on this concept, they realized energy tuning […]

Remote control for quantum emitters

Science Daily  March 12, 2021 An international team of researchers (Austria, Spain) developed a method to individually address quantum emitters using tailored light pulses based on chirped light. In structures with certain electromagnetic properties, such as waveguides, the frequencies propagate at different speeds. If the initial conditions of the light pulse is correctly set, the pulse compresses itself at a certain distance. They analytically describe how the compression distance and width of the pulse can be tuned through its initial parameters. They showed that the interaction of such pulses with a quantum emitter is highly sensitive to its position due […]