3 ➟ ➠ ➡ ➢ ➤ ➥ ➦ ➧ ➨ ➩ ➫ ➭ ➯ ➲ ➳ ➵ ➸➺ ➻ ➼ ➽ ➾ ➚ ➪ ➶ ➹ ➘ ➴ ➷ ➬ ➮ ➱ ✃ ❐ ❒ ❮ ❰ GLYPH<a207> GLYPH<a208> GLYPH<a209> GLYPH<a210> GLYPH<a211> GLYPH<a212> GLYPH<a213> GLYPH<a214> GLYPH<a215> GLYPH<a216> GLYPH<a217> GLYPH<a218> GLYPH<a219> FIG. 4: The measured threshold behavior of the emitted anti- Stokes light in Fig. 3(b) as a function the pump beam power. The temperature of the Rb cell is T = 105 $^{0}$C . (c) (b) (a) ✐ ❥ ❦ ❧ ♠ ♥ ♦ ♣ GLYPH<a113> GLYPH<a114> GLYPH<a115> GLYPH<a116> ✉ ✈ ✇ ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ⑩ ❶ ❷ ❸ ❹ ❺ ❻ ❼ ❽ ❾ ❿ ➀ ➁ ➂ ➃ ➄ ➅ ➆ ➇ ➈ ➉ ➊ ➋ ➌ ➍ ➎ ➏ ➐ ➑ ➒ ➓ ➔ → ➣ ↔ ↕ ➙ ➛ ➜ ➝ ➞ p p p optical cavity. The modified large dispersions due to the intracavity dense atomic medium are very important in allowing such triple-resonant conditions to be simultane- ously satisfied. Such experimental system can be useful to study atom-cavity interaction, especially for quantum entangled beams in quantum information processing [21]. $^{†}$Corresponding author’s email address: jzhang74@yahoo.com, jzhang74@sxu.edu.cn We thanks K. Peng, C. Xie and T. Zhang for the helpful discussions. This research was supported in part by NSFC for Distinguished Young Scholars (Grant No. 10725416), National Basic Research Program of China (Grant No. 2006CB921101), NSFC Project for Excellent Research Team (Grant No. 60821004), and NSFC (Grant No. 60678029). M. X. acknowledges the funding support from NSF (US). level atoms can be very efficient. The current double-Λ atomic configuration is an ideal system to generate corre- lated Stokes and anti-Stokes photon pairs [20]. With such atomic medium inside an optical cavity and driven above oscillation thresholds, bright correlated twin beams can be obtained, similar to the triple-resonant nondegener- ate OPOs above thresholds with χ (2) nonlinear crystal [12–19]. The bright Stokes and anti-Stokes cavity output beams above threshold will possess the different quan- tum characteristics comparing with that produced from single-pass four-wave mixing process with coherent signal injection [20]. Many interesting phenomena can be real- ized using this demonstrated triple-resonant OPO system in double-Λ atomic system, especially with easily man- aged large intracavity dispersions. In conclusion, we have experimentally demonstrated si- multaneous resonances of the generated Stokes and anti- Stokes fields, together with the single pump field, in an FIG. 3: The scanned F-P cavity transmission spectra. (a) , (b) and (c) show the generated Stokes and anti-Stokes fields when the pump frequency is set at different positions a, b, and c respectively as indicated in Fig. 2(a). The temperature of the vapor cell is set at 105 $^{0}$C . [1] P. Kumar and J. H. Shapiro, Opt. Lett. 10 , 226 (1985). [2] D. Grandclement, G. Grynberg, M. Pinard, Phys. Rev. Lett. 59 , 44 (1987). [3] J. Donoghue, M. Cronin-Golomb, J. S. Kane, and P. R. Hemmer, Opt. Lett. 16 , 1313 (1991). [4] M. Poelker, P. Kumar, and S.-T. Ho, Opt. Lett. 16 , 1853 (1991). [5] M. Poelker and P. Kumar, Opt. Lett. 17 , 399 (1992). [6] P. R. Hemmer, D. P. Katz, J. Donoghue, M. Cronin- Golomb, M. S. Shahriar, and P. Kumar, Opt. Lett. 20 , 982 (1995) [7] J. Okuma, N. Hayashi, A. Fujisawa, M. Mitsunaga, and K. Harada, Opt. Lett. 34 , 698 (2009). [8] H. Wu, M. Xiao and J. Gea-Banacloche, Phys. Rev. A 78 , 041802(R) (2008). [9] R. Guzman, J. C. Retamal, E. Solano, and N. Zagury, Phys. Rev. Lett. 96 , 010502 (2006). [10] H. Xiong, M. O. Scully, and M. S. Zubairy, Phys. Rev. Lett. 94 , 023601 (2005).