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Accurate, high spatial resolution thermal measurements have provided fundamental insights into many fields of study; however, existing thermometer technology often suffers from one or more limitati...

Recently, the thulium atom was cooled down to the Bose-Einstein condensation temperature, thus opening a pathway to quantum simulation with this atom. However, successful simulations require instruments to control and readout states of the atom as well as the ability to control the interaction between either different species or different states of the same type of species. In this paper, we provide an experimental demonstration of high-fidelity (over 93%) manipulation of the ground state magnetic sublevels of thulium, which utilizes a simple and efficient design of a microwave (MW) antenna. The coherence time and dephasing rate of the energetically highest hyperfine level of the ground state were also examined.

We present high-resolution, all-optical thermometry based on ensembles of germanium-vacancy (GeV) color center in diamond and implement this method of thermometry in the fiber-optic format. Due to the unique properties of diamond, an all-optical approach using this method opens a way to produce back-action-free temperature measurements with resolution below 0.1 K in a wide range of temperatures.

We present the design, fabrication and characterization of high quality factor silicon nitride nanobeam PhC cavities at visible wavelengths for coupling to diamond color centers in a cavity QED system. We demonstrate devices with a quality factor of ∼24, 000 (±250) around the zero-phonon line of the germanium-vacancy center in diamond. We also present an efficient fiber-to-waveguide coupling platform for suspended nanophotonics. By gently changing the corresponding effective indices at the fiber-waveguide interface, we achieve a coupling efficiency of ∼96% (±2%) at the cavity resonance.

Here, we report on the observation of a random to chaotic temperature transformation in the statistics of nearest-neighbor spacings of Fano-Feshbach resonances in the ultracold polarized gas of thulium-169 atoms. We associate this transformation to the appearance of so-called $d$ resonances as well as the shift of other resonances with the temperature. In addition to this statistical change, it has been observed that the characters of $s$- and $d$-resonance temperature shifts are quite different: $s$ resonances experience almost no shift or even negative shift with the temperature, while $d$ resonances experience an obvious positive shift. The sign change was attributed to the difference in polarizability of Feshbach molecules and free thulium atoms. In addition, careful analysis of the broad Fano-Feshbach resonances enabled the determination of the sign of thulium's background scattering length. A rethermalization experiment made it possible to estimate a length value of ${a}_{\mathrm{bg}}=+144\ifmmode\pm\else\textpm\fi{}38\text{ }\text{ }\mathrm{a}.\mathrm{u}.$ This indicates that thulium atoms are suitable for achieving Bose-Einstein condensation.

The nitrogen-vacancy (NV) center in diamond has been found to be a powerful tool for various sensing applications. In particular, in ensemble-based sensors, the main ``workhorse'' so far has been optically detected electron resonance. Utilization of the nuclear spin has the potential to significantly improve sensitivity in rotation and magnetic field sensors. Ensemble-based sensors consume a substantial amount of power, leading to noticeable heating of the diamond and thus requiring an understanding of temperature-related shifts. In this paper, we provide a detailed study of the temperature shift of the hyperfine components of the NV center.

Minimization of internal degrees of freedom is an important step in the cooling of atomic species to degeneracy temperature. Here, we report on the loading of 6*10^5 thulium atoms optically polarized at maximum possible magnetic quantum number mf=-4 state into dipole trap operating at 532 nm. The purity of polarizations of the atoms was experimentally verified using a Stern-Gerlach-type experiment. Experimental measured polarization of the state is 3.91(26).

A design for an ultrahigh Q/V nanobeam cavity engineered to interact with Germanium-vacancy (GeV) centers is presented. The nanobeam cavity supports a mode with Q/V>108 with transmission over 70%. The proposed design is based on a new scalable approach developed to reduce the footprint of nanobeam cavities by more than 50% without losing the cavity Q/V value and transmission. Cavity quantum electrodynamics analysis reveals that strong coupling between the zero-phonon line transition of GeV centers and the cavity mode can be achieved for a range of nanobeam dimensions.

Laser cooling and trapping became powerful tool enabling number of research activities and applications such as quantum simulation [1], quantum information processing [2], control of light propagation and switching of optical pulses [3] including single photon gates [4], metrology and testing drift of fundamental constants [5]. Recently rare earth elements attracted considerable attention due to the high orbital and magnetic moments. Such a systems allow low-field Feshabach resonances [6] enabling tunable in wide range interactions, relatively large dipole-dipole interactions. In particular, thulium atom has one hole in 4f shell therefore having orbital moment of 3 in the ground state, magnetic moment of 4 Bohr magnetons in ground state. While magnetic moment of the thulium atom is less than that of Erbium or Dysprosium [7, 8] simpler level structure, possibility to capture thulium atoms and the dipole trap at 532nm [9] make thulium atom an extremely attractive subject for quantum simulations and quantum information processing. In this contribution, I will present our efforts toward brining thulium atom to ultracold temperatures and quantum degeneracy as well as our study of collisional proprieties of thulium atom.

Color centers in diamonds have shown promising potential for luminescent thermometry. So far, the nitrogen-vacancy (NV) color center has demonstrated a high sensitivity for optical temperature monitoring in biological systems. However, the NV center requires microwave excitation which can cause unwanted heating, and the NV is also sensitive to non-axial magnetic fields, both of which can result in inaccurate temperature measurements. To overcome this drawback, the silicon-vacancy (SiV) and germanium-vacancy (GeV) color centers in diamonds have recently been explored and have shown good optical temperature sensitivity owing to the temperature dependent wavelength optical zero-phonon line. Here, we report optical temperature measurements using the recently discovered tin-vacancy (SnV) color center in diamond and show sensitivity better than 0.2 K in 10 s integration time. Also, we compare the relative merits of SnV with respect to SiV and GeV for luminescent thermometry. These results illustrate that there are likely to be many future options for nanoscale thermometry using diamonds.

We studied light-assisted collisions of Tm atoms in a magneto-optical trap (MOT), working on a weak cooling transition at 530.7 nm [$4{f}^{13}(^{2}F^{o})6{s}^{2},\phantom{\rule{0.16em}{0ex}}J=7/2,\phantom{\rule{0.16em}{0ex}}F=4$ to $4{f}^{12}(^{3}H_{6})5{d}_{5/2}6{s}^{2},\phantom{\rule{0.16em}{0ex}}J=9/2,\phantom{\rule{0.16em}{0ex}}F=5$]. We observed a strong influence from radiation trapping and light-assisted collisions on the dynamics of this trap. We carefully separated these two contributions and measured the binary loss rate constant at different laser powers and detuning frequencies near the cooling transition. Analyzing losses from the MOT, we found the light-assisted inelastic binary loss rate constant to reach values of up to $\ensuremath{\beta}={10}^{\ensuremath{-}9}\phantom{\rule{0.16em}{0ex}}\mathrm{c}{\mathrm{m}}^{3}/\mathrm{s}$ and gave the upper bound on a branching ratio $kl0.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ for the 530.7 nm transition.