Optical parametric oscillator for molecular spectroscopy

用于不同目的的光学参量振荡器：研究项目I：氢分子转动-振动跃迁的精确测量氢分子转动-振动跃迁频率的精确光谱开辟了一种新的方法来测量几个基本常数(里德伯格常数、氢与质子的质量比、电子与质子的质量比、质子电荷半径、氢的四极矩)。光学参量振荡器用于(I)异核和同核氢分子的内态制备，(Ii)用一种新的方法无损地读出异核分子离子的态，以及(Iii)进行新的(电偶极-禁止)跃迁的可行性研究。所获得的结果完全独立于带有Penning陷阱的质子、氘和电子质量的互补测量，以及氢和氢的光谱。因此，氢分子离子光谱学是这些测量的重要验证，并提高了基本常数的一致性和准确性。此外，氢分子离子也是可用于测试新技术的测试系统，然后可以转移到其他分子离子。研究项目II：单片光学谐振器光学材料的研究在未来，计划在室温和低温下对硅晶体在近红外和中红外范围(1.4到4.0微米，所要求的光学参量振荡器的发射范围)的光吸收进行系统测量。其目的是识别不同制造商的晶体和具有非常低吸收损失的相关波长。一旦确定了合适的材料，就可以在合适的真空条件下设计、建造、操作和表征单片谐振器。无源单片谐振器为基础物理开辟了新的可能性。它可以用来探测与精细结构常数耦合的含时(假设)基场。暗物质可能包含这样的场。

The optical parametric oscillator applied for shall be used for different purposes:Research Project I: Precision Measurement of Rotation-Vibration Transitions in Hydrogen MoleculesPrecision spectroscopy of rotational-vibration transition frequencies in hydrogen molecules opens a new approach to several fundamental constants (Rydberg constant, mass ratios of deuteron to proton, electron to proton, proton charge radius, deuteron charge radius, and quadrupole moment of deuteron). The optical parametric oscillator is required (i) for the internal state preparation of hetero- and homonuclear hydrogen molecules, (ii) for non-destructive read-out of the state of heteronuclear molecule ions using a novel method, and (iii) for conducting feasibility studies on novel (electrically dipole-forbidden) transitions.The obtained results are completely independent from complementary measurements of proton, deuteron and electron masses with Penning traps, as well as from hydrogen and deuterium spectroscopy. Thus hydrogen molecular ion spectroscopy is an important verification of these measurements and improves the consistency and probably also the accuracy of the fundamental constants.In addition, hydrogen molecular ions are also test systems that can be used to test novel techniques, which can then be transferred to other molecular ions.Research Project II: Studies on optical materials for monolithic optical resonatorsIn the future, systematic measurements of the optical absorption of silicon crystals in the near and mid infrared range are planned (1.4 to 4.0 µm, emission range of the requested optical parametric oscillator), both at room and cryogenic temperatures. The aim is to identify crystals of different manufacturers and associated wavelengths with very low absorption losses. Once a suitable material has been identified, a monolithic resonator is designed, constructed, operated and characterized under suitable vacuum conditions.A passive monolithic resonator opens up new possibilities for fundamental physics. It can be used to detect a time-dependent (hypothetical) fundamental field coupling to the fine structure constant. Dark matter could contain such fields.