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We present results for novel design and implementation of a high-power, high-resolution continuous-wave optical parametric oscillator (OPO) emitting mid-infrared radiation tunable from 3−4 μm, with output powers in excess of 2.5 W. Our home-built “JILA OPO” design is based on a periodically poled lithium niobate fanout crystal inside a four-mirror ring cavity singly resonant at the signal wavelength (1.4−1.7 μm). The 50 mm-long fanout crystal is pumped by a single-mode, narrow-line width continuous-wave 1064 nm fiber laser, which achieves an oscillation threshold of 2 W. For long-term frequency stabilization and control, we actively lock the OPO to an optical transfer cavity (OTC), which is in turn locked to a polarization-stabilized HeNe laser to achieve root-mean-square noise of ≤2.3(2) MHz within 10 ms and absolute OPO idler frequency drifts of <1 MHz/hour. The high output power and narrow line width of the OPO are demonstrated via saturated absorption spectroscopy on the ν3 P(7) transition of CH4 (40−300 mTorr) in a retroreflecting doublepass cell, for which narrow Lamb dips with a full width at half-maximum (fwhm) of 3.1(1) MHz are readily observed. Technical aspects of our monolithic laser block construction, thermal cooling, optical transfer cavity, electronic servo loop control, mirror selection, and beam size considerations for optimal low pumping threshold, long-term frequency stability, and maximal conversion e:ciency are presented, with further details available on request. 

Maxwell relation validated at the single molecule level. The detailed thermodynamics of nucleic acid conformational changes are systematically investigated usingP/T-controlled single molecule FRET experiments. 

A set of modules for the informal learning of quantum science was developed. They include (1) Waves and Bottling Light in Quantum Dots, (2) Quantization of Energy Levels, (3) Particle-Wave Duality, (4) Magnetism and Electron Spin, and (5) Quantum Entanglement. Their teaching objective is to clarify concepts in quantum science, and they have been presented together as part of an hour-long show to ∼250 adults and school-age children. The learning outcomes of the modules were assessed by pre- and postevent quizzes as well as interactive clicker questions. The results suggest effective learning of all of the assessed concepts. These modules are detailed in a way that makes them deployable, together or in part, in other formal or informal settings to support the dissemination of information about quantum science to the general public. 

1D potential along the ring puckering coordinate of cyclobutyl radical represents a double minimum well with a shallow barrier. The equilibrium structure is predicted to be a puckered geometry while the transition state reflects a planar geometry. 

First measurements of internal quantum-state distributions for nitric oxide (NO) evaporating from liquid benzyl alcohol are presented over a broad range of temperatures, performed by liquid-microjet techniques in an essentially collision-free regime, with rotational/spin–orbit populations in the 2 Π 1/2,3/2 manifolds measured by laser-induced fluorescence. The observed rotational distributions exhibit highly linear (i.e., thermal) Boltzmann plots but notably reflect rotational temperatures ( T rot ) as much as 30 K lower than the liquid temperature ( T jet ). A comparable lack of equilibrium behavior is also noted in the electronic degrees of freedom but with populations corresponding to spin–orbit temperatures ( T SO ) consistently higher than T rot by ∼15 K. These results unambiguously demonstrate evaporation into a non-equilibrium distribution, which, by detailed-balance considerations, predict quantum-state-dependent sticking coefficients for incident collisions of NO at the gas–liquid interface. Comparison and parallels with previous experimental studies of NO thermal desorption and molecular-beam scattering in other systems are discussed, which suggests the emergence of a self-consistent picture for the non-equilibrium dynamics.