Related papers: XPM nonlinearities:Are all involved photons real?
Photonic platforms are an excellent setting for quantum technologies because weak photon-environment coupling ensures long coherence times. The second key ingredient for quantum photonics is interactions between photons, which can be…
Using a gradient echo memory, we experimentally demonstrate cross phase modulation (XPM) between two optical pulses; one stored and one freely propagating through the memory medium. We explain how this idea can be extended to enable…
We report the experimental observations on the simultaneous EIT effects for probe and trigger fields (double EIT) as well as the large cross-phase modulation (XPM) between the two fields in a four-level tripod EIT system of the D1 line of…
Multiphoton interference is an essential phenomenon at the very heart not only of fundamental quantum optics and applications in quantum information processing and sensing but also of demonstrations of quantum computational supremacy in…
Dissipation-free photon-photon interaction at the single photon level is studied in the context of cavity electromagnetically induced transparency (EIT). For a single multilevel atom exhibiting EIT in the strong cavity-coupling regime, the…
Realistic single-photon sources do not generate single photons with certainty. Instead they produce statistical mixtures of photons in Fock states $\ket{1}$ and vacuum (noise). We describe how to eliminate the noise in the output of the…
Photons are bosons, and yet, when prepared in specific entangled states, they can exhibit non-bosonic behaviour. While this phenomenon has so far been studied in two-photon systems, exchange symmetries and interference effects in…
The simplest three-level system exhibiting electromagnetically induced transparency (EIT) exhibits an effective conjugation symmetry as well as a permutation symmetry. Breaking conjugation symmetry leads to a distinct chirp asymmetry; the…
We propose and theoretically investigate a model to realize cascaded optical nonlinearity with few atoms and photons in one-dimension (1D). The optical nonlinearity in our system is mediated by resonant interactions of photons with…
We propose a scheme to achieve a uniform cross phase modulation (XPM) for two nonclassical light pulses and study its application for quantum non-demolition measurements of the photon number in a pulse and for controlled phase gates in…
Nonlinear optical processes associated with even-order nonlinear susceptibilities are critical for both classical and quantum technologies. Inversion symmetry, however, prevents nonlinear optical responses mediated by even-order…
We demonstrate an efficient cross-phase modulation (XPM) based on a closed-loop double-{\Lambda} system. The property of the double-{\Lambda} medium can be controlled by changing the phases of the applied optical fields. This…
Similar to radiation pressure, photothermal effects connect the optical path length to an intracavity field, resulting in nonlinear behavior of the resonator due to thermal effects. Here, we theoretically investigate the nonlinear optics…
Single photons are of paramount importance to future quantum technologies, including quantum communication and computation. Nonlinear photonic devices using parametric processes offer a straightforward route to generating photons, however…
Detecting coherent phonons pose different challenges compared to coherent photons due to the much stronger interaction between phonons and matter. This is especially true for high frequency heat carrying phonons, which are intrinsic lattice…
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…
The coherent nonlinear process where a single photon simultaneously excites two or more two-level systems (qubits) in a single-mode resonator has recently been theoretically predicted. Here we explore the case where the two qubits are…
A framework is established for evaluating {\sc cphase} gates that use single-photon cross-phase modulation (XPM) originating from the Kerr nonlinearity. Prior work Phys. Rev. A {\bf 73,} 062305 (2006)], which assumed that the control and…
We demonstrate the double electromagnetically induced transparency (double-EIT) and double four-wave mixing (double-FWM) based on a new scheme of non-degenerate four-wave mixing (FWM) involving five levels of a cold 85Rb atomic ensemble, in…
We show, that photon non-linearities in electromagnetically induced transparency can be at least one order of magnitude larger than predicted in all previous approaches. As an application we demonstrate that, in this regime they give rise…