Related papers: Precise Determination of Minimum Achievable Temper…
We report the complete characterization of various cooling grade Tm-doped crystals including the first demonstration of optical refrigeration in Tm:YLF crystals. Room temperature laser cooling efficiencies of 1% and 2% (mol) Tm:YLF, and 1%…
We report the first demonstration of solid-state optical refrigeration of a Ho-doped material. A 1 mol% Ho-doped Yttrium Lithium Fluoride (YLF) crystal is cooled by mid-IR laser radiation, and its external quantum efficiency and parasitic…
We report laser cooling of Yb3+-doped KY3F10 (Yb:KY3F10) driven by a 100-W, 1020-nm pump source. Despite pumping at a non-optimal wavelength, high-quality KY3F10 crystals doped with 3% and 7% Yb were cooled to 145 K and 151 K, respectively,…
Laser cooling of a solid is achieved when a coherent laser illuminates the material, and the heat is extracted by resulting anti-Stokes fluorescence. Over the past year, net solid-state laser cooling was successfully demonstrated for the…
We have argued that a high-purity Yb-doped silica glass can potentially be cooled via anti-Stokes fluorescence optical refrigeration. This conclusion is reached by showing, using reasonable assumptions for the host material properties, that…
We investigate the improvement of anti-Stokes laser cooling of a Yb$^{3+}$:YLF nanocrystal in a Fabry-P\'erot microcavity via the Purcell effect. Our analysis accounts for both the enhancement of emission lines resonant with the cavity…
YbF has been identified as a molecule that can be used to investigate charge-parity symmetry violations that are beyond the Standard Model of particle physics. Cooling to sub-milli-Kelvin is advantageous for experiments that probe…
Since the first demonstration of optical refrigeration in a rare-earth-doped glass nearly 30 years ago, the nascent field of laser cooling solids has progressed significantly. It is now possible to demonstrate payload cooling to ~91 K using…
Advances in cryogenic sciences have enabled several observations of new low-temperature physical phenomena including superconductivity, superfluidity, and Bose-Einstein condensates. Heat transfer is also critical in numerous applications…
We explore spin dynamics of isotopically purified $^{166}$Er:$^{7}$LiYF$_4$ crystal below 1 Kelvin and at weak magnetic fields $<$0.3 T. Crystals grown in our lab demonstrate record-narrow inhomogeneous optical broadening down to 16~MHz.…
The ability to cool and manipulate levitated nano-particles in vacuum is a promising new tool for exploring macroscopic quantum mechanics\cite{WanPRL2016,Scala2013,Zhang2013}, precision measurements of forces, \cite{GambhirPRA2016} and…
We use two-dimensional transverse laser cooling to produce an ultracold beam of YbF molecules. Through experiments and numerical simulations, we study how the cooling is influenced by the polarization configuration, laser intensity, laser…
In addition to being suitable for laser cooling and trapping in a magneto-optical trap (MOT) using a relatively broad ($\sim$5 MHz) transition, the molecule YO possesses a narrow-line transition. This forbidden transition between the…
The development of reliable luminescent nanothermometers for cryogenic applications is essential for advancing quantum technologies, superconducting systems, and other fields that require precise, high-spatial-resolution temperature…
A novel, to the best of our knowledge, ultralow-temperature luminescence thermometry strategy is proposed, based on a measurement of relative intensities of hyperfine components in the spectra of Ho$^{3+}$ ions doped into a crystal. A…
A ytterbium doped silica optical fiber has been cooled by 18.4K below ambient temperature by pumping with 20W of 1035nm light in vacuum. In air, cooling by 3.6K below ambient was observed with the same 20W pump. The temperatures were…
We report on the sub-Doppler laser cooling of neutral $^{171}$Yb and $^{173}$Yb in a magneto-optical trap using the $^{1}S_{0}$-$^{1}P_{1}$ transition at 398.9nm. We use two independent means to estimate the temperature of the atomic cloud…
Optical refrigeration of solids with anti-Stokes fluorescence has been widely explored as a vibration-free cryogenic cooling technology. A minimum temperature of 87 K has been demonstrated with rare-earth ion doped crystals using optical…
The established approach to laser cooling of solids relies on anti-Stokes fluorescence, for example from rare earth impurities in glass. Although successful, there is a minimum temperature to which such a process can cool set by the…
We demonstrate launching of laser-cooled Yb atoms in a cold atomic fountain. Atoms in a collimated thermal beam are first cooled and captured in a magneto-optic trap (MOT) operating on the strongly-allowed ${^1S}_0 \rightarrow {^1P}_1$…