Highly Efficient Single-Pass Source of Pulsed Single-Mode Twin Beams of Light

Abstract

We report the realization of a bright ultrafast type II parametric down-conversion source of twin beams free of any spatiotemporal correlations in a periodically poled KTiOPO4 (PP-KTP) waveguide. From a robust, single-pass setup it emits pulsed two-mode squeezed vacuum states: photon-number entangled pairs of single-mode pulses or, in terms of continuous variables quantum optics, pulsed Einstein-Podolsky-Rosen states in the telecom wavelength regime. We verify the single-mode character of our source by measuring Glauber correlation functions g(2) and demonstrate with a pump energy as low as 75 pJ per pump pulse a mean photon number of 2.5.

Spectrally Pure States at Telecommunications Wavelengths from Periodically PoledMTiOXO4(M=Jin1, Zhao2, Deng3 et al. 2016Phys. Rev. Applied210150View full textAdd to dashboardCite

“…Firstly, in addition to the generation of spectrally decorrelated states shown in Fig. 1, it is also possible to prepare spectrally positivelycorrelated or negatively-correlated states by varying the crystal length or pump bandwidth, in a similar manner to which has been demonstrated in the case of a PP-KTP crystal [13]. Secondly, it is useful to demonstrate customized poiling (by modulating the poling-order [31], the duty-cycle [32], or domain-sequence [33,34] ) in these four isomorphs, so as to improve the maximal intrinsically purity from 0.82 to near 1.…”

“…Recently, the study of spectrally pure state generation in a PPKTP crystal has achieved significant progress [11][12][13][14][15][16]. Besides high spectral purity, the PPKTP crystal still have several other merits, such as high brightness (because the crystal can be very long, thanks to the periodically poling technique), high damage threshold (higher than PPLN crystal), wide tunability (more than 200 nm at telecom wavelengths [14]).…”

Deterministic separation of arbitrary photon pair states in integrated quantum circuits

“…This effect is shown in Figure 11; as the state's spectral entanglement and hence Schmidt Number is increased, P S is asymptotically restored towards unity through increases in P 0 S and P I S . In SPDC, spectral entanglement depends partly on the dispersion properties of the source [16,17]. However, it is generally dominated by the amount of wavelength anti-correlation imparted by the pump bandwidth.…”

“…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. A single device can be designed to produce a variety of quantum states.…”

Optimization of periodic single-photon sources based on combined multiplexing

“…In the literature there are two typical ways of realizing a heralded single-photon source (HSPS) based on correlated photon pair generation. The two physical phenomena applied for pair generation are spontaneous four-wave mixing (SFWM) in optical fibers [31][32][33][34] and spontaneous parametric down-conversion (SPDC) in bulk crystals [35][36][37][38][39] or waveguides [40][41][42]. These processes can yield highly indistinguishable single photons in an almost ideal single mode with known polarization [33,35,36,41,43].…”