[Surgical technique and effectiveness of titanium elastic nail assisted retrograde channel screw implantation in superior pubic branch].

Objective: To investigate the surgical technique and effectiveness of titanium elastic nail (TEN) assisted retrograde channel screw implantation of superior pubic branch.

Methods: The clinical data of 31 patients with pelvic or acetabular fractures treated with retrograde channel screw implantation in superior pubic branch between January 2021 and April 2022 were retrospectively analyzed. Among them, 16 cases were implanted with assistance of TEN (study group) and 15 cases were implanted under the guidance of C-arm X-ray machine (control group).

Radial-mode sensitive probe beam in the rotational Doppler effect.

The rotational Doppler effect (RDE) attracts much attention in various research areas, from acoustics to optics. The observation of RDE mostly depends on the orbital angular momentum of the probe beam, while the impression of radial mode is ambiguous. To clarify the role of radial modes in RDE detection, we reveal the mechanism of interaction between probe beams and rotating objects based on complete Laguerre-Gaussian (LG) modes.

Generation of perfect optical vortex by Laguerre-Gauss beams with a high-order radial index.

Perfect optical vortex (POV) beams have attracted extensive attention because they have the advantage of a radial profile that is independent of orbital angular momentum. To date, it is usually obtained by means of the Fourier transform performed by a lens on Bessel beams. We theoretically and experimentally demonstrate that POV can be generated by performing the Fourier transform on Laguerre-Gauss beams with a high-order radial index.

Remote angular velocity measurement by the cascaded rotational Doppler effect.

The rotational Doppler effect has attracted extensive attention, caused by the angular momentum and energy exchange between rotating objects and waves. However, most previous works used a simple rotation frame, which made use of only a single-round angular momentum and energy exchange. We propose and demonstrate a frame containing a spiral phase plate cascaded with rotating targets to make an amplification of the traditional Doppler shift, and reduce the diffusion of orbital angular momentum modes by half, which means the distance of practical application is doubled theoretically.

Mode sorter designed for (de)multiplexing vector vortex modes.

Mode-division multiplexing is significant in optical communications, and a vector vortex beams (VVBs) set is one of the candidates of the orthogonal set. Although a basic (de)multiplexing scheme has been promoted, there is still a great potential to enable more VVBs with high efficiency. In this work, we promote a vector vortex mode sorter based on a Sagnac interferometer and Q-plate to solve the problem.

Integrated design of pi/2 converter and its experimental performance.

Transverse modes of light have been widely exploited in both classical and quantum optics in recent years. Among the devices to manipulate the transverse modes of light, a π/2 converter is a fundamental and important one that analogs to the quarter-wave plate in the polarization degree of freedom. While a π/2 converter is typically achieved by a pair of well-adjusted cylindrical lenses, it suffers from complexity in its installation and adjustment, which strongly limits its practical applications.