Quantum Manipulation of Nuclear Spin of Ortho-H2 Molecule in Solid Hydrogen

我们开展了这些研究，为操纵固体氢中正氢分子的核自旋量子相干奠定了基础。同时，我们开发了一种利用纳米光纤操控光学过程的方法；最初提出的是在固体氢中引入强光。在正氢计划的基础上，我们利用双谐振光PO技术研制了一台波长为2.4μm的高稳定单频连续激光器。系统地测量了正氢红外跃迁(v=1-0，J=1-1)。结果表明，该跃迁揭示了1.6 MHz HWHM的超窄谱宽。这个宽度是仅用简单的吸收光谱观察到的最窄的宽度，没有使用任何非线性激光光谱方法。虽然正氢的密度很低，40ppm，但1厘米固体氢晶体的峰值吸收达到了60%，这是由于其超窄的光谱特性所致。我们还证明了振动-旋转sp…更多的Etrtrum分裂成三个分量，分裂幅度约为10 MHz。分裂的原因可以理解为J=1态的磁性简并通过晶场分裂成三个子能级。实验结果表明，固体氢中的正氢是实现固体中量子相干控制的独特体系。对于纳米光纤，我们建立了一种制备直径为1μm到400 nm、透过率为80%的纳米光纤的方法。我们在理论上展示了利用纳米纤维开发光学过程的独特可能性，这与在自由空间中的光学过程非常不同；关键是将光场和原子/分子都限制在纳米纤维周围的亚微米空间中。我们可以仅利用单光子来操控单原子/分子跃迁。此外，纳米光纤附近原子/分子的自发辐射被强烈地修饰为发射光子进入纳米光纤的导模。我们在实验上观察到了2006年2月分娩的独特特征。这些观察表明，纳米纤维技术可能会开启量子光学的一个新领域。较少

We carried out the researches to establish a basis for manipulating nuclear-spin quantum-coherence of ortho-hydrogen molecule in solid hydrogen. Simultaneously, we developed a method to manipulate optical processes using optical nanofiber ; it was originally proposed to introduce a strong light into the solid hydrogen.Regarding the ortho-hydrogen project, we developed a highly-stable single-frequency cw laser at 2.4 μm wavelength using doubly-resonant OPO-technique. Ortho-hydrogen infrared transition (v=1-0, J=1-1) was measured systematically. We showed that the transition reveals an ultra-narrow spectral width of 1.6 MHz HWHM. This width is the narrowest width observed just using simple absorption spectroscopy, without using any nonlinear laser-spectroscopic method. Although density of ortho-hydrogen is very low 40 ppm, the peak absorption of 1-cm solid hydrogen crystal reaches to 60% ; it is due to the ultra-narrow spectral feature. We demonstrated also that the vibration-rotation sp … More ectrum splits into three components with splittings of about 10 MHz. The origin of the splitting may be understood due to breaking of magnetic degeneracy of J=1 state into three sublevels via crystal field. The observations have demonstrated that the ortho-hydrogen embedded in solid-parahydrogen is a unique system for realizing quantum coherence control in solid. The observed degeneracy breaking may open a new possibility to realize a new Raman three level scheme without magnetic field.Regarding the nanofiber, we established a method to produce nanofibers with diameter from 1μm to 400 nm with transmission of 80%. We showed theoretically a unique possibility to develop optical processes using nanofibers, very different from those in free space ; a key point is to confine both optical field and atoms/molecules into a submicron space around a nanofiber. We can manipulate single atom/molecule transition just using single photon. Moreover, spontaneous emission of atom/molecule near the nanofiber is strongly modified to emit photons into a guided mode of a nanofiber. We have observed experimentally the unique features of confinement in February of 2006. The observations imply that the nanofiber technique may open a new category of quantum optics. Less