原子物理
We present new results on the ionization by electron impacts in a dense plasma. We are interested in the density effect known as the ionization potential depression and in its role in atomic structure. Rather than using the well-known…
Gauge theory requires physical observables to be gauge-independent. However, ever since Lamb noticed the problem of gauge selection in calculating atomic spontaneous radiation spectrum, the problem of gauge dependence was encountered in…
High precision mass and $g$-factor measurements in Penning traps have enabled groundbreaking tests of fundamental physics. The most advanced setups use multi-trap methods, which employ transport of particles between specialized trap zones.…
We investigate a possible realization of an ultracold-atom rotation sensor that is based on recently proposed tractor atom interferometry (TAI). An experimental design that includes generation of a Laguerre-Gaussian-beam-based "pinwheel"…
We investigate 13 hyperfine structures of transition lines of 127I2 near 554 nm, namely, the R(50) 22-0, P(46) 22-0, P(121) 24-0, P(69) 25-1, R(146) 25-0, R(147) 28-1, P(160) 26-0, P(102) 26-1, R(96) 23-0, R(49) 22-0, P(45) 22-0, P(92)…
The momentum of light in a medium and the mechanisms of momentum transfer between light and dielectrics have long been the topic of controversies and confusion. We discuss here the problem of momentum transfers that follow the refraction of…
We report precise measurement of the hyperfine splitting and calculation of the Zeeman coefficients of the $^{171}$Yb$^+$ ground state. The absolute hyperfine splitting frequency is measured using high-resolution laser-microwave…
Atomic hydrogen energy levels calculated to high precision are required to assist experimental researchers working on spectroscopy in the pursuit of testing quantum electrodynamics (QED) and probing for physics beyond the Standard Model.…
We report a measurement of the hyperfine-structure constants of the $^{85}$Rb 4$D_{3/2}$ state using a two-photon 5$S_{1/2}\rightarrow$4$D_{3/2}$ transition. The hyperfine transitions are probed by measuring the transmission of the…
Highly charged ions (HCIs) have drawn significant interest in quantum metrology and in search for new physics. Among these, Ni12+ is considered as one of the most promising candidates for the next generation of HCI optical clocks, due to…
It has been well established that the Jastrow correlation factor can effectively capture the electron correlation effects, and thus, the efficient optimization of the many-body wave function including the Jastrow correlation factor is of…
We demonstrate the Doppler laser cooling of $^{40}$Ca$^+$ ions confined in a segmented linear Paul trap in the presence of a strong quadrupolar magnetic field generated by two permanent ring magnets. Magnetic field gradients of 800 to 1600…
We report the engineering of molecular potentials at large interatomic distances. The molecular states are generated by off-resonant optical coupling to a highly excited, long-range Rydberg molecular potential. The coupling produces a…
We present an all-optical method for efficiently preparing cold atoms in a desired Zeeman state, either on the magnetically insensitive clock state (m_F=0) or a particular state suitable for processing or storing quantum information. By…
This work examines optimized strategies for the preparation of single molecular ions in well-defined rotational quantum states in an ion trap with the example of the molecular nitrogen ion N2+. It advances a two-step approach consisting of…
Optically active defects in solid-state systems have many applications in quantum information and sensing. However, unlike free atoms, which have fixed optical transition frequencies, the inhomogeneous broadening of the transitions in…
This paper introduces a method for characterizing the current noise of commercial constant-current sources(CCSs) using a free-induction-decay(FID) type optically-pumped rubidium atomic magnetometer driven by a radio-frequency(RF) magnetic…
We present a simple and general coherence model for multiorbital tunnel ionization of molecules, which we incorporate into our previously developed density matrix approach for sequential double ionization [Yuen and Lin, Phys. Rev. A 106,…
Optical atomic clocks are the most accurate measurement devices ever constructed and have found many applications in fundamental science and technology. The use of highly charged ions (HCI) as a new class of references for highest accuracy…
The calculation of the parity-violating polarizations in the external electric field, which are associated with the electron electric dipole moment ($e$EDM) and magnetic quadrupole moment (MQM) of the $^{175}$Lu nucleus, as well as the…