15 research outputs found
Deep Laser Cooling of Thulium Atoms to Sub-K Temperatures in Magneto-Optical Trap
Deep laser cooling of atoms, ions, and molecules facilitates the study of
fundamental physics as well as applied research. In this work, we report on the
narrow-line laser cooling of thulium atoms at the wavelength of
with the natural linewidth of , which
widens the limits of atomic cloud parameters control. Temperatures of about
, phase-space density of up to and
number of trapped atoms were achieved. We have also demonstrated
formation of double cloud structure in an optical lattice by adjusting
parameters of the magneto-optical trap. These results can
be used to improve experiments with BEC, atomic interferometers, and optical
clocks.Comment: 12 pages, 6 figure
Demonstration of a parity-time symmetry breaking phase transition using superconducting and trapped-ion qutrits
Scalable quantum computers hold the promise to solve hard computational
problems, such as prime factorization, combinatorial optimization, simulation
of many-body physics, and quantum chemistry. While being key to understanding
many real-world phenomena, simulation of non-conservative quantum dynamics
presents a challenge for unitary quantum computation. In this work, we focus on
simulating non-unitary parity-time symmetric systems, which exhibit a
distinctive symmetry-breaking phase transition as well as other unique features
that have no counterpart in closed systems. We show that a qutrit, a
three-level quantum system, is capable of realizing this non-equilibrium phase
transition. By using two physical platforms - an array of trapped ions and a
superconducting transmon - and by controlling their three energy levels in a
digital manner, we experimentally simulate the parity-time symmetry-breaking
phase transition. Our results indicate the potential advantage of multi-level
(qudit) processors in simulating physical effects, where additional accessible
levels can play the role of a controlled environment.Comment: 14 pages, 9 figure
Antihydrogen and Hydrogen: Search for the Difference
Our universe consists mainly of regular matter, while the amount of antimatter seems to be negligible. The origin of this difference, known as the baryon asymmetry, remains undiscovered. Since the discovery of antimatter, many experiments have been carried out to study antiparticles and to compare matter and antimatter twins. Two of the most sensitive methods in physics, radiofrequency and optical spectroscopy, can be efficiently used to search for the difference. The successful synthesis and trapping of cold antihydrogen atoms opened the possibility of significantly increasing the sensitivity of matter/antimatter tests. This brief review focuses on a hydrogen/antihydrogen comparison using other independent spectroscopic measurements of single particles in traps and other simple atomic systems like positronium. Although no significant difference is detected in today’s level of accuracy, one can push forward the sensitivity by improving the accuracy of 1S–2S positronium spectroscopy, spectroscopy of hyperfine transition in antihydrogen, and gravitational measurements
Laser systems stabilized to cryogenic silicon cavities for precision measurements
We consider laser systems stabilized to external Fabry-Perot silicon cavities operated at cryogenic temperatures. In order to characterize frequency stability two identical systems were created. Fractional frequency instability of individual system reached 6×10-15 at 1 s. Different sources of noises were studied, and the dominant one now is the fluctuations of residual amplitude modulation
Laser systems stabilized to cryogenic silicon cavities for precision measurements
We consider laser systems stabilized to external Fabry-Perot silicon cavities operated at cryogenic temperatures. In order to characterize frequency stability two identical systems were created. Fractional frequency instability of individual system reached 6×10-15 at 1 s. Different sources of noises were studied, and the dominant one now is the fluctuations of residual amplitude modulation
Toward a New Generation of Compact Transportable Yb<sup>+</sup> Optical Clocks
Optical atomic clocks are currently one of the most sensitive tools making it possible to precisely test the fundamental symmetry properties of spacetime and Einstein’s theory of relativity. At the same time, the extremely high stability and accuracy of compact transportable optical clocks open new perspectives in important fields, such as satellite navigation, relativistic geodesy, and the global time and frequency network. Our project aimed to develop a compact transportable optical clock based on a single ytterbium ion. We present the first prototype of the Yb+ clock (298 kg in 1 m3) and present several solutions aimed to improve the clock’s robustness to approach the demands of a space-qualified system. We present spectroscopic studies of a 435.5 nm quadrupole clock transition with Fourier-limited spectra of 25 Hz. The estimated instability of the output frequency at 1 GHz, which was down-converted with an optical frequency comb (OFC), is at the level of 9×10−15/τ, and the long-term instability and inaccuracy are at the level of 5×10−16. As the next steps, we present a new design for the clock laser and the OFC
Toward a New Generation of Compact Transportable Yb+ Optical Clocks
Optical atomic clocks are currently one of the most sensitive tools making it possible to precisely test the fundamental symmetry properties of spacetime and Einstein’s theory of relativity. At the same time, the extremely high stability and accuracy of compact transportable optical clocks open new perspectives in important fields, such as satellite navigation, relativistic geodesy, and the global time and frequency network. Our project aimed to develop a compact transportable optical clock based on a single ytterbium ion. We present the first prototype of the Yb+ clock (298 kg in 1 m3) and present several solutions aimed to improve the clock’s robustness to approach the demands of a space-qualified system. We present spectroscopic studies of a 435.5 nm quadrupole clock transition with Fourier-limited spectra of 25 Hz. The estimated instability of the output frequency at 1 GHz, which was down-converted with an optical frequency comb (OFC), is at the level of 9×10−15/τ, and the long-term instability and inaccuracy are at the level of 5×10−16. As the next steps, we present a new design for the clock laser and the OFC