arXiv subjects

Guangren Sun

Publications and source records attributed to Guangren Sun.

3 recordsLinked to original sources

arXiv2026

A compact setup for 87Rb optical tweezer arrays

We describe a simple and compact experimental setup for optical tweezer arrays of 87Rb atoms. This setup includes a compact vacuum system, a single cooling laser, a simple tweezer laser, and a flexible control system. The small vacuum system with only 40 cm length takes advantage of the high atomic flux two-dimensional magneto-optical trap (2D MOT) while maintaining a low background pressure in the 3D MOT chamber ensuring sufficient lifetime of the trapped atoms. Atom number of the laser cooled sample of 2e7 and temperature of 92 uK is achieved. The flexible control system with real-time waveform generator modules (RWG) provides precise control of all the RF devices, and enables real-time feedback control of both the global and individual beams in optical tweezer arrays. An optical tweezer array with 25x25 homogeneous traps is demonstrated. This simple and compact demo setup makes it more accessible to experimental quantum physics.

cond-mat.quant-gas↗

arXiv2025

A stable phase-locking-free single beam optical lattice with multiple configurations

Optical lattices formed by interfering laser beams are widely used to trap and manipulate atoms for quantum simulation, metrology, and computation. To stabilize optical lattices in experiments, it is usually challenging to implement delicate phase-locking systems with complicated optics and electronics to reduce the relative phase fluctuation of multiple laser beams. Here we report a phase-locking-free scheme to implement optical lattices by passing a single laser beam through a prism with n-fold symmetric facets and large apex angles. The scheme ensures a stable optical lattice since the interference occurs among different deflected parts of a single laser beam without any moving component. Various lattice configurations, including a triangular lattice and a quasi-crystal lattice with ten-fold symmetry are demonstrated. In both cases, stability measurements show a change of lattice constant in less than 1.14%, and a drift of lattice position in less than 1.61%.

quant-ph↗

arXiv2024

An efficient method to generate near-ideal hollow beams of different shapes for box potential of quantum gases

Ultracold quantum gases are usually prepared in conservative traps for quantum simulation experiments. The atomic density inhomogeneity, together with the consequent position-dependent energy and time scales of cold atoms in traditional harmonic traps, makes it difficult to manipulate and detect the sample at a better level. These problems are partially solved by optical box traps of blue-detuned hollow beams. However, generating a high-quality hollow beam with high light efficiency for the box trap is challenging. Here, we present a scheme that combines the fixed optics, including axicons and prisms, to pre-shape a Gaussian beam into a hollow beam, with a digital micromirror device (DMD) to improve the quality of the hollow beam further, providing a nearly ideal optical potential of various shapes for preparing highly homogeneous cold atoms. The highest power-law exponent of potential walls can reach a value over 100, and the light efficiency from a Gaussian to a hollow beam is also improved compared to direct optical shaping by a mask or a DMD. Combined with a one-dimensional optical lattice, a nearly ideal two-dimensional uniform quantum gas with different geometrical boundaries can be prepared for exploring quantum many-body physics to an unprecedented level.

cond-mat.quant-gas↗