Related papers: Direct observation of non-linear optical phase shi…
Strong nonlinear interactions between photons enable logic operations for both classical and quantum-information technology. Unfortunately, nonlinear interactions are usually feeble and therefore all-optical logic gates tend to be…
Over the past years, there have been many efforts towards generating interactions between two optical beams so strong that they could be observed at the level of individual photons. Such strong interactions, beyond opening up a new regime…
In analogy to transistors in classical electronic circuits, a quantum optical switch is an important element of quantum circuits and quantum networks. Operated at the fundamental limit where a single quantum of light or matter controls…
We exploit the nonlinearity arising from the spin-photon interaction in an InAs quantum dot to demonstrate phase shifts of scattered light pulses at the single-photon level. Photon phase shifts of close to 90 degrees are achieved using a…
Local control of the generation and interaction of indistinguishable single photons is a key requirement for photonic quantum networks. Waveguide-based architectures, in which embedded quantum emitters act as both highly coherent single…
Realizing a strong interaction between individual optical photons is an important objective of research in quantum science and technology. Since photons do not interact directly, this goal requires, e.g., an optical medium in which the…
The lack of interactions between single photons prohibits direct nonlinear operations in quantum optical circuits, representing a central obstacle in photonic quantum technologies. Here, we demonstrate multi-mode nonlinear photonic circuits…
Optical nonlinearities sensitive to individual photons may be extremely useful as elements in quantum logic circuits for photonic qubits. A much cited example is the work of Turchette et al. [Phys. Rev. Lett. 75, 4710 (1995)], in which a…
An outstanding goal in quantum optics is the realization of fast optical non-linearities at the single-photon level. Such non-linearities would allow for the realization of optical devices with new functionalities such as a single-photon…
The ability to control light-matter interfaces with solid-state photon emitters is a major requirement for the development of quantum photonic integrated circuits. We demonstrate controllable coupling between a quantum dot and an optical…
Establishing a highly efficient photon-emitter interface where the intrinsic linewidth broadening is limited solely by spontaneous emission is a key step in quantum optics. It opens a pathway to coherent light-matter interaction for, e.g.,…
We have realized the nonlinear sign shift (NS) operation for photonic qubits.This operation shifts the phase of two photons reflected by a beam splitter using an extra single photon and measurement. We show that the conditional phase shift…
Quantum dots (QDs) are semiconductor nanostructures in which a three dimensional potential trap produces an electronic quantum confinement, thus mimicking the behaviour of single atomic dipole-like transitions. However unlike atoms, QDs can…
Coherent photon-emitter interfaces offer a way to mediate efficient nonlinear photon-photon interactions, much needed for quantum information processing. Here we experimentally study the case of a two-level emitter, a quantum dot, coupled…
Solid-state quantum emitters have long been recognised as the ideal platform to realize integrated quantum photonic technologies. We use a self-assembled negatively charged QD in a low Q-factor photonic micropillar to demonstrate for the…
Coherent quantum optics, where the interaction of a photon with an emitter does not scramble phase coherence, lies at the heart of many quantum optical effects and emerging technologies. Solid-state emitters coupled to nanophotonic…
Recent breakthroughs in solid-state photonic quantum technologies enable generating and detecting single photons with near-unity efficiency as required for a range of photonic quantum technologies. The lack of methods to simultaneously…
The amplitude and phase of a material's nonlinear optical response provide insight into the underlying electronic dynamics that determine its optical properties. Phase-sensitive nonlinear spectroscopy techniques are widely implemented to…
We demonstrate the tunable quantum beat of single photons through the co-development of core nonlinear nanophotonic technologies for frequency-domain manipulation of quantum states in a common physical platform. Spontaneous four-wave mixing…
Access to the electron spin is at the heart of many protocols for integrated and distributed quantum-information processing [1-4]. For instance, interfacing the spin-state of an electron and a photon can be utilized to perform quantum gates…