Telecommunications-band heralded single photons from a silicon nanophotonic chip

Abstract

We demonstrate room temperature heralded single photon generation in a CMOS-compatible silicon nanophotonic device. The strong modal confinement and slow group velocity provided by a coupled resonator optical waveguide produced a large four-wave-mixing nonlinearity coefficient gamma_eff =4100 W-1 m-1 at telecommunications wavelengths. Spontaneous four-wave-mixing using a degenerate pump beam at 1549.6 nm created photon pairs at 1529.5 nm and 1570.5 nm with a coincidence-to-accidental ratio exceeding 20. A photon correlation measurement of the signal (1529.5 nm) photons heralded by the detection of the idler (1570.5 nm) photons showed antibunching with g(2)(0)=0.19 +/- 0.03. The demonstration of a single photon source within a silicon platform holds promise for future integrated quantum photonic circuits

Single photons from dissipation in coupled cavities

“…Although the degree of control over these systems is steadily improving, they basically operate at cryogenic temperatures and (or) imply significant fabrication challenges, particularly with respect to integration and scalability in future photonic platforms. On the other hand, nondeterministic sources relying on heralding protocols are now operating at room temperature in Silicon [12][13][14][15][16], but they require a significant input power to trigger the four wave mixing mechanism.…”

Unconventional photon blockade in doubly resonant microcavities with second-order nonlinearity

“…It has been recently proposed that single-photon blockade could be achieved in nanostructured cavities either with second-[χ (2) ] [10] or third-order [χ (3) ] [11] nonlinear susceptibility, which can be strongly enhanced by diffraction-limited photonic confinement [12,13]. On the other hand, given the small values of typical nonlinear coefficients of most semiconducting and insulating materials [14], an unconventional photon blockade (UPB) process could facilitate achieving antibunched light emission from suitably engineered coupled modes [15].…”

“…There is currently pressing need for the development of integrated quantum technologies allowing for the generation and manipulation of quantum states of the electromagnetic radiation, with the ultimate goal of defining a photonic-based architecture for quantum information processing [1]. For interfacing with long distance infrastructures based on fiber-optics communication, state-of-art sources of quantum radiation have been lately developed at the typical telecommunication wavelengths, either based on heralding photons [2,3] or on artificial quantum emitters [4]. However, a source of quantum radiation that is not related to any resonant behavior of a quantum emitter, but can be engineered to operate at arbitrary wavelength and work at room temperature has not yet been realized.…”

Deterministic separation of arbitrary photon pair states in integrated quantum circuits

“…Correlated photon pairs are an important resource for quantum photonics that can be generated on-chip by quantum dots [4] or integrated nonlinear waveguides [5,6,14]. As well as being both compact and efficient, integrated photon pair sources have also shown unprecedented versatility in tailoring the properties of the generated twin-photon state through dispersion engineering and birefringence management, thereby establishing control over the spectral and polarization entanglement [15][16][17], photon bandwidths [18], and degree of non-degeneracy.…”

“…Mapping quantum photonic technologies into an integrated on-chip setting has become an important task for overcoming the severe stability and scalability limitations of bulk-optics implementations. Recent efforts have demonstrated on-chip quantum state generation [4][5][6], manipulation [7][8][9][10][11][12] and detection [13] across numerous material platforms including GaAs [6,11,13], silicon wire [5,12], silica-on-silicon [7,8,10], lithium niobate [14] and borosilicate glass [9].…”