Single-photon-level quantum image memory based on cold atomic ensembles

Ding, Dong-Sheng; Zhou, Zhi-Yuan; Shi, Bao‐Sen; Guo, Guang‐Can

doi:10.1038/ncomms3527

Cited by 211 publications

(139 citation statements)

References 43 publications

Supporting

Mentioning

139

Contrasting

Order By: Relevance

“…With a cold atomic ensemble as the nonlinear medium, the dephasing rate of χ ð3Þ is comparable to the atomic natural linewidth [29][30][31][32][33][34]. In particular, the biphotons generated from spontaneous fourwave mixing (SFWM) in cold atomic ensembles have a coherence time exceeding 1 μs [35,36] with the electromagnetically induced transparency (EIT) effect [37].…”

mentioning

confidence: 88%

Temporal Purity and Quantum Interference of Single Photons from Two Independent Cold Atomic Ensembles

Qian

Cao

et al. 2016

Phys. Rev. Lett.

View full text Add to dashboard Cite

The temporal purity of single photons is crucial to the indistinguishability of independent photon sources for the fundamental study of the quantum nature of light and the development of photonic technologies. Currently, the technique for single photons heralded from time-frequency entangled biphotons created in nonlinear crystals does not guarantee the temporal-quantum purity, except using spectral filtering. Nevertheless, an entirely different situation is anticipated for narrow-band biphotons with a coherence time far longer than the time resolution of a single-photon detector. Here we demonstrate temporally pure single photons with a coherence time of 100 ns, directly heralded from the time-frequency entangled biphotons generated by spontaneous four-wave mixing in cold atomic ensembles, without any supplemented filters or cavities. A near-perfect purity and indistinguishability are both verified through Hong-Ou-Mandel quantum interference using single photons from two independent cold atomic ensembles. The time-frequency entanglement provides a route to manipulate the pure temporal state of the single-photon source. DOI: 10.1103/PhysRevLett.117.013602 The purity of the quantum state of a single photon is a prerequisite of its indistinguishability with single photons from other independent sources, and the latter is an essential basis for the realization of a scalable quantum network with distant and independent nodes [1][2][3][4][5]. Furthermore, the temporal purity of a single photon is crucial to the development of photonic technologies for quantum information science [6,7]. The traditional method to produce indistinguishable single photons is heralding time-frequency entangled biphotons generated from spontaneous parametric down-conversion (SPDC) in a nonlinear crystal which is pumped by ultrashort pulses [4,5,8]. In recent decades many new physical systems have been developed [9-13] to obtain pure single photons without time-frequency entanglement built in.In the community of quantum communication, SPDC in χ ð2Þ nonlinear media is still the preferable way to produce entangled biphotons because of its simplicity in the operation and the potential for on-chip integration and scaling up [14][15][16]. However, the intrinsic feasible phase matching condition of SPDC crystal allows an extremely broad range of temporal modes. Therefore, the typical temporal coherence time of the photon source is of femtosecond scale. Compared to the time response of most commercial single-photon detectors, which is about 1 ns, this temporal coherence time is so short that the trigger photon of the heralded single photon is measured with a large time uncertainty. This time uncertainty damages the temporal quantum purity of the single-photon source. To circumvent the time uncertainty problem due to the slowness of the detectors, a common practice is to use external spectral filtering including passive filtering with narrowband filters [4,5,17] and active filtering with an optical cavity [18]. In this case, the temporal state o...

show abstract

mentioning

confidence: 88%

Temporal Purity and Quantum Interference of Single Photons from Two Independent Cold Atomic Ensembles

Qian

Cao

et al. 2016

Phys. Rev. Lett.

View full text Add to dashboard Cite

show abstract

“…The nonlinear interaction of LG beams with atomic systems has been investigated via four-wave mixing processes [5] and the corresponding conservation of OAM demonstrated both in cold and thermal atoms [6,7]. The storage of OAM in cold and thermal atomic ensembles was also previously demonstrated, both in the classical [9,10] and single photon [11,12] regimes. In the context of quantum computing, the generation of twin light beams carrying OAM with quantum intensity correlation have been demonstrated through four wave mixing (FWM) in thermal rubidium vapor [13] and also the entanglement of the OAM of photon pairs [14,15].…”

Section: Arxiv:14095690v1 [Quant-ph] 19 Sep 2014mentioning

confidence: 99%

Off-axis retrieval of orbital angular momentum of light stored in cold atoms

Oliveira¹,

Pruvost²,

Barbosa³

et al. 2014

Appl. Phys. B

View full text Add to dashboard Cite

show abstract

“…Photons with OAM could be regarded as helices with their left-and right-handedness twisted to varying degrees. Light encoded in OAM space could offer high channel capacity and also can provide capability for spatial manipulating [17] . Many groups and researchers have demonstrated the optical storage of OAM in atomic gas and solid matter systems [18][19][20][21][22] .…”

mentioning

confidence: 99%

Optical storage of orbital angular momentum via Rydberg electromagnetically induced transparency

et al. 2017

View full text Add to dashboard Cite

In this Letter, we report on the successful optical storage of orbital angular momentum (OAM) using Rydberg electromagnetically induced transparency (EIT) in cold rubidium atoms. With a storage time of 1.4 μs, the retrieved structure is highly similar, showing the ability of storing light's OAM at a principal quantum number of 20. The results at higher principal quantum numbers (n ¼ 25; 30) are also measured. These results show the promise of image processing based on a Rydberg atomic system.OCIS codes: 160.2900, 020.5780. doi: 10.3788/COL201715.060201.Photons are robust carriers of information, and memory for the state of light is a key step in the realization of long-distance communications. Many optical memories are based on light-atom interactions, such as electromagnetically induced transparency (EIT) [1,2] , coherent population oscillation (CPO) [3,4] , gradient echo memories [5] , and the atomic frequency comb [6] . The combination of EIT and Rydberg atoms provides an effective interaction between photons. Such a process requires coherently mapping photonic states into and out of a Rydberg polariton on demand. Rydberg atoms are ideal for nonlinear interaction because of the strong dipole-dipole (DD) interaction between the Rydberg atoms [7][8][9] . The strong DD interaction leads to Rydberg blockade and can be used to implement a controlled-NOT gate [10] , single-photon switches [11] , transistors [12] , and a controlled π phase shift [13] . Structured vortex beams with phase front expðilθÞ carry an orbital angular momentum (OAM) of lℏ per photon [14][15][16] , where l is a topological charge and θ represents an azimuthal angle. Photons with OAM could be regarded as helices with their left-and right-handedness twisted to varying degrees. Light encoded in OAM space could offer high channel capacity and also can provide capability for spatial manipulating [17] . Many groups and researchers have demonstrated the optical storage of OAM in atomic gas and solid matter systems [18][19][20][21][22] . The Rydberg interaction, which is dependent on the separation distance between the Rydberg atoms, creates an obstacle on subsequent excitations of neighboring ground state atoms. Such spatial dependent interaction could bring rich spatial dynamics behaviors, showing potential manipulation in image information processing. Moreover, exciting Rydberg atoms with OAM structure gives an additional degree of freedom for manipulating an image. Storing a structured vortex beams as a structured Rydberg collective excitation is a preliminary step.In this Letter, we experimentally investigate the optical storage of OAM in cold rubidium atoms using the Rydberg EIT. We use a time-resolution camera to monitor the spatial structure of the probe beam carrying OAM before and after storage. The storage time could be up to 1.4 μs at a principal quantum number of 20. Higher principal numbers (n ¼ 25; 30) are also given.The experimental setup is similar to our previous device [23] :85 Rb atoms are trapped in two-dimensional magneto-optica...

show abstract

Single-photon-level quantum image memory based on cold atomic ensembles

Cited by 211 publications

References 43 publications

Temporal Purity and Quantum Interference of Single Photons from Two Independent Cold Atomic Ensembles

Temporal Purity and Quantum Interference of Single Photons from Two Independent Cold Atomic Ensembles

Off-axis retrieval of orbital angular momentum of light stored in cold atoms

Optical storage of orbital angular momentum via Rydberg electromagnetically induced transparency

Contact Info

Product

Resources

About