原子物理
We present a Raman atom interferometer using large momentum transfer without reversing the direction of the effective wavevector ($k$-reversal). More specifically, we use a microwave $\pi$/2 pulse to manipulate the spin state of $^{87}$Rb…
We report a pronounced dependence of magnetic Feshbach resonance spectra on the initial hyperfine-Zeeman state of Li in ultracold $^{138}$Ba$^+$+$^6$Li collisions. The measured number and distribution of resonances differ significantly…
Cold Rydberg atoms, known for their long lifetimes and strong dipole-dipole interactions that lead to the Rydberg blockade phenomenon, are among the most promising platforms for quantum simulations, quantum computation and quantum networks.…
Coronene molecules have been bombarded with protons of energy ranging from 100 to 300 keV. The time of flight mass spectra have been recorded using a two stage Wiley McLaren type spectrometer. A significant enhancement in the yields of…
In this work we study the last two hydrogen molecular ion isotopologues: DT$^+$ and T$_2^+$, for which high-precision calculations have not yet been made. We obtain the nonrelativistic solutions of the Schr\"odinger equation for the wide…
Experimental multi-parameter optimization can enhance the interfacing of cold atoms with waveguides and cavities. Recent implementations of machine learning (ML) algorithms demonstrate the optimization of complex cold atom ex perimental…
The complex Rydberg structure of ytterbium atoms is shaped by multiple low-lying ion-core-excited states and strong channel interactions, which presents both opportunities and challenges for quantum information processing and precision…
We present a temporally-multiplexed dual-colour terahertz (THz) imaging technique using THz-to-optical conversion in atomic vapour. By rapidly alternating the pump laser frequency, we sequentially excite two atomic states, each absorbing a…
We report a single-ion optical atomic clock with fractional frequency uncertainty of $5.5\times10^{-19}$ and fractional frequency stability of $3.5 \times10^{-16}/\sqrt{\tau/\mathrm{s}}$, based on quantum logic spectroscopy of a single…
We investigate the elastic and inelastic scattering of positrons by sodium atoms in both the ground state, Na($3s$), and excited states, Na*($3p$, $4s$, $3d$), using the hyperspherical coordinate method with a model potential to represent…
Energy transfer between different mechanical degrees of freedom in atom-molecule collisions has been widely studied and largely understood. However, systems involving spins remain less explored, especially with a state-to-state precision.…
High-sensitivity laser spectroscopy is integral to applications like atomic clocks, quantum computers, and chemical sensing. Lowering atomic temperature decreases spectral Doppler broadening and increases transit time across the excitation…
Thorium ions and molecules, recognized for their distinctive nuclear and atomic attributes, are central to numerous trapped-ion experiments globally. Our study introduces an effective, compact source of thorium ions produced via laser…
Precision timekeeping is fundamental to modern technologies such as Global Navigation Satellite Systems (GNSS), communication networks, financial transactions, and power grid management. Over the past 50 years, microwave atomic clocks have…
Developing a non-invasive, accurate vector magnetometer that operates at ambient temperature and is conducive to miniaturization and is self-calibrating is a significant challenge. Here, we present an unshielded three-axis vector…
We report the measurement of the ionization energy of the $^{85}\text{Rb}_2$ molecule through resonantly enhanced 2-photon ionization in a supersonic beam. The first photon excites the $X^1\Sigma_g^+ (v_X = 0)\rightarrow B^1\Pi_u (v_B = 2)$…
We present an innovative frequency comb methodology utilizing pulsed lasers for Rydberg atoms and implement it for electric field measurement. It achieves the Rydberg state population of multi-velocity group atoms through the two-photon…
The response of an atom to external electric and magnetic fields can reveal fundamental atomic properties. It has long been verified that, in a static magnetic field, those atomic energy levels with hyperfine interactions shift according to…
Optically active defects suspended in an inert solid are an interesting system for sensing and magnetometry at the nanometer scale, in addition to being a potential source of high-density, identical quantum emitters for quantum information.…
Rydberg atoms, with their giant electric dipole moments and tunable energy-level transitions, offer exceptional potential for microwave (MW) electric field sensing, combining high sensitivity and broad frequency coverage. However,…